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v6.8
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  Security-Enhanced Linux (SELinux) security module
   4 *
   5 *  This file contains the SELinux hook function implementations.
   6 *
   7 *  Authors:  Stephen Smalley, <stephen.smalley.work@gmail.com>
   8 *	      Chris Vance, <cvance@nai.com>
   9 *	      Wayne Salamon, <wsalamon@nai.com>
  10 *	      James Morris <jmorris@redhat.com>
  11 *
  12 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  13 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  14 *					   Eric Paris <eparis@redhat.com>
  15 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  16 *			    <dgoeddel@trustedcs.com>
  17 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  18 *	Paul Moore <paul@paul-moore.com>
  19 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  20 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
  21 *  Copyright (C) 2016 Mellanox Technologies
  22 */
  23
  24#include <linux/init.h>
  25#include <linux/kd.h>
  26#include <linux/kernel.h>
  27#include <linux/kernel_read_file.h>
  28#include <linux/errno.h>
  29#include <linux/sched/signal.h>
  30#include <linux/sched/task.h>
  31#include <linux/lsm_hooks.h>
  32#include <linux/xattr.h>
  33#include <linux/capability.h>
  34#include <linux/unistd.h>
  35#include <linux/mm.h>
  36#include <linux/mman.h>
  37#include <linux/slab.h>
  38#include <linux/pagemap.h>
  39#include <linux/proc_fs.h>
  40#include <linux/swap.h>
  41#include <linux/spinlock.h>
  42#include <linux/syscalls.h>
  43#include <linux/dcache.h>
  44#include <linux/file.h>
  45#include <linux/fdtable.h>
  46#include <linux/namei.h>
  47#include <linux/mount.h>
  48#include <linux/fs_context.h>
  49#include <linux/fs_parser.h>
  50#include <linux/netfilter_ipv4.h>
  51#include <linux/netfilter_ipv6.h>
  52#include <linux/tty.h>
  53#include <net/icmp.h>
  54#include <net/ip.h>		/* for local_port_range[] */
  55#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
  56#include <net/inet_connection_sock.h>
  57#include <net/net_namespace.h>
  58#include <net/netlabel.h>
  59#include <linux/uaccess.h>
  60#include <asm/ioctls.h>
  61#include <linux/atomic.h>
  62#include <linux/bitops.h>
  63#include <linux/interrupt.h>
  64#include <linux/netdevice.h>	/* for network interface checks */
  65#include <net/netlink.h>
  66#include <linux/tcp.h>
  67#include <linux/udp.h>
  68#include <linux/dccp.h>
  69#include <linux/sctp.h>
  70#include <net/sctp/structs.h>
  71#include <linux/quota.h>
  72#include <linux/un.h>		/* for Unix socket types */
  73#include <net/af_unix.h>	/* for Unix socket types */
  74#include <linux/parser.h>
  75#include <linux/nfs_mount.h>
  76#include <net/ipv6.h>
  77#include <linux/hugetlb.h>
  78#include <linux/personality.h>
  79#include <linux/audit.h>
  80#include <linux/string.h>
  81#include <linux/mutex.h>
  82#include <linux/posix-timers.h>
  83#include <linux/syslog.h>
  84#include <linux/user_namespace.h>
  85#include <linux/export.h>
  86#include <linux/msg.h>
  87#include <linux/shm.h>
  88#include <uapi/linux/shm.h>
  89#include <linux/bpf.h>
  90#include <linux/kernfs.h>
  91#include <linux/stringhash.h>	/* for hashlen_string() */
  92#include <uapi/linux/mount.h>
  93#include <linux/fsnotify.h>
  94#include <linux/fanotify.h>
  95#include <linux/io_uring/cmd.h>
  96#include <uapi/linux/lsm.h>
  97
  98#include "avc.h"
  99#include "objsec.h"
 100#include "netif.h"
 101#include "netnode.h"
 102#include "netport.h"
 103#include "ibpkey.h"
 104#include "xfrm.h"
 105#include "netlabel.h"
 106#include "audit.h"
 107#include "avc_ss.h"
 108
 109#define SELINUX_INODE_INIT_XATTRS 1
 110
 111struct selinux_state selinux_state;
 112
 113/* SECMARK reference count */
 114static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 115
 116#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 117static int selinux_enforcing_boot __initdata;
 118
 119static int __init enforcing_setup(char *str)
 120{
 121	unsigned long enforcing;
 122	if (!kstrtoul(str, 0, &enforcing))
 123		selinux_enforcing_boot = enforcing ? 1 : 0;
 124	return 1;
 125}
 126__setup("enforcing=", enforcing_setup);
 127#else
 128#define selinux_enforcing_boot 1
 129#endif
 130
 131int selinux_enabled_boot __initdata = 1;
 132#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 133static int __init selinux_enabled_setup(char *str)
 134{
 135	unsigned long enabled;
 136	if (!kstrtoul(str, 0, &enabled))
 137		selinux_enabled_boot = enabled ? 1 : 0;
 138	return 1;
 139}
 140__setup("selinux=", selinux_enabled_setup);
 141#endif
 142
 
 
 
 143static int __init checkreqprot_setup(char *str)
 144{
 145	unsigned long checkreqprot;
 146
 147	if (!kstrtoul(str, 0, &checkreqprot)) {
 
 148		if (checkreqprot)
 149			pr_err("SELinux: checkreqprot set to 1 via kernel parameter.  This is no longer supported.\n");
 150	}
 151	return 1;
 152}
 153__setup("checkreqprot=", checkreqprot_setup);
 154
 155/**
 156 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 157 *
 158 * Description:
 159 * This function checks the SECMARK reference counter to see if any SECMARK
 160 * targets are currently configured, if the reference counter is greater than
 161 * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 162 * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 163 * policy capability is enabled, SECMARK is always considered enabled.
 164 *
 165 */
 166static int selinux_secmark_enabled(void)
 167{
 168	return (selinux_policycap_alwaysnetwork() ||
 169		atomic_read(&selinux_secmark_refcount));
 170}
 171
 172/**
 173 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 174 *
 175 * Description:
 176 * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 177 * (1) if any are enabled or false (0) if neither are enabled.  If the
 178 * always_check_network policy capability is enabled, peer labeling
 179 * is always considered enabled.
 180 *
 181 */
 182static int selinux_peerlbl_enabled(void)
 183{
 184	return (selinux_policycap_alwaysnetwork() ||
 185		netlbl_enabled() || selinux_xfrm_enabled());
 186}
 187
 188static int selinux_netcache_avc_callback(u32 event)
 189{
 190	if (event == AVC_CALLBACK_RESET) {
 191		sel_netif_flush();
 192		sel_netnode_flush();
 193		sel_netport_flush();
 194		synchronize_net();
 195	}
 196	return 0;
 197}
 198
 199static int selinux_lsm_notifier_avc_callback(u32 event)
 200{
 201	if (event == AVC_CALLBACK_RESET) {
 202		sel_ib_pkey_flush();
 203		call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 204	}
 205
 206	return 0;
 207}
 208
 209/*
 210 * initialise the security for the init task
 211 */
 212static void cred_init_security(void)
 213{
 
 214	struct task_security_struct *tsec;
 215
 216	tsec = selinux_cred(unrcu_pointer(current->real_cred));
 217	tsec->osid = tsec->sid = SECINITSID_KERNEL;
 218}
 219
 220/*
 221 * get the security ID of a set of credentials
 222 */
 223static inline u32 cred_sid(const struct cred *cred)
 224{
 225	const struct task_security_struct *tsec;
 226
 227	tsec = selinux_cred(cred);
 228	return tsec->sid;
 229}
 230
 231static void __ad_net_init(struct common_audit_data *ad,
 232			  struct lsm_network_audit *net,
 233			  int ifindex, struct sock *sk, u16 family)
 234{
 235	ad->type = LSM_AUDIT_DATA_NET;
 236	ad->u.net = net;
 237	net->netif = ifindex;
 238	net->sk = sk;
 239	net->family = family;
 240}
 241
 242static void ad_net_init_from_sk(struct common_audit_data *ad,
 243				struct lsm_network_audit *net,
 244				struct sock *sk)
 245{
 246	__ad_net_init(ad, net, 0, sk, 0);
 247}
 248
 249static void ad_net_init_from_iif(struct common_audit_data *ad,
 250				 struct lsm_network_audit *net,
 251				 int ifindex, u16 family)
 252{
 253	__ad_net_init(ad, net, ifindex, NULL, family);
 254}
 255
 256/*
 257 * get the objective security ID of a task
 258 */
 259static inline u32 task_sid_obj(const struct task_struct *task)
 260{
 261	u32 sid;
 262
 263	rcu_read_lock();
 264	sid = cred_sid(__task_cred(task));
 265	rcu_read_unlock();
 266	return sid;
 267}
 268
 269static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 270
 271/*
 272 * Try reloading inode security labels that have been marked as invalid.  The
 273 * @may_sleep parameter indicates when sleeping and thus reloading labels is
 274 * allowed; when set to false, returns -ECHILD when the label is
 275 * invalid.  The @dentry parameter should be set to a dentry of the inode.
 276 */
 277static int __inode_security_revalidate(struct inode *inode,
 278				       struct dentry *dentry,
 279				       bool may_sleep)
 280{
 281	struct inode_security_struct *isec = selinux_inode(inode);
 282
 283	might_sleep_if(may_sleep);
 284
 285	if (selinux_initialized() &&
 286	    isec->initialized != LABEL_INITIALIZED) {
 287		if (!may_sleep)
 288			return -ECHILD;
 289
 290		/*
 291		 * Try reloading the inode security label.  This will fail if
 292		 * @opt_dentry is NULL and no dentry for this inode can be
 293		 * found; in that case, continue using the old label.
 294		 */
 295		inode_doinit_with_dentry(inode, dentry);
 296	}
 297	return 0;
 298}
 299
 300static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 301{
 302	return selinux_inode(inode);
 303}
 304
 305static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 306{
 307	int error;
 308
 309	error = __inode_security_revalidate(inode, NULL, !rcu);
 310	if (error)
 311		return ERR_PTR(error);
 312	return selinux_inode(inode);
 313}
 314
 315/*
 316 * Get the security label of an inode.
 317 */
 318static struct inode_security_struct *inode_security(struct inode *inode)
 319{
 320	__inode_security_revalidate(inode, NULL, true);
 321	return selinux_inode(inode);
 322}
 323
 324static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 325{
 326	struct inode *inode = d_backing_inode(dentry);
 327
 328	return selinux_inode(inode);
 329}
 330
 331/*
 332 * Get the security label of a dentry's backing inode.
 333 */
 334static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 335{
 336	struct inode *inode = d_backing_inode(dentry);
 337
 338	__inode_security_revalidate(inode, dentry, true);
 339	return selinux_inode(inode);
 340}
 341
 342static void inode_free_security(struct inode *inode)
 343{
 344	struct inode_security_struct *isec = selinux_inode(inode);
 345	struct superblock_security_struct *sbsec;
 346
 347	if (!isec)
 348		return;
 349	sbsec = selinux_superblock(inode->i_sb);
 350	/*
 351	 * As not all inode security structures are in a list, we check for
 352	 * empty list outside of the lock to make sure that we won't waste
 353	 * time taking a lock doing nothing.
 354	 *
 355	 * The list_del_init() function can be safely called more than once.
 356	 * It should not be possible for this function to be called with
 357	 * concurrent list_add(), but for better safety against future changes
 358	 * in the code, we use list_empty_careful() here.
 359	 */
 360	if (!list_empty_careful(&isec->list)) {
 361		spin_lock(&sbsec->isec_lock);
 362		list_del_init(&isec->list);
 363		spin_unlock(&sbsec->isec_lock);
 364	}
 365}
 366
 
 
 
 
 
 
 
 367struct selinux_mnt_opts {
 368	u32 fscontext_sid;
 369	u32 context_sid;
 370	u32 rootcontext_sid;
 371	u32 defcontext_sid;
 372};
 373
 374static void selinux_free_mnt_opts(void *mnt_opts)
 375{
 376	kfree(mnt_opts);
 
 
 
 
 
 377}
 378
 379enum {
 380	Opt_error = -1,
 381	Opt_context = 0,
 382	Opt_defcontext = 1,
 383	Opt_fscontext = 2,
 384	Opt_rootcontext = 3,
 385	Opt_seclabel = 4,
 386};
 387
 388#define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
 389static const struct {
 390	const char *name;
 391	int len;
 392	int opt;
 393	bool has_arg;
 394} tokens[] = {
 395	A(context, true),
 396	A(fscontext, true),
 397	A(defcontext, true),
 398	A(rootcontext, true),
 399	A(seclabel, false),
 400};
 401#undef A
 402
 403static int match_opt_prefix(char *s, int l, char **arg)
 404{
 405	int i;
 406
 407	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
 408		size_t len = tokens[i].len;
 409		if (len > l || memcmp(s, tokens[i].name, len))
 410			continue;
 411		if (tokens[i].has_arg) {
 412			if (len == l || s[len] != '=')
 413				continue;
 414			*arg = s + len + 1;
 415		} else if (len != l)
 416			continue;
 417		return tokens[i].opt;
 418	}
 419	return Opt_error;
 420}
 421
 422#define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 423
 424static int may_context_mount_sb_relabel(u32 sid,
 425			struct superblock_security_struct *sbsec,
 426			const struct cred *cred)
 427{
 428	const struct task_security_struct *tsec = selinux_cred(cred);
 429	int rc;
 430
 431	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 
 432			  FILESYSTEM__RELABELFROM, NULL);
 433	if (rc)
 434		return rc;
 435
 436	rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 
 437			  FILESYSTEM__RELABELTO, NULL);
 438	return rc;
 439}
 440
 441static int may_context_mount_inode_relabel(u32 sid,
 442			struct superblock_security_struct *sbsec,
 443			const struct cred *cred)
 444{
 445	const struct task_security_struct *tsec = selinux_cred(cred);
 446	int rc;
 447	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 
 448			  FILESYSTEM__RELABELFROM, NULL);
 449	if (rc)
 450		return rc;
 451
 452	rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 
 453			  FILESYSTEM__ASSOCIATE, NULL);
 454	return rc;
 455}
 456
 457static int selinux_is_genfs_special_handling(struct super_block *sb)
 458{
 459	/* Special handling. Genfs but also in-core setxattr handler */
 460	return	!strcmp(sb->s_type->name, "sysfs") ||
 461		!strcmp(sb->s_type->name, "pstore") ||
 462		!strcmp(sb->s_type->name, "debugfs") ||
 463		!strcmp(sb->s_type->name, "tracefs") ||
 464		!strcmp(sb->s_type->name, "rootfs") ||
 465		(selinux_policycap_cgroupseclabel() &&
 466		 (!strcmp(sb->s_type->name, "cgroup") ||
 467		  !strcmp(sb->s_type->name, "cgroup2")));
 468}
 469
 470static int selinux_is_sblabel_mnt(struct super_block *sb)
 471{
 472	struct superblock_security_struct *sbsec = selinux_superblock(sb);
 473
 474	/*
 475	 * IMPORTANT: Double-check logic in this function when adding a new
 476	 * SECURITY_FS_USE_* definition!
 477	 */
 478	BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
 479
 480	switch (sbsec->behavior) {
 481	case SECURITY_FS_USE_XATTR:
 482	case SECURITY_FS_USE_TRANS:
 483	case SECURITY_FS_USE_TASK:
 484	case SECURITY_FS_USE_NATIVE:
 485		return 1;
 486
 487	case SECURITY_FS_USE_GENFS:
 488		return selinux_is_genfs_special_handling(sb);
 489
 490	/* Never allow relabeling on context mounts */
 491	case SECURITY_FS_USE_MNTPOINT:
 492	case SECURITY_FS_USE_NONE:
 493	default:
 494		return 0;
 495	}
 496}
 497
 498static int sb_check_xattr_support(struct super_block *sb)
 499{
 500	struct superblock_security_struct *sbsec = selinux_superblock(sb);
 501	struct dentry *root = sb->s_root;
 502	struct inode *root_inode = d_backing_inode(root);
 503	u32 sid;
 504	int rc;
 505
 506	/*
 507	 * Make sure that the xattr handler exists and that no
 508	 * error other than -ENODATA is returned by getxattr on
 509	 * the root directory.  -ENODATA is ok, as this may be
 510	 * the first boot of the SELinux kernel before we have
 511	 * assigned xattr values to the filesystem.
 512	 */
 513	if (!(root_inode->i_opflags & IOP_XATTR)) {
 514		pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
 515			sb->s_id, sb->s_type->name);
 516		goto fallback;
 517	}
 518
 519	rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 520	if (rc < 0 && rc != -ENODATA) {
 521		if (rc == -EOPNOTSUPP) {
 522			pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
 523				sb->s_id, sb->s_type->name);
 524			goto fallback;
 525		} else {
 526			pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
 527				sb->s_id, sb->s_type->name, -rc);
 528			return rc;
 529		}
 530	}
 531	return 0;
 532
 533fallback:
 534	/* No xattr support - try to fallback to genfs if possible. */
 535	rc = security_genfs_sid(sb->s_type->name, "/",
 536				SECCLASS_DIR, &sid);
 537	if (rc)
 538		return -EOPNOTSUPP;
 539
 540	pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
 541		sb->s_id, sb->s_type->name);
 542	sbsec->behavior = SECURITY_FS_USE_GENFS;
 543	sbsec->sid = sid;
 544	return 0;
 545}
 546
 547static int sb_finish_set_opts(struct super_block *sb)
 548{
 549	struct superblock_security_struct *sbsec = selinux_superblock(sb);
 550	struct dentry *root = sb->s_root;
 551	struct inode *root_inode = d_backing_inode(root);
 552	int rc = 0;
 553
 554	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 555		rc = sb_check_xattr_support(sb);
 556		if (rc)
 557			return rc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 558	}
 559
 560	sbsec->flags |= SE_SBINITIALIZED;
 561
 562	/*
 563	 * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 564	 * leave the flag untouched because sb_clone_mnt_opts might be handing
 565	 * us a superblock that needs the flag to be cleared.
 566	 */
 567	if (selinux_is_sblabel_mnt(sb))
 568		sbsec->flags |= SBLABEL_MNT;
 569	else
 570		sbsec->flags &= ~SBLABEL_MNT;
 571
 572	/* Initialize the root inode. */
 573	rc = inode_doinit_with_dentry(root_inode, root);
 574
 575	/* Initialize any other inodes associated with the superblock, e.g.
 576	   inodes created prior to initial policy load or inodes created
 577	   during get_sb by a pseudo filesystem that directly
 578	   populates itself. */
 579	spin_lock(&sbsec->isec_lock);
 580	while (!list_empty(&sbsec->isec_head)) {
 581		struct inode_security_struct *isec =
 582				list_first_entry(&sbsec->isec_head,
 583					   struct inode_security_struct, list);
 584		struct inode *inode = isec->inode;
 585		list_del_init(&isec->list);
 586		spin_unlock(&sbsec->isec_lock);
 587		inode = igrab(inode);
 588		if (inode) {
 589			if (!IS_PRIVATE(inode))
 590				inode_doinit_with_dentry(inode, NULL);
 591			iput(inode);
 592		}
 593		spin_lock(&sbsec->isec_lock);
 594	}
 595	spin_unlock(&sbsec->isec_lock);
 
 596	return rc;
 597}
 598
 599static int bad_option(struct superblock_security_struct *sbsec, char flag,
 600		      u32 old_sid, u32 new_sid)
 601{
 602	char mnt_flags = sbsec->flags & SE_MNTMASK;
 603
 604	/* check if the old mount command had the same options */
 605	if (sbsec->flags & SE_SBINITIALIZED)
 606		if (!(sbsec->flags & flag) ||
 607		    (old_sid != new_sid))
 608			return 1;
 609
 610	/* check if we were passed the same options twice,
 611	 * aka someone passed context=a,context=b
 612	 */
 613	if (!(sbsec->flags & SE_SBINITIALIZED))
 614		if (mnt_flags & flag)
 615			return 1;
 616	return 0;
 617}
 618
 
 
 
 
 
 
 
 
 
 
 
 619/*
 620 * Allow filesystems with binary mount data to explicitly set mount point
 621 * labeling information.
 622 */
 623static int selinux_set_mnt_opts(struct super_block *sb,
 624				void *mnt_opts,
 625				unsigned long kern_flags,
 626				unsigned long *set_kern_flags)
 627{
 628	const struct cred *cred = current_cred();
 629	struct superblock_security_struct *sbsec = selinux_superblock(sb);
 630	struct dentry *root = sb->s_root;
 631	struct selinux_mnt_opts *opts = mnt_opts;
 632	struct inode_security_struct *root_isec;
 633	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 634	u32 defcontext_sid = 0;
 635	int rc = 0;
 636
 637	/*
 638	 * Specifying internal flags without providing a place to
 639	 * place the results is not allowed
 640	 */
 641	if (kern_flags && !set_kern_flags)
 642		return -EINVAL;
 643
 644	mutex_lock(&sbsec->lock);
 645
 646	if (!selinux_initialized()) {
 647		if (!opts) {
 648			/* Defer initialization until selinux_complete_init,
 649			   after the initial policy is loaded and the security
 650			   server is ready to handle calls. */
 651			if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
 652				sbsec->flags |= SE_SBNATIVE;
 653				*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 654			}
 655			goto out;
 656		}
 657		rc = -EINVAL;
 658		pr_warn("SELinux: Unable to set superblock options "
 659			"before the security server is initialized\n");
 660		goto out;
 661	}
 
 
 
 
 
 
 662
 663	/*
 664	 * Binary mount data FS will come through this function twice.  Once
 665	 * from an explicit call and once from the generic calls from the vfs.
 666	 * Since the generic VFS calls will not contain any security mount data
 667	 * we need to skip the double mount verification.
 668	 *
 669	 * This does open a hole in which we will not notice if the first
 670	 * mount using this sb set explicit options and a second mount using
 671	 * this sb does not set any security options.  (The first options
 672	 * will be used for both mounts)
 673	 */
 674	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 675	    && !opts)
 676		goto out;
 677
 678	root_isec = backing_inode_security_novalidate(root);
 679
 680	/*
 681	 * parse the mount options, check if they are valid sids.
 682	 * also check if someone is trying to mount the same sb more
 683	 * than once with different security options.
 684	 */
 685	if (opts) {
 686		if (opts->fscontext_sid) {
 687			fscontext_sid = opts->fscontext_sid;
 
 
 688			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 689					fscontext_sid))
 690				goto out_double_mount;
 691			sbsec->flags |= FSCONTEXT_MNT;
 692		}
 693		if (opts->context_sid) {
 694			context_sid = opts->context_sid;
 
 
 695			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 696					context_sid))
 697				goto out_double_mount;
 698			sbsec->flags |= CONTEXT_MNT;
 699		}
 700		if (opts->rootcontext_sid) {
 701			rootcontext_sid = opts->rootcontext_sid;
 
 
 702			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 703					rootcontext_sid))
 704				goto out_double_mount;
 705			sbsec->flags |= ROOTCONTEXT_MNT;
 706		}
 707		if (opts->defcontext_sid) {
 708			defcontext_sid = opts->defcontext_sid;
 
 
 709			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 710					defcontext_sid))
 711				goto out_double_mount;
 712			sbsec->flags |= DEFCONTEXT_MNT;
 713		}
 714	}
 715
 716	if (sbsec->flags & SE_SBINITIALIZED) {
 717		/* previously mounted with options, but not on this attempt? */
 718		if ((sbsec->flags & SE_MNTMASK) && !opts)
 719			goto out_double_mount;
 720		rc = 0;
 721		goto out;
 722	}
 723
 724	if (strcmp(sb->s_type->name, "proc") == 0)
 725		sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 726
 727	if (!strcmp(sb->s_type->name, "debugfs") ||
 728	    !strcmp(sb->s_type->name, "tracefs") ||
 729	    !strcmp(sb->s_type->name, "binder") ||
 730	    !strcmp(sb->s_type->name, "bpf") ||
 731	    !strcmp(sb->s_type->name, "pstore") ||
 732	    !strcmp(sb->s_type->name, "securityfs"))
 733		sbsec->flags |= SE_SBGENFS;
 734
 735	if (!strcmp(sb->s_type->name, "sysfs") ||
 736	    !strcmp(sb->s_type->name, "cgroup") ||
 737	    !strcmp(sb->s_type->name, "cgroup2"))
 738		sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
 739
 740	if (!sbsec->behavior) {
 741		/*
 742		 * Determine the labeling behavior to use for this
 743		 * filesystem type.
 744		 */
 745		rc = security_fs_use(sb);
 746		if (rc) {
 747			pr_warn("%s: security_fs_use(%s) returned %d\n",
 748					__func__, sb->s_type->name, rc);
 749			goto out;
 750		}
 751	}
 752
 753	/*
 754	 * If this is a user namespace mount and the filesystem type is not
 755	 * explicitly whitelisted, then no contexts are allowed on the command
 756	 * line and security labels must be ignored.
 757	 */
 758	if (sb->s_user_ns != &init_user_ns &&
 759	    strcmp(sb->s_type->name, "tmpfs") &&
 760	    strcmp(sb->s_type->name, "ramfs") &&
 761	    strcmp(sb->s_type->name, "devpts") &&
 762	    strcmp(sb->s_type->name, "overlay")) {
 763		if (context_sid || fscontext_sid || rootcontext_sid ||
 764		    defcontext_sid) {
 765			rc = -EACCES;
 766			goto out;
 767		}
 768		if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 769			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 770			rc = security_transition_sid(current_sid(),
 
 771						     current_sid(),
 772						     SECCLASS_FILE, NULL,
 773						     &sbsec->mntpoint_sid);
 774			if (rc)
 775				goto out;
 776		}
 777		goto out_set_opts;
 778	}
 779
 780	/* sets the context of the superblock for the fs being mounted. */
 781	if (fscontext_sid) {
 782		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 783		if (rc)
 784			goto out;
 785
 786		sbsec->sid = fscontext_sid;
 787	}
 788
 789	/*
 790	 * Switch to using mount point labeling behavior.
 791	 * sets the label used on all file below the mountpoint, and will set
 792	 * the superblock context if not already set.
 793	 */
 794	if (sbsec->flags & SE_SBNATIVE) {
 795		/*
 796		 * This means we are initializing a superblock that has been
 797		 * mounted before the SELinux was initialized and the
 798		 * filesystem requested native labeling. We had already
 799		 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags
 800		 * in the original mount attempt, so now we just need to set
 801		 * the SECURITY_FS_USE_NATIVE behavior.
 802		 */
 803		sbsec->behavior = SECURITY_FS_USE_NATIVE;
 804	} else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 805		sbsec->behavior = SECURITY_FS_USE_NATIVE;
 806		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 807	}
 808
 809	if (context_sid) {
 810		if (!fscontext_sid) {
 811			rc = may_context_mount_sb_relabel(context_sid, sbsec,
 812							  cred);
 813			if (rc)
 814				goto out;
 815			sbsec->sid = context_sid;
 816		} else {
 817			rc = may_context_mount_inode_relabel(context_sid, sbsec,
 818							     cred);
 819			if (rc)
 820				goto out;
 821		}
 822		if (!rootcontext_sid)
 823			rootcontext_sid = context_sid;
 824
 825		sbsec->mntpoint_sid = context_sid;
 826		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 827	}
 828
 829	if (rootcontext_sid) {
 830		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 831						     cred);
 832		if (rc)
 833			goto out;
 834
 835		root_isec->sid = rootcontext_sid;
 836		root_isec->initialized = LABEL_INITIALIZED;
 837	}
 838
 839	if (defcontext_sid) {
 840		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 841			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 842			rc = -EINVAL;
 843			pr_warn("SELinux: defcontext option is "
 844			       "invalid for this filesystem type\n");
 845			goto out;
 846		}
 847
 848		if (defcontext_sid != sbsec->def_sid) {
 849			rc = may_context_mount_inode_relabel(defcontext_sid,
 850							     sbsec, cred);
 851			if (rc)
 852				goto out;
 853		}
 854
 855		sbsec->def_sid = defcontext_sid;
 856	}
 857
 858out_set_opts:
 859	rc = sb_finish_set_opts(sb);
 860out:
 861	mutex_unlock(&sbsec->lock);
 862	return rc;
 863out_double_mount:
 864	rc = -EINVAL;
 865	pr_warn("SELinux: mount invalid.  Same superblock, different "
 866	       "security settings for (dev %s, type %s)\n", sb->s_id,
 867	       sb->s_type->name);
 868	goto out;
 869}
 870
 871static int selinux_cmp_sb_context(const struct super_block *oldsb,
 872				    const struct super_block *newsb)
 873{
 874	struct superblock_security_struct *old = selinux_superblock(oldsb);
 875	struct superblock_security_struct *new = selinux_superblock(newsb);
 876	char oldflags = old->flags & SE_MNTMASK;
 877	char newflags = new->flags & SE_MNTMASK;
 878
 879	if (oldflags != newflags)
 880		goto mismatch;
 881	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 882		goto mismatch;
 883	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 884		goto mismatch;
 885	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 886		goto mismatch;
 887	if (oldflags & ROOTCONTEXT_MNT) {
 888		struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 889		struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 890		if (oldroot->sid != newroot->sid)
 891			goto mismatch;
 892	}
 893	return 0;
 894mismatch:
 895	pr_warn("SELinux: mount invalid.  Same superblock, "
 896			    "different security settings for (dev %s, "
 897			    "type %s)\n", newsb->s_id, newsb->s_type->name);
 898	return -EBUSY;
 899}
 900
 901static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 902					struct super_block *newsb,
 903					unsigned long kern_flags,
 904					unsigned long *set_kern_flags)
 905{
 906	int rc = 0;
 907	const struct superblock_security_struct *oldsbsec =
 908						selinux_superblock(oldsb);
 909	struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
 910
 911	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
 912	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
 913	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
 914
 915	/*
 
 
 
 
 
 
 
 916	 * Specifying internal flags without providing a place to
 917	 * place the results is not allowed.
 918	 */
 919	if (kern_flags && !set_kern_flags)
 920		return -EINVAL;
 921
 922	mutex_lock(&newsbsec->lock);
 923
 924	/*
 925	 * if the parent was able to be mounted it clearly had no special lsm
 926	 * mount options.  thus we can safely deal with this superblock later
 927	 */
 928	if (!selinux_initialized()) {
 929		if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
 930			newsbsec->flags |= SE_SBNATIVE;
 931			*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 932		}
 933		goto out;
 934	}
 935
 936	/* how can we clone if the old one wasn't set up?? */
 937	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 938
 939	/* if fs is reusing a sb, make sure that the contexts match */
 940	if (newsbsec->flags & SE_SBINITIALIZED) {
 941		mutex_unlock(&newsbsec->lock);
 942		if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
 943			*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 944		return selinux_cmp_sb_context(oldsb, newsb);
 945	}
 946
 
 
 947	newsbsec->flags = oldsbsec->flags;
 948
 949	newsbsec->sid = oldsbsec->sid;
 950	newsbsec->def_sid = oldsbsec->def_sid;
 951	newsbsec->behavior = oldsbsec->behavior;
 952
 953	if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
 954		!(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
 955		rc = security_fs_use(newsb);
 956		if (rc)
 957			goto out;
 958	}
 959
 960	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
 961		newsbsec->behavior = SECURITY_FS_USE_NATIVE;
 962		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 963	}
 964
 965	if (set_context) {
 966		u32 sid = oldsbsec->mntpoint_sid;
 967
 968		if (!set_fscontext)
 969			newsbsec->sid = sid;
 970		if (!set_rootcontext) {
 971			struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 972			newisec->sid = sid;
 973		}
 974		newsbsec->mntpoint_sid = sid;
 975	}
 976	if (set_rootcontext) {
 977		const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
 978		struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 979
 980		newisec->sid = oldisec->sid;
 981	}
 982
 983	sb_finish_set_opts(newsb);
 984out:
 985	mutex_unlock(&newsbsec->lock);
 986	return rc;
 987}
 988
 989/*
 990 * NOTE: the caller is responsible for freeing the memory even if on error.
 991 */
 992static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 993{
 994	struct selinux_mnt_opts *opts = *mnt_opts;
 995	u32 *dst_sid;
 996	int rc;
 997
 998	if (token == Opt_seclabel)
 999		/* eaten and completely ignored */
1000		return 0;
1001	if (!s)
1002		return -EINVAL;
1003
1004	if (!selinux_initialized()) {
1005		pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
1006		return -EINVAL;
1007	}
1008
1009	if (!opts) {
1010		opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1011		if (!opts)
1012			return -ENOMEM;
1013		*mnt_opts = opts;
1014	}
1015
 
1016	switch (token) {
1017	case Opt_context:
1018		if (opts->context_sid || opts->defcontext_sid)
1019			goto err;
1020		dst_sid = &opts->context_sid;
1021		break;
1022	case Opt_fscontext:
1023		if (opts->fscontext_sid)
1024			goto err;
1025		dst_sid = &opts->fscontext_sid;
1026		break;
1027	case Opt_rootcontext:
1028		if (opts->rootcontext_sid)
1029			goto err;
1030		dst_sid = &opts->rootcontext_sid;
1031		break;
1032	case Opt_defcontext:
1033		if (opts->context_sid || opts->defcontext_sid)
1034			goto err;
1035		dst_sid = &opts->defcontext_sid;
1036		break;
1037	default:
1038		WARN_ON(1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1039		return -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 
1040	}
1041	rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL);
1042	if (rc)
1043		pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1044			s, rc);
1045	return rc;
1046
1047err:
1048	pr_warn(SEL_MOUNT_FAIL_MSG);
1049	return -EINVAL;
 
 
 
1050}
1051
1052static int show_sid(struct seq_file *m, u32 sid)
1053{
1054	char *context = NULL;
1055	u32 len;
1056	int rc;
1057
1058	rc = security_sid_to_context(sid, &context, &len);
 
1059	if (!rc) {
1060		bool has_comma = strchr(context, ',');
1061
1062		seq_putc(m, '=');
1063		if (has_comma)
1064			seq_putc(m, '\"');
1065		seq_escape(m, context, "\"\n\\");
1066		if (has_comma)
1067			seq_putc(m, '\"');
1068	}
1069	kfree(context);
1070	return rc;
1071}
1072
1073static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1074{
1075	struct superblock_security_struct *sbsec = selinux_superblock(sb);
1076	int rc;
1077
1078	if (!(sbsec->flags & SE_SBINITIALIZED))
1079		return 0;
1080
1081	if (!selinux_initialized())
1082		return 0;
1083
1084	if (sbsec->flags & FSCONTEXT_MNT) {
1085		seq_putc(m, ',');
1086		seq_puts(m, FSCONTEXT_STR);
1087		rc = show_sid(m, sbsec->sid);
1088		if (rc)
1089			return rc;
1090	}
1091	if (sbsec->flags & CONTEXT_MNT) {
1092		seq_putc(m, ',');
1093		seq_puts(m, CONTEXT_STR);
1094		rc = show_sid(m, sbsec->mntpoint_sid);
1095		if (rc)
1096			return rc;
1097	}
1098	if (sbsec->flags & DEFCONTEXT_MNT) {
1099		seq_putc(m, ',');
1100		seq_puts(m, DEFCONTEXT_STR);
1101		rc = show_sid(m, sbsec->def_sid);
1102		if (rc)
1103			return rc;
1104	}
1105	if (sbsec->flags & ROOTCONTEXT_MNT) {
1106		struct dentry *root = sb->s_root;
1107		struct inode_security_struct *isec = backing_inode_security(root);
1108		seq_putc(m, ',');
1109		seq_puts(m, ROOTCONTEXT_STR);
1110		rc = show_sid(m, isec->sid);
1111		if (rc)
1112			return rc;
1113	}
1114	if (sbsec->flags & SBLABEL_MNT) {
1115		seq_putc(m, ',');
1116		seq_puts(m, SECLABEL_STR);
1117	}
1118	return 0;
1119}
1120
1121static inline u16 inode_mode_to_security_class(umode_t mode)
1122{
1123	switch (mode & S_IFMT) {
1124	case S_IFSOCK:
1125		return SECCLASS_SOCK_FILE;
1126	case S_IFLNK:
1127		return SECCLASS_LNK_FILE;
1128	case S_IFREG:
1129		return SECCLASS_FILE;
1130	case S_IFBLK:
1131		return SECCLASS_BLK_FILE;
1132	case S_IFDIR:
1133		return SECCLASS_DIR;
1134	case S_IFCHR:
1135		return SECCLASS_CHR_FILE;
1136	case S_IFIFO:
1137		return SECCLASS_FIFO_FILE;
1138
1139	}
1140
1141	return SECCLASS_FILE;
1142}
1143
1144static inline int default_protocol_stream(int protocol)
1145{
1146	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1147		protocol == IPPROTO_MPTCP);
1148}
1149
1150static inline int default_protocol_dgram(int protocol)
1151{
1152	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1153}
1154
1155static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1156{
1157	bool extsockclass = selinux_policycap_extsockclass();
1158
1159	switch (family) {
1160	case PF_UNIX:
1161		switch (type) {
1162		case SOCK_STREAM:
1163		case SOCK_SEQPACKET:
1164			return SECCLASS_UNIX_STREAM_SOCKET;
1165		case SOCK_DGRAM:
1166		case SOCK_RAW:
1167			return SECCLASS_UNIX_DGRAM_SOCKET;
1168		}
1169		break;
1170	case PF_INET:
1171	case PF_INET6:
1172		switch (type) {
1173		case SOCK_STREAM:
1174		case SOCK_SEQPACKET:
1175			if (default_protocol_stream(protocol))
1176				return SECCLASS_TCP_SOCKET;
1177			else if (extsockclass && protocol == IPPROTO_SCTP)
1178				return SECCLASS_SCTP_SOCKET;
1179			else
1180				return SECCLASS_RAWIP_SOCKET;
1181		case SOCK_DGRAM:
1182			if (default_protocol_dgram(protocol))
1183				return SECCLASS_UDP_SOCKET;
1184			else if (extsockclass && (protocol == IPPROTO_ICMP ||
1185						  protocol == IPPROTO_ICMPV6))
1186				return SECCLASS_ICMP_SOCKET;
1187			else
1188				return SECCLASS_RAWIP_SOCKET;
1189		case SOCK_DCCP:
1190			return SECCLASS_DCCP_SOCKET;
1191		default:
1192			return SECCLASS_RAWIP_SOCKET;
1193		}
1194		break;
1195	case PF_NETLINK:
1196		switch (protocol) {
1197		case NETLINK_ROUTE:
1198			return SECCLASS_NETLINK_ROUTE_SOCKET;
1199		case NETLINK_SOCK_DIAG:
1200			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1201		case NETLINK_NFLOG:
1202			return SECCLASS_NETLINK_NFLOG_SOCKET;
1203		case NETLINK_XFRM:
1204			return SECCLASS_NETLINK_XFRM_SOCKET;
1205		case NETLINK_SELINUX:
1206			return SECCLASS_NETLINK_SELINUX_SOCKET;
1207		case NETLINK_ISCSI:
1208			return SECCLASS_NETLINK_ISCSI_SOCKET;
1209		case NETLINK_AUDIT:
1210			return SECCLASS_NETLINK_AUDIT_SOCKET;
1211		case NETLINK_FIB_LOOKUP:
1212			return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1213		case NETLINK_CONNECTOR:
1214			return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1215		case NETLINK_NETFILTER:
1216			return SECCLASS_NETLINK_NETFILTER_SOCKET;
1217		case NETLINK_DNRTMSG:
1218			return SECCLASS_NETLINK_DNRT_SOCKET;
1219		case NETLINK_KOBJECT_UEVENT:
1220			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1221		case NETLINK_GENERIC:
1222			return SECCLASS_NETLINK_GENERIC_SOCKET;
1223		case NETLINK_SCSITRANSPORT:
1224			return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1225		case NETLINK_RDMA:
1226			return SECCLASS_NETLINK_RDMA_SOCKET;
1227		case NETLINK_CRYPTO:
1228			return SECCLASS_NETLINK_CRYPTO_SOCKET;
1229		default:
1230			return SECCLASS_NETLINK_SOCKET;
1231		}
1232	case PF_PACKET:
1233		return SECCLASS_PACKET_SOCKET;
1234	case PF_KEY:
1235		return SECCLASS_KEY_SOCKET;
1236	case PF_APPLETALK:
1237		return SECCLASS_APPLETALK_SOCKET;
1238	}
1239
1240	if (extsockclass) {
1241		switch (family) {
1242		case PF_AX25:
1243			return SECCLASS_AX25_SOCKET;
1244		case PF_IPX:
1245			return SECCLASS_IPX_SOCKET;
1246		case PF_NETROM:
1247			return SECCLASS_NETROM_SOCKET;
1248		case PF_ATMPVC:
1249			return SECCLASS_ATMPVC_SOCKET;
1250		case PF_X25:
1251			return SECCLASS_X25_SOCKET;
1252		case PF_ROSE:
1253			return SECCLASS_ROSE_SOCKET;
1254		case PF_DECnet:
1255			return SECCLASS_DECNET_SOCKET;
1256		case PF_ATMSVC:
1257			return SECCLASS_ATMSVC_SOCKET;
1258		case PF_RDS:
1259			return SECCLASS_RDS_SOCKET;
1260		case PF_IRDA:
1261			return SECCLASS_IRDA_SOCKET;
1262		case PF_PPPOX:
1263			return SECCLASS_PPPOX_SOCKET;
1264		case PF_LLC:
1265			return SECCLASS_LLC_SOCKET;
1266		case PF_CAN:
1267			return SECCLASS_CAN_SOCKET;
1268		case PF_TIPC:
1269			return SECCLASS_TIPC_SOCKET;
1270		case PF_BLUETOOTH:
1271			return SECCLASS_BLUETOOTH_SOCKET;
1272		case PF_IUCV:
1273			return SECCLASS_IUCV_SOCKET;
1274		case PF_RXRPC:
1275			return SECCLASS_RXRPC_SOCKET;
1276		case PF_ISDN:
1277			return SECCLASS_ISDN_SOCKET;
1278		case PF_PHONET:
1279			return SECCLASS_PHONET_SOCKET;
1280		case PF_IEEE802154:
1281			return SECCLASS_IEEE802154_SOCKET;
1282		case PF_CAIF:
1283			return SECCLASS_CAIF_SOCKET;
1284		case PF_ALG:
1285			return SECCLASS_ALG_SOCKET;
1286		case PF_NFC:
1287			return SECCLASS_NFC_SOCKET;
1288		case PF_VSOCK:
1289			return SECCLASS_VSOCK_SOCKET;
1290		case PF_KCM:
1291			return SECCLASS_KCM_SOCKET;
1292		case PF_QIPCRTR:
1293			return SECCLASS_QIPCRTR_SOCKET;
1294		case PF_SMC:
1295			return SECCLASS_SMC_SOCKET;
1296		case PF_XDP:
1297			return SECCLASS_XDP_SOCKET;
1298		case PF_MCTP:
1299			return SECCLASS_MCTP_SOCKET;
1300#if PF_MAX > 46
1301#error New address family defined, please update this function.
1302#endif
1303		}
1304	}
1305
1306	return SECCLASS_SOCKET;
1307}
1308
1309static int selinux_genfs_get_sid(struct dentry *dentry,
1310				 u16 tclass,
1311				 u16 flags,
1312				 u32 *sid)
1313{
1314	int rc;
1315	struct super_block *sb = dentry->d_sb;
1316	char *buffer, *path;
1317
1318	buffer = (char *)__get_free_page(GFP_KERNEL);
1319	if (!buffer)
1320		return -ENOMEM;
1321
1322	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1323	if (IS_ERR(path))
1324		rc = PTR_ERR(path);
1325	else {
1326		if (flags & SE_SBPROC) {
1327			/* each process gets a /proc/PID/ entry. Strip off the
1328			 * PID part to get a valid selinux labeling.
1329			 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1330			while (path[1] >= '0' && path[1] <= '9') {
1331				path[1] = '/';
1332				path++;
1333			}
1334		}
1335		rc = security_genfs_sid(sb->s_type->name,
1336					path, tclass, sid);
1337		if (rc == -ENOENT) {
1338			/* No match in policy, mark as unlabeled. */
1339			*sid = SECINITSID_UNLABELED;
1340			rc = 0;
1341		}
1342	}
1343	free_page((unsigned long)buffer);
1344	return rc;
1345}
1346
1347static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1348				  u32 def_sid, u32 *sid)
1349{
1350#define INITCONTEXTLEN 255
1351	char *context;
1352	unsigned int len;
1353	int rc;
1354
1355	len = INITCONTEXTLEN;
1356	context = kmalloc(len + 1, GFP_NOFS);
1357	if (!context)
1358		return -ENOMEM;
1359
1360	context[len] = '\0';
1361	rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1362	if (rc == -ERANGE) {
1363		kfree(context);
1364
1365		/* Need a larger buffer.  Query for the right size. */
1366		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1367		if (rc < 0)
1368			return rc;
1369
1370		len = rc;
1371		context = kmalloc(len + 1, GFP_NOFS);
1372		if (!context)
1373			return -ENOMEM;
1374
1375		context[len] = '\0';
1376		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1377				    context, len);
1378	}
1379	if (rc < 0) {
1380		kfree(context);
1381		if (rc != -ENODATA) {
1382			pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1383				__func__, -rc, inode->i_sb->s_id, inode->i_ino);
1384			return rc;
1385		}
1386		*sid = def_sid;
1387		return 0;
1388	}
1389
1390	rc = security_context_to_sid_default(context, rc, sid,
1391					     def_sid, GFP_NOFS);
1392	if (rc) {
1393		char *dev = inode->i_sb->s_id;
1394		unsigned long ino = inode->i_ino;
1395
1396		if (rc == -EINVAL) {
1397			pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s.  This indicates you may need to relabel the inode or the filesystem in question.\n",
1398					      ino, dev, context);
1399		} else {
1400			pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1401				__func__, context, -rc, dev, ino);
1402		}
1403	}
1404	kfree(context);
1405	return 0;
1406}
1407
1408/* The inode's security attributes must be initialized before first use. */
1409static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1410{
1411	struct superblock_security_struct *sbsec = NULL;
1412	struct inode_security_struct *isec = selinux_inode(inode);
1413	u32 task_sid, sid = 0;
1414	u16 sclass;
1415	struct dentry *dentry;
1416	int rc = 0;
1417
1418	if (isec->initialized == LABEL_INITIALIZED)
1419		return 0;
1420
1421	spin_lock(&isec->lock);
1422	if (isec->initialized == LABEL_INITIALIZED)
1423		goto out_unlock;
1424
1425	if (isec->sclass == SECCLASS_FILE)
1426		isec->sclass = inode_mode_to_security_class(inode->i_mode);
1427
1428	sbsec = selinux_superblock(inode->i_sb);
1429	if (!(sbsec->flags & SE_SBINITIALIZED)) {
1430		/* Defer initialization until selinux_complete_init,
1431		   after the initial policy is loaded and the security
1432		   server is ready to handle calls. */
1433		spin_lock(&sbsec->isec_lock);
1434		if (list_empty(&isec->list))
1435			list_add(&isec->list, &sbsec->isec_head);
1436		spin_unlock(&sbsec->isec_lock);
1437		goto out_unlock;
1438	}
1439
1440	sclass = isec->sclass;
1441	task_sid = isec->task_sid;
1442	sid = isec->sid;
1443	isec->initialized = LABEL_PENDING;
1444	spin_unlock(&isec->lock);
1445
1446	switch (sbsec->behavior) {
1447	/*
1448	 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels
1449	 * via xattr when called from delayed_superblock_init().
1450	 */
1451	case SECURITY_FS_USE_NATIVE:
 
1452	case SECURITY_FS_USE_XATTR:
1453		if (!(inode->i_opflags & IOP_XATTR)) {
1454			sid = sbsec->def_sid;
1455			break;
1456		}
1457		/* Need a dentry, since the xattr API requires one.
1458		   Life would be simpler if we could just pass the inode. */
1459		if (opt_dentry) {
1460			/* Called from d_instantiate or d_splice_alias. */
1461			dentry = dget(opt_dentry);
1462		} else {
1463			/*
1464			 * Called from selinux_complete_init, try to find a dentry.
1465			 * Some filesystems really want a connected one, so try
1466			 * that first.  We could split SECURITY_FS_USE_XATTR in
1467			 * two, depending upon that...
1468			 */
1469			dentry = d_find_alias(inode);
1470			if (!dentry)
1471				dentry = d_find_any_alias(inode);
1472		}
1473		if (!dentry) {
1474			/*
1475			 * this is can be hit on boot when a file is accessed
1476			 * before the policy is loaded.  When we load policy we
1477			 * may find inodes that have no dentry on the
1478			 * sbsec->isec_head list.  No reason to complain as these
1479			 * will get fixed up the next time we go through
1480			 * inode_doinit with a dentry, before these inodes could
1481			 * be used again by userspace.
1482			 */
1483			goto out_invalid;
1484		}
1485
1486		rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1487					    &sid);
1488		dput(dentry);
1489		if (rc)
1490			goto out;
1491		break;
1492	case SECURITY_FS_USE_TASK:
1493		sid = task_sid;
1494		break;
1495	case SECURITY_FS_USE_TRANS:
1496		/* Default to the fs SID. */
1497		sid = sbsec->sid;
1498
1499		/* Try to obtain a transition SID. */
1500		rc = security_transition_sid(task_sid, sid,
1501					     sclass, NULL, &sid);
1502		if (rc)
1503			goto out;
1504		break;
1505	case SECURITY_FS_USE_MNTPOINT:
1506		sid = sbsec->mntpoint_sid;
1507		break;
1508	default:
1509		/* Default to the fs superblock SID. */
1510		sid = sbsec->sid;
1511
1512		if ((sbsec->flags & SE_SBGENFS) &&
1513		     (!S_ISLNK(inode->i_mode) ||
1514		      selinux_policycap_genfs_seclabel_symlinks())) {
1515			/* We must have a dentry to determine the label on
1516			 * procfs inodes */
1517			if (opt_dentry) {
1518				/* Called from d_instantiate or
1519				 * d_splice_alias. */
1520				dentry = dget(opt_dentry);
1521			} else {
1522				/* Called from selinux_complete_init, try to
1523				 * find a dentry.  Some filesystems really want
1524				 * a connected one, so try that first.
1525				 */
1526				dentry = d_find_alias(inode);
1527				if (!dentry)
1528					dentry = d_find_any_alias(inode);
1529			}
1530			/*
1531			 * This can be hit on boot when a file is accessed
1532			 * before the policy is loaded.  When we load policy we
1533			 * may find inodes that have no dentry on the
1534			 * sbsec->isec_head list.  No reason to complain as
1535			 * these will get fixed up the next time we go through
1536			 * inode_doinit() with a dentry, before these inodes
1537			 * could be used again by userspace.
1538			 */
1539			if (!dentry)
1540				goto out_invalid;
1541			rc = selinux_genfs_get_sid(dentry, sclass,
1542						   sbsec->flags, &sid);
1543			if (rc) {
1544				dput(dentry);
1545				goto out;
1546			}
1547
1548			if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1549			    (inode->i_opflags & IOP_XATTR)) {
1550				rc = inode_doinit_use_xattr(inode, dentry,
1551							    sid, &sid);
1552				if (rc) {
1553					dput(dentry);
1554					goto out;
1555				}
1556			}
1557			dput(dentry);
1558		}
1559		break;
1560	}
1561
1562out:
1563	spin_lock(&isec->lock);
1564	if (isec->initialized == LABEL_PENDING) {
1565		if (rc) {
1566			isec->initialized = LABEL_INVALID;
1567			goto out_unlock;
1568		}
 
1569		isec->initialized = LABEL_INITIALIZED;
1570		isec->sid = sid;
1571	}
1572
1573out_unlock:
1574	spin_unlock(&isec->lock);
1575	return rc;
1576
1577out_invalid:
1578	spin_lock(&isec->lock);
1579	if (isec->initialized == LABEL_PENDING) {
1580		isec->initialized = LABEL_INVALID;
1581		isec->sid = sid;
1582	}
1583	spin_unlock(&isec->lock);
1584	return 0;
1585}
1586
1587/* Convert a Linux signal to an access vector. */
1588static inline u32 signal_to_av(int sig)
1589{
1590	u32 perm = 0;
1591
1592	switch (sig) {
1593	case SIGCHLD:
1594		/* Commonly granted from child to parent. */
1595		perm = PROCESS__SIGCHLD;
1596		break;
1597	case SIGKILL:
1598		/* Cannot be caught or ignored */
1599		perm = PROCESS__SIGKILL;
1600		break;
1601	case SIGSTOP:
1602		/* Cannot be caught or ignored */
1603		perm = PROCESS__SIGSTOP;
1604		break;
1605	default:
1606		/* All other signals. */
1607		perm = PROCESS__SIGNAL;
1608		break;
1609	}
1610
1611	return perm;
1612}
1613
1614#if CAP_LAST_CAP > 63
1615#error Fix SELinux to handle capabilities > 63.
1616#endif
1617
1618/* Check whether a task is allowed to use a capability. */
1619static int cred_has_capability(const struct cred *cred,
1620			       int cap, unsigned int opts, bool initns)
1621{
1622	struct common_audit_data ad;
1623	struct av_decision avd;
1624	u16 sclass;
1625	u32 sid = cred_sid(cred);
1626	u32 av = CAP_TO_MASK(cap);
1627	int rc;
1628
1629	ad.type = LSM_AUDIT_DATA_CAP;
1630	ad.u.cap = cap;
1631
1632	switch (CAP_TO_INDEX(cap)) {
1633	case 0:
1634		sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1635		break;
1636	case 1:
1637		sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1638		break;
1639	default:
1640		pr_err("SELinux:  out of range capability %d\n", cap);
1641		BUG();
1642		return -EINVAL;
1643	}
1644
1645	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
 
1646	if (!(opts & CAP_OPT_NOAUDIT)) {
1647		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
 
1648		if (rc2)
1649			return rc2;
1650	}
1651	return rc;
1652}
1653
1654/* Check whether a task has a particular permission to an inode.
1655   The 'adp' parameter is optional and allows other audit
1656   data to be passed (e.g. the dentry). */
1657static int inode_has_perm(const struct cred *cred,
1658			  struct inode *inode,
1659			  u32 perms,
1660			  struct common_audit_data *adp)
1661{
1662	struct inode_security_struct *isec;
1663	u32 sid;
1664
 
 
1665	if (unlikely(IS_PRIVATE(inode)))
1666		return 0;
1667
1668	sid = cred_sid(cred);
1669	isec = selinux_inode(inode);
1670
1671	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
 
1672}
1673
1674/* Same as inode_has_perm, but pass explicit audit data containing
1675   the dentry to help the auditing code to more easily generate the
1676   pathname if needed. */
1677static inline int dentry_has_perm(const struct cred *cred,
1678				  struct dentry *dentry,
1679				  u32 av)
1680{
1681	struct inode *inode = d_backing_inode(dentry);
1682	struct common_audit_data ad;
1683
1684	ad.type = LSM_AUDIT_DATA_DENTRY;
1685	ad.u.dentry = dentry;
1686	__inode_security_revalidate(inode, dentry, true);
1687	return inode_has_perm(cred, inode, av, &ad);
1688}
1689
1690/* Same as inode_has_perm, but pass explicit audit data containing
1691   the path to help the auditing code to more easily generate the
1692   pathname if needed. */
1693static inline int path_has_perm(const struct cred *cred,
1694				const struct path *path,
1695				u32 av)
1696{
1697	struct inode *inode = d_backing_inode(path->dentry);
1698	struct common_audit_data ad;
1699
1700	ad.type = LSM_AUDIT_DATA_PATH;
1701	ad.u.path = *path;
1702	__inode_security_revalidate(inode, path->dentry, true);
1703	return inode_has_perm(cred, inode, av, &ad);
1704}
1705
1706/* Same as path_has_perm, but uses the inode from the file struct. */
1707static inline int file_path_has_perm(const struct cred *cred,
1708				     struct file *file,
1709				     u32 av)
1710{
1711	struct common_audit_data ad;
1712
1713	ad.type = LSM_AUDIT_DATA_FILE;
1714	ad.u.file = file;
1715	return inode_has_perm(cred, file_inode(file), av, &ad);
1716}
1717
1718#ifdef CONFIG_BPF_SYSCALL
1719static int bpf_fd_pass(const struct file *file, u32 sid);
1720#endif
1721
1722/* Check whether a task can use an open file descriptor to
1723   access an inode in a given way.  Check access to the
1724   descriptor itself, and then use dentry_has_perm to
1725   check a particular permission to the file.
1726   Access to the descriptor is implicitly granted if it
1727   has the same SID as the process.  If av is zero, then
1728   access to the file is not checked, e.g. for cases
1729   where only the descriptor is affected like seek. */
1730static int file_has_perm(const struct cred *cred,
1731			 struct file *file,
1732			 u32 av)
1733{
1734	struct file_security_struct *fsec = selinux_file(file);
1735	struct inode *inode = file_inode(file);
1736	struct common_audit_data ad;
1737	u32 sid = cred_sid(cred);
1738	int rc;
1739
1740	ad.type = LSM_AUDIT_DATA_FILE;
1741	ad.u.file = file;
1742
1743	if (sid != fsec->sid) {
1744		rc = avc_has_perm(sid, fsec->sid,
 
1745				  SECCLASS_FD,
1746				  FD__USE,
1747				  &ad);
1748		if (rc)
1749			goto out;
1750	}
1751
1752#ifdef CONFIG_BPF_SYSCALL
1753	rc = bpf_fd_pass(file, cred_sid(cred));
1754	if (rc)
1755		return rc;
1756#endif
1757
1758	/* av is zero if only checking access to the descriptor. */
1759	rc = 0;
1760	if (av)
1761		rc = inode_has_perm(cred, inode, av, &ad);
1762
1763out:
1764	return rc;
1765}
1766
1767/*
1768 * Determine the label for an inode that might be unioned.
1769 */
1770static int
1771selinux_determine_inode_label(const struct task_security_struct *tsec,
1772				 struct inode *dir,
1773				 const struct qstr *name, u16 tclass,
1774				 u32 *_new_isid)
1775{
1776	const struct superblock_security_struct *sbsec =
1777						selinux_superblock(dir->i_sb);
1778
1779	if ((sbsec->flags & SE_SBINITIALIZED) &&
1780	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1781		*_new_isid = sbsec->mntpoint_sid;
1782	} else if ((sbsec->flags & SBLABEL_MNT) &&
1783		   tsec->create_sid) {
1784		*_new_isid = tsec->create_sid;
1785	} else {
1786		const struct inode_security_struct *dsec = inode_security(dir);
1787		return security_transition_sid(tsec->sid,
1788					       dsec->sid, tclass,
1789					       name, _new_isid);
1790	}
1791
1792	return 0;
1793}
1794
1795/* Check whether a task can create a file. */
1796static int may_create(struct inode *dir,
1797		      struct dentry *dentry,
1798		      u16 tclass)
1799{
1800	const struct task_security_struct *tsec = selinux_cred(current_cred());
1801	struct inode_security_struct *dsec;
1802	struct superblock_security_struct *sbsec;
1803	u32 sid, newsid;
1804	struct common_audit_data ad;
1805	int rc;
1806
1807	dsec = inode_security(dir);
1808	sbsec = selinux_superblock(dir->i_sb);
1809
1810	sid = tsec->sid;
1811
1812	ad.type = LSM_AUDIT_DATA_DENTRY;
1813	ad.u.dentry = dentry;
1814
1815	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
 
1816			  DIR__ADD_NAME | DIR__SEARCH,
1817			  &ad);
1818	if (rc)
1819		return rc;
1820
1821	rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1822					   &newsid);
1823	if (rc)
1824		return rc;
1825
1826	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
 
1827	if (rc)
1828		return rc;
1829
1830	return avc_has_perm(newsid, sbsec->sid,
 
1831			    SECCLASS_FILESYSTEM,
1832			    FILESYSTEM__ASSOCIATE, &ad);
1833}
1834
1835#define MAY_LINK	0
1836#define MAY_UNLINK	1
1837#define MAY_RMDIR	2
1838
1839/* Check whether a task can link, unlink, or rmdir a file/directory. */
1840static int may_link(struct inode *dir,
1841		    struct dentry *dentry,
1842		    int kind)
1843
1844{
1845	struct inode_security_struct *dsec, *isec;
1846	struct common_audit_data ad;
1847	u32 sid = current_sid();
1848	u32 av;
1849	int rc;
1850
1851	dsec = inode_security(dir);
1852	isec = backing_inode_security(dentry);
1853
1854	ad.type = LSM_AUDIT_DATA_DENTRY;
1855	ad.u.dentry = dentry;
1856
1857	av = DIR__SEARCH;
1858	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1859	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
 
1860	if (rc)
1861		return rc;
1862
1863	switch (kind) {
1864	case MAY_LINK:
1865		av = FILE__LINK;
1866		break;
1867	case MAY_UNLINK:
1868		av = FILE__UNLINK;
1869		break;
1870	case MAY_RMDIR:
1871		av = DIR__RMDIR;
1872		break;
1873	default:
1874		pr_warn("SELinux: %s:  unrecognized kind %d\n",
1875			__func__, kind);
1876		return 0;
1877	}
1878
1879	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
 
1880	return rc;
1881}
1882
1883static inline int may_rename(struct inode *old_dir,
1884			     struct dentry *old_dentry,
1885			     struct inode *new_dir,
1886			     struct dentry *new_dentry)
1887{
1888	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1889	struct common_audit_data ad;
1890	u32 sid = current_sid();
1891	u32 av;
1892	int old_is_dir, new_is_dir;
1893	int rc;
1894
1895	old_dsec = inode_security(old_dir);
1896	old_isec = backing_inode_security(old_dentry);
1897	old_is_dir = d_is_dir(old_dentry);
1898	new_dsec = inode_security(new_dir);
1899
1900	ad.type = LSM_AUDIT_DATA_DENTRY;
1901
1902	ad.u.dentry = old_dentry;
1903	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
 
1904			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1905	if (rc)
1906		return rc;
1907	rc = avc_has_perm(sid, old_isec->sid,
 
1908			  old_isec->sclass, FILE__RENAME, &ad);
1909	if (rc)
1910		return rc;
1911	if (old_is_dir && new_dir != old_dir) {
1912		rc = avc_has_perm(sid, old_isec->sid,
 
1913				  old_isec->sclass, DIR__REPARENT, &ad);
1914		if (rc)
1915			return rc;
1916	}
1917
1918	ad.u.dentry = new_dentry;
1919	av = DIR__ADD_NAME | DIR__SEARCH;
1920	if (d_is_positive(new_dentry))
1921		av |= DIR__REMOVE_NAME;
1922	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
 
1923	if (rc)
1924		return rc;
1925	if (d_is_positive(new_dentry)) {
1926		new_isec = backing_inode_security(new_dentry);
1927		new_is_dir = d_is_dir(new_dentry);
1928		rc = avc_has_perm(sid, new_isec->sid,
 
1929				  new_isec->sclass,
1930				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1931		if (rc)
1932			return rc;
1933	}
1934
1935	return 0;
1936}
1937
1938/* Check whether a task can perform a filesystem operation. */
1939static int superblock_has_perm(const struct cred *cred,
1940			       const struct super_block *sb,
1941			       u32 perms,
1942			       struct common_audit_data *ad)
1943{
1944	struct superblock_security_struct *sbsec;
1945	u32 sid = cred_sid(cred);
1946
1947	sbsec = selinux_superblock(sb);
1948	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
 
1949}
1950
1951/* Convert a Linux mode and permission mask to an access vector. */
1952static inline u32 file_mask_to_av(int mode, int mask)
1953{
1954	u32 av = 0;
1955
1956	if (!S_ISDIR(mode)) {
1957		if (mask & MAY_EXEC)
1958			av |= FILE__EXECUTE;
1959		if (mask & MAY_READ)
1960			av |= FILE__READ;
1961
1962		if (mask & MAY_APPEND)
1963			av |= FILE__APPEND;
1964		else if (mask & MAY_WRITE)
1965			av |= FILE__WRITE;
1966
1967	} else {
1968		if (mask & MAY_EXEC)
1969			av |= DIR__SEARCH;
1970		if (mask & MAY_WRITE)
1971			av |= DIR__WRITE;
1972		if (mask & MAY_READ)
1973			av |= DIR__READ;
1974	}
1975
1976	return av;
1977}
1978
1979/* Convert a Linux file to an access vector. */
1980static inline u32 file_to_av(const struct file *file)
1981{
1982	u32 av = 0;
1983
1984	if (file->f_mode & FMODE_READ)
1985		av |= FILE__READ;
1986	if (file->f_mode & FMODE_WRITE) {
1987		if (file->f_flags & O_APPEND)
1988			av |= FILE__APPEND;
1989		else
1990			av |= FILE__WRITE;
1991	}
1992	if (!av) {
1993		/*
1994		 * Special file opened with flags 3 for ioctl-only use.
1995		 */
1996		av = FILE__IOCTL;
1997	}
1998
1999	return av;
2000}
2001
2002/*
2003 * Convert a file to an access vector and include the correct
2004 * open permission.
2005 */
2006static inline u32 open_file_to_av(struct file *file)
2007{
2008	u32 av = file_to_av(file);
2009	struct inode *inode = file_inode(file);
2010
2011	if (selinux_policycap_openperm() &&
2012	    inode->i_sb->s_magic != SOCKFS_MAGIC)
2013		av |= FILE__OPEN;
2014
2015	return av;
2016}
2017
2018/* Hook functions begin here. */
2019
2020static int selinux_binder_set_context_mgr(const struct cred *mgr)
2021{
2022	return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER,
 
 
 
 
2023			    BINDER__SET_CONTEXT_MGR, NULL);
2024}
2025
2026static int selinux_binder_transaction(const struct cred *from,
2027				      const struct cred *to)
2028{
2029	u32 mysid = current_sid();
2030	u32 fromsid = cred_sid(from);
2031	u32 tosid = cred_sid(to);
2032	int rc;
2033
2034	if (mysid != fromsid) {
2035		rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
 
2036				  BINDER__IMPERSONATE, NULL);
2037		if (rc)
2038			return rc;
2039	}
2040
2041	return avc_has_perm(fromsid, tosid,
2042			    SECCLASS_BINDER, BINDER__CALL, NULL);
 
2043}
2044
2045static int selinux_binder_transfer_binder(const struct cred *from,
2046					  const struct cred *to)
2047{
2048	return avc_has_perm(cred_sid(from), cred_sid(to),
2049			    SECCLASS_BINDER, BINDER__TRANSFER,
 
 
 
2050			    NULL);
2051}
2052
2053static int selinux_binder_transfer_file(const struct cred *from,
2054					const struct cred *to,
2055					const struct file *file)
2056{
2057	u32 sid = cred_sid(to);
2058	struct file_security_struct *fsec = selinux_file(file);
2059	struct dentry *dentry = file->f_path.dentry;
2060	struct inode_security_struct *isec;
2061	struct common_audit_data ad;
2062	int rc;
2063
2064	ad.type = LSM_AUDIT_DATA_PATH;
2065	ad.u.path = file->f_path;
2066
2067	if (sid != fsec->sid) {
2068		rc = avc_has_perm(sid, fsec->sid,
 
2069				  SECCLASS_FD,
2070				  FD__USE,
2071				  &ad);
2072		if (rc)
2073			return rc;
2074	}
2075
2076#ifdef CONFIG_BPF_SYSCALL
2077	rc = bpf_fd_pass(file, sid);
2078	if (rc)
2079		return rc;
2080#endif
2081
2082	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2083		return 0;
2084
2085	isec = backing_inode_security(dentry);
2086	return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
 
2087			    &ad);
2088}
2089
2090static int selinux_ptrace_access_check(struct task_struct *child,
2091				       unsigned int mode)
2092{
2093	u32 sid = current_sid();
2094	u32 csid = task_sid_obj(child);
2095
2096	if (mode & PTRACE_MODE_READ)
2097		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ,
2098				NULL);
2099
2100	return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE,
2101			NULL);
2102}
2103
2104static int selinux_ptrace_traceme(struct task_struct *parent)
2105{
2106	return avc_has_perm(task_sid_obj(parent), task_sid_obj(current),
2107			    SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
 
2108}
2109
2110static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective,
2111			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
2112{
2113	return avc_has_perm(current_sid(), task_sid_obj(target),
2114			SECCLASS_PROCESS, PROCESS__GETCAP, NULL);
 
2115}
2116
2117static int selinux_capset(struct cred *new, const struct cred *old,
2118			  const kernel_cap_t *effective,
2119			  const kernel_cap_t *inheritable,
2120			  const kernel_cap_t *permitted)
2121{
2122	return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
 
2123			    PROCESS__SETCAP, NULL);
2124}
2125
2126/*
2127 * (This comment used to live with the selinux_task_setuid hook,
2128 * which was removed).
2129 *
2130 * Since setuid only affects the current process, and since the SELinux
2131 * controls are not based on the Linux identity attributes, SELinux does not
2132 * need to control this operation.  However, SELinux does control the use of
2133 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2134 */
2135
2136static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2137			   int cap, unsigned int opts)
2138{
2139	return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2140}
2141
2142static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb)
2143{
2144	const struct cred *cred = current_cred();
2145	int rc = 0;
2146
2147	if (!sb)
2148		return 0;
2149
2150	switch (cmds) {
2151	case Q_SYNC:
2152	case Q_QUOTAON:
2153	case Q_QUOTAOFF:
2154	case Q_SETINFO:
2155	case Q_SETQUOTA:
2156	case Q_XQUOTAOFF:
2157	case Q_XQUOTAON:
2158	case Q_XSETQLIM:
2159		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2160		break;
2161	case Q_GETFMT:
2162	case Q_GETINFO:
2163	case Q_GETQUOTA:
2164	case Q_XGETQUOTA:
2165	case Q_XGETQSTAT:
2166	case Q_XGETQSTATV:
2167	case Q_XGETNEXTQUOTA:
2168		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2169		break;
2170	default:
2171		rc = 0;  /* let the kernel handle invalid cmds */
2172		break;
2173	}
2174	return rc;
2175}
2176
2177static int selinux_quota_on(struct dentry *dentry)
2178{
2179	const struct cred *cred = current_cred();
2180
2181	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2182}
2183
2184static int selinux_syslog(int type)
2185{
2186	switch (type) {
2187	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
2188	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2189		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
 
2190				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2191	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
2192	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
2193	/* Set level of messages printed to console */
2194	case SYSLOG_ACTION_CONSOLE_LEVEL:
2195		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
 
2196				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2197				    NULL);
2198	}
2199	/* All other syslog types */
2200	return avc_has_perm(current_sid(), SECINITSID_KERNEL,
 
2201			    SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2202}
2203
2204/*
2205 * Check that a process has enough memory to allocate a new virtual
2206 * mapping. 0 means there is enough memory for the allocation to
2207 * succeed and -ENOMEM implies there is not.
2208 *
2209 * Do not audit the selinux permission check, as this is applied to all
2210 * processes that allocate mappings.
2211 */
2212static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2213{
2214	int rc, cap_sys_admin = 0;
2215
2216	rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2217				 CAP_OPT_NOAUDIT, true);
2218	if (rc == 0)
2219		cap_sys_admin = 1;
2220
2221	return cap_sys_admin;
2222}
2223
2224/* binprm security operations */
2225
2226static u32 ptrace_parent_sid(void)
2227{
2228	u32 sid = 0;
2229	struct task_struct *tracer;
2230
2231	rcu_read_lock();
2232	tracer = ptrace_parent(current);
2233	if (tracer)
2234		sid = task_sid_obj(tracer);
2235	rcu_read_unlock();
2236
2237	return sid;
2238}
2239
2240static int check_nnp_nosuid(const struct linux_binprm *bprm,
2241			    const struct task_security_struct *old_tsec,
2242			    const struct task_security_struct *new_tsec)
2243{
2244	int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2245	int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2246	int rc;
2247	u32 av;
2248
2249	if (!nnp && !nosuid)
2250		return 0; /* neither NNP nor nosuid */
2251
2252	if (new_tsec->sid == old_tsec->sid)
2253		return 0; /* No change in credentials */
2254
2255	/*
2256	 * If the policy enables the nnp_nosuid_transition policy capability,
2257	 * then we permit transitions under NNP or nosuid if the
2258	 * policy allows the corresponding permission between
2259	 * the old and new contexts.
2260	 */
2261	if (selinux_policycap_nnp_nosuid_transition()) {
2262		av = 0;
2263		if (nnp)
2264			av |= PROCESS2__NNP_TRANSITION;
2265		if (nosuid)
2266			av |= PROCESS2__NOSUID_TRANSITION;
2267		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
 
2268				  SECCLASS_PROCESS2, av, NULL);
2269		if (!rc)
2270			return 0;
2271	}
2272
2273	/*
2274	 * We also permit NNP or nosuid transitions to bounded SIDs,
2275	 * i.e. SIDs that are guaranteed to only be allowed a subset
2276	 * of the permissions of the current SID.
2277	 */
2278	rc = security_bounded_transition(old_tsec->sid,
2279					 new_tsec->sid);
2280	if (!rc)
2281		return 0;
2282
2283	/*
2284	 * On failure, preserve the errno values for NNP vs nosuid.
2285	 * NNP:  Operation not permitted for caller.
2286	 * nosuid:  Permission denied to file.
2287	 */
2288	if (nnp)
2289		return -EPERM;
2290	return -EACCES;
2291}
2292
2293static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2294{
2295	const struct task_security_struct *old_tsec;
2296	struct task_security_struct *new_tsec;
2297	struct inode_security_struct *isec;
2298	struct common_audit_data ad;
2299	struct inode *inode = file_inode(bprm->file);
2300	int rc;
2301
2302	/* SELinux context only depends on initial program or script and not
2303	 * the script interpreter */
2304
2305	old_tsec = selinux_cred(current_cred());
2306	new_tsec = selinux_cred(bprm->cred);
2307	isec = inode_security(inode);
2308
2309	/* Default to the current task SID. */
2310	new_tsec->sid = old_tsec->sid;
2311	new_tsec->osid = old_tsec->sid;
2312
2313	/* Reset fs, key, and sock SIDs on execve. */
2314	new_tsec->create_sid = 0;
2315	new_tsec->keycreate_sid = 0;
2316	new_tsec->sockcreate_sid = 0;
2317
2318	/*
2319	 * Before policy is loaded, label any task outside kernel space
2320	 * as SECINITSID_INIT, so that any userspace tasks surviving from
2321	 * early boot end up with a label different from SECINITSID_KERNEL
2322	 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
2323	 */
2324	if (!selinux_initialized()) {
2325		new_tsec->sid = SECINITSID_INIT;
2326		/* also clear the exec_sid just in case */
2327		new_tsec->exec_sid = 0;
2328		return 0;
2329	}
2330
2331	if (old_tsec->exec_sid) {
2332		new_tsec->sid = old_tsec->exec_sid;
2333		/* Reset exec SID on execve. */
2334		new_tsec->exec_sid = 0;
2335
2336		/* Fail on NNP or nosuid if not an allowed transition. */
2337		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2338		if (rc)
2339			return rc;
2340	} else {
2341		/* Check for a default transition on this program. */
2342		rc = security_transition_sid(old_tsec->sid,
2343					     isec->sid, SECCLASS_PROCESS, NULL,
2344					     &new_tsec->sid);
2345		if (rc)
2346			return rc;
2347
2348		/*
2349		 * Fallback to old SID on NNP or nosuid if not an allowed
2350		 * transition.
2351		 */
2352		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2353		if (rc)
2354			new_tsec->sid = old_tsec->sid;
2355	}
2356
2357	ad.type = LSM_AUDIT_DATA_FILE;
2358	ad.u.file = bprm->file;
2359
2360	if (new_tsec->sid == old_tsec->sid) {
2361		rc = avc_has_perm(old_tsec->sid, isec->sid,
 
2362				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2363		if (rc)
2364			return rc;
2365	} else {
2366		/* Check permissions for the transition. */
2367		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
 
2368				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2369		if (rc)
2370			return rc;
2371
2372		rc = avc_has_perm(new_tsec->sid, isec->sid,
 
2373				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2374		if (rc)
2375			return rc;
2376
2377		/* Check for shared state */
2378		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2379			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
 
2380					  SECCLASS_PROCESS, PROCESS__SHARE,
2381					  NULL);
2382			if (rc)
2383				return -EPERM;
2384		}
2385
2386		/* Make sure that anyone attempting to ptrace over a task that
2387		 * changes its SID has the appropriate permit */
2388		if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2389			u32 ptsid = ptrace_parent_sid();
2390			if (ptsid != 0) {
2391				rc = avc_has_perm(ptsid, new_tsec->sid,
 
2392						  SECCLASS_PROCESS,
2393						  PROCESS__PTRACE, NULL);
2394				if (rc)
2395					return -EPERM;
2396			}
2397		}
2398
2399		/* Clear any possibly unsafe personality bits on exec: */
2400		bprm->per_clear |= PER_CLEAR_ON_SETID;
2401
2402		/* Enable secure mode for SIDs transitions unless
2403		   the noatsecure permission is granted between
2404		   the two SIDs, i.e. ahp returns 0. */
2405		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
 
2406				  SECCLASS_PROCESS, PROCESS__NOATSECURE,
2407				  NULL);
2408		bprm->secureexec |= !!rc;
2409	}
2410
2411	return 0;
2412}
2413
2414static int match_file(const void *p, struct file *file, unsigned fd)
2415{
2416	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2417}
2418
2419/* Derived from fs/exec.c:flush_old_files. */
2420static inline void flush_unauthorized_files(const struct cred *cred,
2421					    struct files_struct *files)
2422{
2423	struct file *file, *devnull = NULL;
2424	struct tty_struct *tty;
2425	int drop_tty = 0;
2426	unsigned n;
2427
2428	tty = get_current_tty();
2429	if (tty) {
2430		spin_lock(&tty->files_lock);
2431		if (!list_empty(&tty->tty_files)) {
2432			struct tty_file_private *file_priv;
2433
2434			/* Revalidate access to controlling tty.
2435			   Use file_path_has_perm on the tty path directly
2436			   rather than using file_has_perm, as this particular
2437			   open file may belong to another process and we are
2438			   only interested in the inode-based check here. */
2439			file_priv = list_first_entry(&tty->tty_files,
2440						struct tty_file_private, list);
2441			file = file_priv->file;
2442			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2443				drop_tty = 1;
2444		}
2445		spin_unlock(&tty->files_lock);
2446		tty_kref_put(tty);
2447	}
2448	/* Reset controlling tty. */
2449	if (drop_tty)
2450		no_tty();
2451
2452	/* Revalidate access to inherited open files. */
2453	n = iterate_fd(files, 0, match_file, cred);
2454	if (!n) /* none found? */
2455		return;
2456
2457	devnull = dentry_open(&selinux_null, O_RDWR, cred);
2458	if (IS_ERR(devnull))
2459		devnull = NULL;
2460	/* replace all the matching ones with this */
2461	do {
2462		replace_fd(n - 1, devnull, 0);
2463	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2464	if (devnull)
2465		fput(devnull);
2466}
2467
2468/*
2469 * Prepare a process for imminent new credential changes due to exec
2470 */
2471static void selinux_bprm_committing_creds(const struct linux_binprm *bprm)
2472{
2473	struct task_security_struct *new_tsec;
2474	struct rlimit *rlim, *initrlim;
2475	int rc, i;
2476
2477	new_tsec = selinux_cred(bprm->cred);
2478	if (new_tsec->sid == new_tsec->osid)
2479		return;
2480
2481	/* Close files for which the new task SID is not authorized. */
2482	flush_unauthorized_files(bprm->cred, current->files);
2483
2484	/* Always clear parent death signal on SID transitions. */
2485	current->pdeath_signal = 0;
2486
2487	/* Check whether the new SID can inherit resource limits from the old
2488	 * SID.  If not, reset all soft limits to the lower of the current
2489	 * task's hard limit and the init task's soft limit.
2490	 *
2491	 * Note that the setting of hard limits (even to lower them) can be
2492	 * controlled by the setrlimit check.  The inclusion of the init task's
2493	 * soft limit into the computation is to avoid resetting soft limits
2494	 * higher than the default soft limit for cases where the default is
2495	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2496	 */
2497	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
 
2498			  PROCESS__RLIMITINH, NULL);
2499	if (rc) {
2500		/* protect against do_prlimit() */
2501		task_lock(current);
2502		for (i = 0; i < RLIM_NLIMITS; i++) {
2503			rlim = current->signal->rlim + i;
2504			initrlim = init_task.signal->rlim + i;
2505			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2506		}
2507		task_unlock(current);
2508		if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2509			update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2510	}
2511}
2512
2513/*
2514 * Clean up the process immediately after the installation of new credentials
2515 * due to exec
2516 */
2517static void selinux_bprm_committed_creds(const struct linux_binprm *bprm)
2518{
2519	const struct task_security_struct *tsec = selinux_cred(current_cred());
2520	u32 osid, sid;
2521	int rc;
2522
2523	osid = tsec->osid;
2524	sid = tsec->sid;
2525
2526	if (sid == osid)
2527		return;
2528
2529	/* Check whether the new SID can inherit signal state from the old SID.
2530	 * If not, clear itimers to avoid subsequent signal generation and
2531	 * flush and unblock signals.
2532	 *
2533	 * This must occur _after_ the task SID has been updated so that any
2534	 * kill done after the flush will be checked against the new SID.
2535	 */
2536	rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
 
2537	if (rc) {
2538		clear_itimer();
2539
2540		spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2541		if (!fatal_signal_pending(current)) {
2542			flush_sigqueue(&current->pending);
2543			flush_sigqueue(&current->signal->shared_pending);
2544			flush_signal_handlers(current, 1);
2545			sigemptyset(&current->blocked);
2546			recalc_sigpending();
2547		}
2548		spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2549	}
2550
2551	/* Wake up the parent if it is waiting so that it can recheck
2552	 * wait permission to the new task SID. */
2553	read_lock(&tasklist_lock);
2554	__wake_up_parent(current, unrcu_pointer(current->real_parent));
2555	read_unlock(&tasklist_lock);
2556}
2557
2558/* superblock security operations */
2559
2560static int selinux_sb_alloc_security(struct super_block *sb)
2561{
2562	struct superblock_security_struct *sbsec = selinux_superblock(sb);
 
 
 
 
2563
2564	mutex_init(&sbsec->lock);
2565	INIT_LIST_HEAD(&sbsec->isec_head);
2566	spin_lock_init(&sbsec->isec_lock);
 
2567	sbsec->sid = SECINITSID_UNLABELED;
2568	sbsec->def_sid = SECINITSID_FILE;
2569	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 
2570
2571	return 0;
2572}
2573
 
 
 
 
 
2574static inline int opt_len(const char *s)
2575{
2576	bool open_quote = false;
2577	int len;
2578	char c;
2579
2580	for (len = 0; (c = s[len]) != '\0'; len++) {
2581		if (c == '"')
2582			open_quote = !open_quote;
2583		if (c == ',' && !open_quote)
2584			break;
2585	}
2586	return len;
2587}
2588
2589static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2590{
2591	char *from = options;
2592	char *to = options;
2593	bool first = true;
2594	int rc;
2595
2596	while (1) {
2597		int len = opt_len(from);
2598		int token;
2599		char *arg = NULL;
2600
2601		token = match_opt_prefix(from, len, &arg);
2602
2603		if (token != Opt_error) {
2604			char *p, *q;
2605
2606			/* strip quotes */
2607			if (arg) {
2608				for (p = q = arg; p < from + len; p++) {
2609					char c = *p;
2610					if (c != '"')
2611						*q++ = c;
2612				}
2613				arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2614				if (!arg) {
2615					rc = -ENOMEM;
2616					goto free_opt;
2617				}
2618			}
2619			rc = selinux_add_opt(token, arg, mnt_opts);
2620			kfree(arg);
2621			arg = NULL;
2622			if (unlikely(rc)) {
 
2623				goto free_opt;
2624			}
2625		} else {
2626			if (!first) {	// copy with preceding comma
2627				from--;
2628				len++;
2629			}
2630			if (to != from)
2631				memmove(to, from, len);
2632			to += len;
2633			first = false;
2634		}
2635		if (!from[len])
2636			break;
2637		from += len + 1;
2638	}
2639	*to = '\0';
2640	return 0;
2641
2642free_opt:
2643	if (*mnt_opts) {
2644		selinux_free_mnt_opts(*mnt_opts);
2645		*mnt_opts = NULL;
2646	}
2647	return rc;
2648}
2649
2650static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2651{
2652	struct selinux_mnt_opts *opts = mnt_opts;
2653	struct superblock_security_struct *sbsec = selinux_superblock(sb);
2654
2655	/*
2656	 * Superblock not initialized (i.e. no options) - reject if any
2657	 * options specified, otherwise accept.
2658	 */
2659	if (!(sbsec->flags & SE_SBINITIALIZED))
2660		return opts ? 1 : 0;
2661
2662	/*
2663	 * Superblock initialized and no options specified - reject if
2664	 * superblock has any options set, otherwise accept.
2665	 */
2666	if (!opts)
2667		return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2668
2669	if (opts->fscontext_sid) {
2670		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2671			       opts->fscontext_sid))
2672			return 1;
2673	}
2674	if (opts->context_sid) {
2675		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2676			       opts->context_sid))
2677			return 1;
2678	}
2679	if (opts->rootcontext_sid) {
2680		struct inode_security_struct *root_isec;
2681
2682		root_isec = backing_inode_security(sb->s_root);
2683		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2684			       opts->rootcontext_sid))
2685			return 1;
2686	}
2687	if (opts->defcontext_sid) {
2688		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2689			       opts->defcontext_sid))
2690			return 1;
2691	}
2692	return 0;
2693}
2694
2695static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2696{
2697	struct selinux_mnt_opts *opts = mnt_opts;
2698	struct superblock_security_struct *sbsec = selinux_superblock(sb);
 
 
2699
2700	if (!(sbsec->flags & SE_SBINITIALIZED))
2701		return 0;
2702
2703	if (!opts)
2704		return 0;
2705
2706	if (opts->fscontext_sid) {
2707		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2708			       opts->fscontext_sid))
 
 
2709			goto out_bad_option;
2710	}
2711	if (opts->context_sid) {
2712		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2713			       opts->context_sid))
 
 
2714			goto out_bad_option;
2715	}
2716	if (opts->rootcontext_sid) {
2717		struct inode_security_struct *root_isec;
2718		root_isec = backing_inode_security(sb->s_root);
2719		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2720			       opts->rootcontext_sid))
 
 
2721			goto out_bad_option;
2722	}
2723	if (opts->defcontext_sid) {
2724		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2725			       opts->defcontext_sid))
 
 
2726			goto out_bad_option;
2727	}
2728	return 0;
2729
2730out_bad_option:
2731	pr_warn("SELinux: unable to change security options "
2732	       "during remount (dev %s, type=%s)\n", sb->s_id,
2733	       sb->s_type->name);
2734	return -EINVAL;
2735}
2736
2737static int selinux_sb_kern_mount(const struct super_block *sb)
2738{
2739	const struct cred *cred = current_cred();
2740	struct common_audit_data ad;
2741
2742	ad.type = LSM_AUDIT_DATA_DENTRY;
2743	ad.u.dentry = sb->s_root;
2744	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2745}
2746
2747static int selinux_sb_statfs(struct dentry *dentry)
2748{
2749	const struct cred *cred = current_cred();
2750	struct common_audit_data ad;
2751
2752	ad.type = LSM_AUDIT_DATA_DENTRY;
2753	ad.u.dentry = dentry->d_sb->s_root;
2754	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2755}
2756
2757static int selinux_mount(const char *dev_name,
2758			 const struct path *path,
2759			 const char *type,
2760			 unsigned long flags,
2761			 void *data)
2762{
2763	const struct cred *cred = current_cred();
2764
2765	if (flags & MS_REMOUNT)
2766		return superblock_has_perm(cred, path->dentry->d_sb,
2767					   FILESYSTEM__REMOUNT, NULL);
2768	else
2769		return path_has_perm(cred, path, FILE__MOUNTON);
2770}
2771
2772static int selinux_move_mount(const struct path *from_path,
2773			      const struct path *to_path)
2774{
2775	const struct cred *cred = current_cred();
2776
2777	return path_has_perm(cred, to_path, FILE__MOUNTON);
2778}
2779
2780static int selinux_umount(struct vfsmount *mnt, int flags)
2781{
2782	const struct cred *cred = current_cred();
2783
2784	return superblock_has_perm(cred, mnt->mnt_sb,
2785				   FILESYSTEM__UNMOUNT, NULL);
2786}
2787
2788static int selinux_fs_context_submount(struct fs_context *fc,
2789				   struct super_block *reference)
2790{
2791	const struct superblock_security_struct *sbsec = selinux_superblock(reference);
2792	struct selinux_mnt_opts *opts;
2793
2794	/*
2795	 * Ensure that fc->security remains NULL when no options are set
2796	 * as expected by selinux_set_mnt_opts().
2797	 */
2798	if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT)))
2799		return 0;
2800
2801	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2802	if (!opts)
2803		return -ENOMEM;
2804
2805	if (sbsec->flags & FSCONTEXT_MNT)
2806		opts->fscontext_sid = sbsec->sid;
2807	if (sbsec->flags & CONTEXT_MNT)
2808		opts->context_sid = sbsec->mntpoint_sid;
2809	if (sbsec->flags & DEFCONTEXT_MNT)
2810		opts->defcontext_sid = sbsec->def_sid;
2811	fc->security = opts;
2812	return 0;
2813}
2814
2815static int selinux_fs_context_dup(struct fs_context *fc,
2816				  struct fs_context *src_fc)
2817{
2818	const struct selinux_mnt_opts *src = src_fc->security;
 
2819
2820	if (!src)
2821		return 0;
2822
2823	fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2824	return fc->security ? 0 : -ENOMEM;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2825}
2826
2827static const struct fs_parameter_spec selinux_fs_parameters[] = {
2828	fsparam_string(CONTEXT_STR,	Opt_context),
2829	fsparam_string(DEFCONTEXT_STR,	Opt_defcontext),
2830	fsparam_string(FSCONTEXT_STR,	Opt_fscontext),
2831	fsparam_string(ROOTCONTEXT_STR,	Opt_rootcontext),
2832	fsparam_flag  (SECLABEL_STR,	Opt_seclabel),
2833	{}
2834};
2835
2836static int selinux_fs_context_parse_param(struct fs_context *fc,
2837					  struct fs_parameter *param)
2838{
2839	struct fs_parse_result result;
2840	int opt;
2841
2842	opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2843	if (opt < 0)
2844		return opt;
2845
2846	return selinux_add_opt(opt, param->string, &fc->security);
 
 
 
 
 
2847}
2848
2849/* inode security operations */
2850
2851static int selinux_inode_alloc_security(struct inode *inode)
2852{
2853	struct inode_security_struct *isec = selinux_inode(inode);
2854	u32 sid = current_sid();
2855
2856	spin_lock_init(&isec->lock);
2857	INIT_LIST_HEAD(&isec->list);
2858	isec->inode = inode;
2859	isec->sid = SECINITSID_UNLABELED;
2860	isec->sclass = SECCLASS_FILE;
2861	isec->task_sid = sid;
2862	isec->initialized = LABEL_INVALID;
2863
2864	return 0;
2865}
2866
2867static void selinux_inode_free_security(struct inode *inode)
2868{
2869	inode_free_security(inode);
2870}
2871
2872static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2873					const struct qstr *name,
2874					const char **xattr_name, void **ctx,
2875					u32 *ctxlen)
2876{
2877	u32 newsid;
2878	int rc;
2879
2880	rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2881					   d_inode(dentry->d_parent), name,
2882					   inode_mode_to_security_class(mode),
2883					   &newsid);
2884	if (rc)
2885		return rc;
2886
2887	if (xattr_name)
2888		*xattr_name = XATTR_NAME_SELINUX;
2889
2890	return security_sid_to_context(newsid, (char **)ctx,
2891				       ctxlen);
2892}
2893
2894static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2895					  struct qstr *name,
2896					  const struct cred *old,
2897					  struct cred *new)
2898{
2899	u32 newsid;
2900	int rc;
2901	struct task_security_struct *tsec;
2902
2903	rc = selinux_determine_inode_label(selinux_cred(old),
2904					   d_inode(dentry->d_parent), name,
2905					   inode_mode_to_security_class(mode),
2906					   &newsid);
2907	if (rc)
2908		return rc;
2909
2910	tsec = selinux_cred(new);
2911	tsec->create_sid = newsid;
2912	return 0;
2913}
2914
2915static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2916				       const struct qstr *qstr,
2917				       struct xattr *xattrs, int *xattr_count)
 
2918{
2919	const struct task_security_struct *tsec = selinux_cred(current_cred());
2920	struct superblock_security_struct *sbsec;
2921	struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
2922	u32 newsid, clen;
2923	int rc;
2924	char *context;
2925
2926	sbsec = selinux_superblock(dir->i_sb);
2927
2928	newsid = tsec->create_sid;
2929
2930	rc = selinux_determine_inode_label(tsec, dir, qstr,
2931		inode_mode_to_security_class(inode->i_mode),
2932		&newsid);
2933	if (rc)
2934		return rc;
2935
2936	/* Possibly defer initialization to selinux_complete_init. */
2937	if (sbsec->flags & SE_SBINITIALIZED) {
2938		struct inode_security_struct *isec = selinux_inode(inode);
2939		isec->sclass = inode_mode_to_security_class(inode->i_mode);
2940		isec->sid = newsid;
2941		isec->initialized = LABEL_INITIALIZED;
2942	}
2943
2944	if (!selinux_initialized() ||
2945	    !(sbsec->flags & SBLABEL_MNT))
2946		return -EOPNOTSUPP;
2947
2948	if (xattr) {
2949		rc = security_sid_to_context_force(newsid,
 
 
 
2950						   &context, &clen);
2951		if (rc)
2952			return rc;
2953		xattr->value = context;
2954		xattr->value_len = clen;
2955		xattr->name = XATTR_SELINUX_SUFFIX;
2956	}
2957
2958	return 0;
2959}
2960
2961static int selinux_inode_init_security_anon(struct inode *inode,
2962					    const struct qstr *name,
2963					    const struct inode *context_inode)
2964{
2965	const struct task_security_struct *tsec = selinux_cred(current_cred());
2966	struct common_audit_data ad;
2967	struct inode_security_struct *isec;
2968	int rc;
2969
2970	if (unlikely(!selinux_initialized()))
2971		return 0;
2972
2973	isec = selinux_inode(inode);
2974
2975	/*
2976	 * We only get here once per ephemeral inode.  The inode has
2977	 * been initialized via inode_alloc_security but is otherwise
2978	 * untouched.
2979	 */
2980
2981	if (context_inode) {
2982		struct inode_security_struct *context_isec =
2983			selinux_inode(context_inode);
2984		if (context_isec->initialized != LABEL_INITIALIZED) {
2985			pr_err("SELinux:  context_inode is not initialized\n");
2986			return -EACCES;
2987		}
2988
2989		isec->sclass = context_isec->sclass;
2990		isec->sid = context_isec->sid;
2991	} else {
2992		isec->sclass = SECCLASS_ANON_INODE;
2993		rc = security_transition_sid(
2994			tsec->sid, tsec->sid,
2995			isec->sclass, name, &isec->sid);
2996		if (rc)
2997			return rc;
2998	}
2999
3000	isec->initialized = LABEL_INITIALIZED;
3001	/*
3002	 * Now that we've initialized security, check whether we're
3003	 * allowed to actually create this type of anonymous inode.
3004	 */
3005
3006	ad.type = LSM_AUDIT_DATA_ANONINODE;
3007	ad.u.anonclass = name ? (const char *)name->name : "?";
3008
3009	return avc_has_perm(tsec->sid,
3010			    isec->sid,
3011			    isec->sclass,
3012			    FILE__CREATE,
3013			    &ad);
3014}
3015
3016static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3017{
3018	return may_create(dir, dentry, SECCLASS_FILE);
3019}
3020
3021static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3022{
3023	return may_link(dir, old_dentry, MAY_LINK);
3024}
3025
3026static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3027{
3028	return may_link(dir, dentry, MAY_UNLINK);
3029}
3030
3031static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3032{
3033	return may_create(dir, dentry, SECCLASS_LNK_FILE);
3034}
3035
3036static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3037{
3038	return may_create(dir, dentry, SECCLASS_DIR);
3039}
3040
3041static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3042{
3043	return may_link(dir, dentry, MAY_RMDIR);
3044}
3045
3046static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3047{
3048	return may_create(dir, dentry, inode_mode_to_security_class(mode));
3049}
3050
3051static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3052				struct inode *new_inode, struct dentry *new_dentry)
3053{
3054	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3055}
3056
3057static int selinux_inode_readlink(struct dentry *dentry)
3058{
3059	const struct cred *cred = current_cred();
3060
3061	return dentry_has_perm(cred, dentry, FILE__READ);
3062}
3063
3064static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3065				     bool rcu)
3066{
3067	const struct cred *cred = current_cred();
3068	struct common_audit_data ad;
3069	struct inode_security_struct *isec;
3070	u32 sid;
3071
 
 
3072	ad.type = LSM_AUDIT_DATA_DENTRY;
3073	ad.u.dentry = dentry;
3074	sid = cred_sid(cred);
3075	isec = inode_security_rcu(inode, rcu);
3076	if (IS_ERR(isec))
3077		return PTR_ERR(isec);
3078
3079	return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
 
 
3080}
3081
3082static noinline int audit_inode_permission(struct inode *inode,
3083					   u32 perms, u32 audited, u32 denied,
3084					   int result)
3085{
3086	struct common_audit_data ad;
3087	struct inode_security_struct *isec = selinux_inode(inode);
 
3088
3089	ad.type = LSM_AUDIT_DATA_INODE;
3090	ad.u.inode = inode;
3091
3092	return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
 
3093			    audited, denied, result, &ad);
 
 
 
3094}
3095
3096static int selinux_inode_permission(struct inode *inode, int mask)
3097{
3098	const struct cred *cred = current_cred();
3099	u32 perms;
3100	bool from_access;
3101	bool no_block = mask & MAY_NOT_BLOCK;
3102	struct inode_security_struct *isec;
3103	u32 sid;
3104	struct av_decision avd;
3105	int rc, rc2;
3106	u32 audited, denied;
3107
3108	from_access = mask & MAY_ACCESS;
3109	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3110
3111	/* No permission to check.  Existence test. */
3112	if (!mask)
3113		return 0;
3114
 
 
3115	if (unlikely(IS_PRIVATE(inode)))
3116		return 0;
3117
3118	perms = file_mask_to_av(inode->i_mode, mask);
3119
3120	sid = cred_sid(cred);
3121	isec = inode_security_rcu(inode, no_block);
3122	if (IS_ERR(isec))
3123		return PTR_ERR(isec);
3124
3125	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
 
 
3126				  &avd);
3127	audited = avc_audit_required(perms, &avd, rc,
3128				     from_access ? FILE__AUDIT_ACCESS : 0,
3129				     &denied);
3130	if (likely(!audited))
3131		return rc;
3132
 
 
 
 
3133	rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3134	if (rc2)
3135		return rc2;
3136	return rc;
3137}
3138
3139static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3140{
3141	const struct cred *cred = current_cred();
3142	struct inode *inode = d_backing_inode(dentry);
3143	unsigned int ia_valid = iattr->ia_valid;
3144	__u32 av = FILE__WRITE;
3145
3146	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3147	if (ia_valid & ATTR_FORCE) {
3148		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3149			      ATTR_FORCE);
3150		if (!ia_valid)
3151			return 0;
3152	}
3153
3154	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3155			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3156		return dentry_has_perm(cred, dentry, FILE__SETATTR);
3157
3158	if (selinux_policycap_openperm() &&
3159	    inode->i_sb->s_magic != SOCKFS_MAGIC &&
3160	    (ia_valid & ATTR_SIZE) &&
3161	    !(ia_valid & ATTR_FILE))
3162		av |= FILE__OPEN;
3163
3164	return dentry_has_perm(cred, dentry, av);
3165}
3166
3167static int selinux_inode_getattr(const struct path *path)
3168{
3169	return path_has_perm(current_cred(), path, FILE__GETATTR);
3170}
3171
3172static bool has_cap_mac_admin(bool audit)
3173{
3174	const struct cred *cred = current_cred();
3175	unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3176
3177	if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3178		return false;
3179	if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3180		return false;
3181	return true;
3182}
3183
3184static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3185				  struct dentry *dentry, const char *name,
3186				  const void *value, size_t size, int flags)
3187{
3188	struct inode *inode = d_backing_inode(dentry);
3189	struct inode_security_struct *isec;
3190	struct superblock_security_struct *sbsec;
3191	struct common_audit_data ad;
3192	u32 newsid, sid = current_sid();
3193	int rc = 0;
3194
3195	if (strcmp(name, XATTR_NAME_SELINUX)) {
3196		rc = cap_inode_setxattr(dentry, name, value, size, flags);
3197		if (rc)
3198			return rc;
3199
3200		/* Not an attribute we recognize, so just check the
3201		   ordinary setattr permission. */
3202		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3203	}
3204
3205	if (!selinux_initialized())
3206		return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3207
3208	sbsec = selinux_superblock(inode->i_sb);
3209	if (!(sbsec->flags & SBLABEL_MNT))
3210		return -EOPNOTSUPP;
3211
3212	if (!inode_owner_or_capable(idmap, inode))
3213		return -EPERM;
3214
3215	ad.type = LSM_AUDIT_DATA_DENTRY;
3216	ad.u.dentry = dentry;
3217
3218	isec = backing_inode_security(dentry);
3219	rc = avc_has_perm(sid, isec->sid, isec->sclass,
 
3220			  FILE__RELABELFROM, &ad);
3221	if (rc)
3222		return rc;
3223
3224	rc = security_context_to_sid(value, size, &newsid,
3225				     GFP_KERNEL);
3226	if (rc == -EINVAL) {
3227		if (!has_cap_mac_admin(true)) {
3228			struct audit_buffer *ab;
3229			size_t audit_size;
3230
3231			/* We strip a nul only if it is at the end, otherwise the
3232			 * context contains a nul and we should audit that */
3233			if (value) {
3234				const char *str = value;
3235
3236				if (str[size - 1] == '\0')
3237					audit_size = size - 1;
3238				else
3239					audit_size = size;
3240			} else {
3241				audit_size = 0;
3242			}
3243			ab = audit_log_start(audit_context(),
3244					     GFP_ATOMIC, AUDIT_SELINUX_ERR);
3245			if (!ab)
3246				return rc;
3247			audit_log_format(ab, "op=setxattr invalid_context=");
3248			audit_log_n_untrustedstring(ab, value, audit_size);
3249			audit_log_end(ab);
3250
3251			return rc;
3252		}
3253		rc = security_context_to_sid_force(value,
3254						   size, &newsid);
3255	}
3256	if (rc)
3257		return rc;
3258
3259	rc = avc_has_perm(sid, newsid, isec->sclass,
 
3260			  FILE__RELABELTO, &ad);
3261	if (rc)
3262		return rc;
3263
3264	rc = security_validate_transition(isec->sid, newsid,
3265					  sid, isec->sclass);
3266	if (rc)
3267		return rc;
3268
3269	return avc_has_perm(newsid,
 
3270			    sbsec->sid,
3271			    SECCLASS_FILESYSTEM,
3272			    FILESYSTEM__ASSOCIATE,
3273			    &ad);
3274}
3275
3276static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3277				 struct dentry *dentry, const char *acl_name,
3278				 struct posix_acl *kacl)
3279{
3280	return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3281}
3282
3283static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3284				 struct dentry *dentry, const char *acl_name)
3285{
3286	return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3287}
3288
3289static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3290				    struct dentry *dentry, const char *acl_name)
3291{
3292	return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3293}
3294
3295static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3296					const void *value, size_t size,
3297					int flags)
3298{
3299	struct inode *inode = d_backing_inode(dentry);
3300	struct inode_security_struct *isec;
3301	u32 newsid;
3302	int rc;
3303
3304	if (strcmp(name, XATTR_NAME_SELINUX)) {
3305		/* Not an attribute we recognize, so nothing to do. */
3306		return;
3307	}
3308
3309	if (!selinux_initialized()) {
3310		/* If we haven't even been initialized, then we can't validate
3311		 * against a policy, so leave the label as invalid. It may
3312		 * resolve to a valid label on the next revalidation try if
3313		 * we've since initialized.
3314		 */
3315		return;
3316	}
3317
3318	rc = security_context_to_sid_force(value, size,
3319					   &newsid);
3320	if (rc) {
3321		pr_err("SELinux:  unable to map context to SID"
3322		       "for (%s, %lu), rc=%d\n",
3323		       inode->i_sb->s_id, inode->i_ino, -rc);
3324		return;
3325	}
3326
3327	isec = backing_inode_security(dentry);
3328	spin_lock(&isec->lock);
3329	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3330	isec->sid = newsid;
3331	isec->initialized = LABEL_INITIALIZED;
3332	spin_unlock(&isec->lock);
 
 
3333}
3334
3335static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3336{
3337	const struct cred *cred = current_cred();
3338
3339	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3340}
3341
3342static int selinux_inode_listxattr(struct dentry *dentry)
3343{
3344	const struct cred *cred = current_cred();
3345
3346	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3347}
3348
3349static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3350				     struct dentry *dentry, const char *name)
3351{
3352	if (strcmp(name, XATTR_NAME_SELINUX)) {
3353		int rc = cap_inode_removexattr(idmap, dentry, name);
3354		if (rc)
3355			return rc;
3356
3357		/* Not an attribute we recognize, so just check the
3358		   ordinary setattr permission. */
3359		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3360	}
3361
3362	if (!selinux_initialized())
3363		return 0;
3364
3365	/* No one is allowed to remove a SELinux security label.
3366	   You can change the label, but all data must be labeled. */
3367	return -EACCES;
3368}
3369
3370static int selinux_path_notify(const struct path *path, u64 mask,
3371						unsigned int obj_type)
3372{
3373	int ret;
3374	u32 perm;
3375
3376	struct common_audit_data ad;
3377
3378	ad.type = LSM_AUDIT_DATA_PATH;
3379	ad.u.path = *path;
3380
3381	/*
3382	 * Set permission needed based on the type of mark being set.
3383	 * Performs an additional check for sb watches.
3384	 */
3385	switch (obj_type) {
3386	case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3387		perm = FILE__WATCH_MOUNT;
3388		break;
3389	case FSNOTIFY_OBJ_TYPE_SB:
3390		perm = FILE__WATCH_SB;
3391		ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3392						FILESYSTEM__WATCH, &ad);
3393		if (ret)
3394			return ret;
3395		break;
3396	case FSNOTIFY_OBJ_TYPE_INODE:
3397		perm = FILE__WATCH;
3398		break;
3399	default:
3400		return -EINVAL;
3401	}
3402
3403	/* blocking watches require the file:watch_with_perm permission */
3404	if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3405		perm |= FILE__WATCH_WITH_PERM;
3406
3407	/* watches on read-like events need the file:watch_reads permission */
3408	if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3409		perm |= FILE__WATCH_READS;
3410
3411	return path_has_perm(current_cred(), path, perm);
3412}
3413
3414/*
3415 * Copy the inode security context value to the user.
3416 *
3417 * Permission check is handled by selinux_inode_getxattr hook.
3418 */
3419static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3420				     struct inode *inode, const char *name,
3421				     void **buffer, bool alloc)
3422{
3423	u32 size;
3424	int error;
3425	char *context = NULL;
3426	struct inode_security_struct *isec;
3427
3428	/*
3429	 * If we're not initialized yet, then we can't validate contexts, so
3430	 * just let vfs_getxattr fall back to using the on-disk xattr.
3431	 */
3432	if (!selinux_initialized() ||
3433	    strcmp(name, XATTR_SELINUX_SUFFIX))
3434		return -EOPNOTSUPP;
3435
3436	/*
3437	 * If the caller has CAP_MAC_ADMIN, then get the raw context
3438	 * value even if it is not defined by current policy; otherwise,
3439	 * use the in-core value under current policy.
3440	 * Use the non-auditing forms of the permission checks since
3441	 * getxattr may be called by unprivileged processes commonly
3442	 * and lack of permission just means that we fall back to the
3443	 * in-core context value, not a denial.
3444	 */
3445	isec = inode_security(inode);
3446	if (has_cap_mac_admin(false))
3447		error = security_sid_to_context_force(isec->sid, &context,
 
3448						      &size);
3449	else
3450		error = security_sid_to_context(isec->sid,
3451						&context, &size);
3452	if (error)
3453		return error;
3454	error = size;
3455	if (alloc) {
3456		*buffer = context;
3457		goto out_nofree;
3458	}
3459	kfree(context);
3460out_nofree:
3461	return error;
3462}
3463
3464static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3465				     const void *value, size_t size, int flags)
3466{
3467	struct inode_security_struct *isec = inode_security_novalidate(inode);
3468	struct superblock_security_struct *sbsec;
3469	u32 newsid;
3470	int rc;
3471
3472	if (strcmp(name, XATTR_SELINUX_SUFFIX))
3473		return -EOPNOTSUPP;
3474
3475	sbsec = selinux_superblock(inode->i_sb);
3476	if (!(sbsec->flags & SBLABEL_MNT))
3477		return -EOPNOTSUPP;
3478
3479	if (!value || !size)
3480		return -EACCES;
3481
3482	rc = security_context_to_sid(value, size, &newsid,
3483				     GFP_KERNEL);
3484	if (rc)
3485		return rc;
3486
3487	spin_lock(&isec->lock);
3488	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3489	isec->sid = newsid;
3490	isec->initialized = LABEL_INITIALIZED;
3491	spin_unlock(&isec->lock);
3492	return 0;
3493}
3494
3495static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3496{
3497	const int len = sizeof(XATTR_NAME_SELINUX);
3498
3499	if (!selinux_initialized())
3500		return 0;
3501
3502	if (buffer && len <= buffer_size)
3503		memcpy(buffer, XATTR_NAME_SELINUX, len);
3504	return len;
3505}
3506
3507static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3508{
3509	struct inode_security_struct *isec = inode_security_novalidate(inode);
3510	*secid = isec->sid;
3511}
3512
3513static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3514{
3515	u32 sid;
3516	struct task_security_struct *tsec;
3517	struct cred *new_creds = *new;
3518
3519	if (new_creds == NULL) {
3520		new_creds = prepare_creds();
3521		if (!new_creds)
3522			return -ENOMEM;
3523	}
3524
3525	tsec = selinux_cred(new_creds);
3526	/* Get label from overlay inode and set it in create_sid */
3527	selinux_inode_getsecid(d_inode(src), &sid);
3528	tsec->create_sid = sid;
3529	*new = new_creds;
3530	return 0;
3531}
3532
3533static int selinux_inode_copy_up_xattr(const char *name)
3534{
3535	/* The copy_up hook above sets the initial context on an inode, but we
3536	 * don't then want to overwrite it by blindly copying all the lower
3537	 * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3538	 */
3539	if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3540		return 1; /* Discard */
3541	/*
3542	 * Any other attribute apart from SELINUX is not claimed, supported
3543	 * by selinux.
3544	 */
3545	return -EOPNOTSUPP;
3546}
3547
3548/* kernfs node operations */
3549
3550static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3551					struct kernfs_node *kn)
3552{
3553	const struct task_security_struct *tsec = selinux_cred(current_cred());
3554	u32 parent_sid, newsid, clen;
3555	int rc;
3556	char *context;
3557
3558	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3559	if (rc == -ENODATA)
3560		return 0;
3561	else if (rc < 0)
3562		return rc;
3563
3564	clen = (u32)rc;
3565	context = kmalloc(clen, GFP_KERNEL);
3566	if (!context)
3567		return -ENOMEM;
3568
3569	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3570	if (rc < 0) {
3571		kfree(context);
3572		return rc;
3573	}
3574
3575	rc = security_context_to_sid(context, clen, &parent_sid,
3576				     GFP_KERNEL);
3577	kfree(context);
3578	if (rc)
3579		return rc;
3580
3581	if (tsec->create_sid) {
3582		newsid = tsec->create_sid;
3583	} else {
3584		u16 secclass = inode_mode_to_security_class(kn->mode);
3585		struct qstr q;
3586
3587		q.name = kn->name;
3588		q.hash_len = hashlen_string(kn_dir, kn->name);
3589
3590		rc = security_transition_sid(tsec->sid,
3591					     parent_sid, secclass, &q,
3592					     &newsid);
3593		if (rc)
3594			return rc;
3595	}
3596
3597	rc = security_sid_to_context_force(newsid,
3598					   &context, &clen);
3599	if (rc)
3600		return rc;
3601
3602	rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3603			      XATTR_CREATE);
3604	kfree(context);
3605	return rc;
3606}
3607
3608
3609/* file security operations */
3610
3611static int selinux_revalidate_file_permission(struct file *file, int mask)
3612{
3613	const struct cred *cred = current_cred();
3614	struct inode *inode = file_inode(file);
3615
3616	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3617	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3618		mask |= MAY_APPEND;
3619
3620	return file_has_perm(cred, file,
3621			     file_mask_to_av(inode->i_mode, mask));
3622}
3623
3624static int selinux_file_permission(struct file *file, int mask)
3625{
3626	struct inode *inode = file_inode(file);
3627	struct file_security_struct *fsec = selinux_file(file);
3628	struct inode_security_struct *isec;
3629	u32 sid = current_sid();
3630
3631	if (!mask)
3632		/* No permission to check.  Existence test. */
3633		return 0;
3634
3635	isec = inode_security(inode);
3636	if (sid == fsec->sid && fsec->isid == isec->sid &&
3637	    fsec->pseqno == avc_policy_seqno())
3638		/* No change since file_open check. */
3639		return 0;
3640
3641	return selinux_revalidate_file_permission(file, mask);
3642}
3643
3644static int selinux_file_alloc_security(struct file *file)
3645{
3646	struct file_security_struct *fsec = selinux_file(file);
3647	u32 sid = current_sid();
3648
3649	fsec->sid = sid;
3650	fsec->fown_sid = sid;
3651
3652	return 0;
3653}
3654
3655/*
3656 * Check whether a task has the ioctl permission and cmd
3657 * operation to an inode.
3658 */
3659static int ioctl_has_perm(const struct cred *cred, struct file *file,
3660		u32 requested, u16 cmd)
3661{
3662	struct common_audit_data ad;
3663	struct file_security_struct *fsec = selinux_file(file);
3664	struct inode *inode = file_inode(file);
3665	struct inode_security_struct *isec;
3666	struct lsm_ioctlop_audit ioctl;
3667	u32 ssid = cred_sid(cred);
3668	int rc;
3669	u8 driver = cmd >> 8;
3670	u8 xperm = cmd & 0xff;
3671
3672	ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3673	ad.u.op = &ioctl;
3674	ad.u.op->cmd = cmd;
3675	ad.u.op->path = file->f_path;
3676
3677	if (ssid != fsec->sid) {
3678		rc = avc_has_perm(ssid, fsec->sid,
 
3679				SECCLASS_FD,
3680				FD__USE,
3681				&ad);
3682		if (rc)
3683			goto out;
3684	}
3685
3686	if (unlikely(IS_PRIVATE(inode)))
3687		return 0;
3688
3689	isec = inode_security(inode);
3690	rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
 
3691				    requested, driver, xperm, &ad);
3692out:
3693	return rc;
3694}
3695
3696static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3697			      unsigned long arg)
3698{
3699	const struct cred *cred = current_cred();
3700	int error = 0;
3701
3702	switch (cmd) {
3703	case FIONREAD:
3704	case FIBMAP:
3705	case FIGETBSZ:
3706	case FS_IOC_GETFLAGS:
3707	case FS_IOC_GETVERSION:
3708		error = file_has_perm(cred, file, FILE__GETATTR);
3709		break;
3710
3711	case FS_IOC_SETFLAGS:
3712	case FS_IOC_SETVERSION:
3713		error = file_has_perm(cred, file, FILE__SETATTR);
3714		break;
3715
3716	/* sys_ioctl() checks */
3717	case FIONBIO:
3718	case FIOASYNC:
3719		error = file_has_perm(cred, file, 0);
3720		break;
3721
3722	case KDSKBENT:
3723	case KDSKBSENT:
3724		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3725					    CAP_OPT_NONE, true);
3726		break;
3727
3728	case FIOCLEX:
3729	case FIONCLEX:
3730		if (!selinux_policycap_ioctl_skip_cloexec())
3731			error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3732		break;
3733
3734	/* default case assumes that the command will go
3735	 * to the file's ioctl() function.
3736	 */
3737	default:
3738		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3739	}
3740	return error;
3741}
3742
3743static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3744			      unsigned long arg)
3745{
3746	/*
3747	 * If we are in a 64-bit kernel running 32-bit userspace, we need to
3748	 * make sure we don't compare 32-bit flags to 64-bit flags.
3749	 */
3750	switch (cmd) {
3751	case FS_IOC32_GETFLAGS:
3752		cmd = FS_IOC_GETFLAGS;
3753		break;
3754	case FS_IOC32_SETFLAGS:
3755		cmd = FS_IOC_SETFLAGS;
3756		break;
3757	case FS_IOC32_GETVERSION:
3758		cmd = FS_IOC_GETVERSION;
3759		break;
3760	case FS_IOC32_SETVERSION:
3761		cmd = FS_IOC_SETVERSION;
3762		break;
3763	default:
3764		break;
3765	}
3766
3767	return selinux_file_ioctl(file, cmd, arg);
3768}
3769
3770static int default_noexec __ro_after_init;
3771
3772static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3773{
3774	const struct cred *cred = current_cred();
3775	u32 sid = cred_sid(cred);
3776	int rc = 0;
3777
3778	if (default_noexec &&
3779	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3780				   (!shared && (prot & PROT_WRITE)))) {
3781		/*
3782		 * We are making executable an anonymous mapping or a
3783		 * private file mapping that will also be writable.
3784		 * This has an additional check.
3785		 */
3786		rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
 
3787				  PROCESS__EXECMEM, NULL);
3788		if (rc)
3789			goto error;
3790	}
3791
3792	if (file) {
3793		/* read access is always possible with a mapping */
3794		u32 av = FILE__READ;
3795
3796		/* write access only matters if the mapping is shared */
3797		if (shared && (prot & PROT_WRITE))
3798			av |= FILE__WRITE;
3799
3800		if (prot & PROT_EXEC)
3801			av |= FILE__EXECUTE;
3802
3803		return file_has_perm(cred, file, av);
3804	}
3805
3806error:
3807	return rc;
3808}
3809
3810static int selinux_mmap_addr(unsigned long addr)
3811{
3812	int rc = 0;
3813
3814	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3815		u32 sid = current_sid();
3816		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
 
3817				  MEMPROTECT__MMAP_ZERO, NULL);
3818	}
3819
3820	return rc;
3821}
3822
3823static int selinux_mmap_file(struct file *file,
3824			     unsigned long reqprot __always_unused,
3825			     unsigned long prot, unsigned long flags)
3826{
3827	struct common_audit_data ad;
3828	int rc;
3829
3830	if (file) {
3831		ad.type = LSM_AUDIT_DATA_FILE;
3832		ad.u.file = file;
3833		rc = inode_has_perm(current_cred(), file_inode(file),
3834				    FILE__MAP, &ad);
3835		if (rc)
3836			return rc;
3837	}
3838
 
 
 
3839	return file_map_prot_check(file, prot,
3840				   (flags & MAP_TYPE) == MAP_SHARED);
3841}
3842
3843static int selinux_file_mprotect(struct vm_area_struct *vma,
3844				 unsigned long reqprot __always_unused,
3845				 unsigned long prot)
3846{
3847	const struct cred *cred = current_cred();
3848	u32 sid = cred_sid(cred);
3849
 
 
 
3850	if (default_noexec &&
3851	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3852		int rc = 0;
3853		if (vma_is_initial_heap(vma)) {
3854			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
 
 
3855					  PROCESS__EXECHEAP, NULL);
3856		} else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
 
 
3857			    vma_is_stack_for_current(vma))) {
3858			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
 
3859					  PROCESS__EXECSTACK, NULL);
3860		} else if (vma->vm_file && vma->anon_vma) {
3861			/*
3862			 * We are making executable a file mapping that has
3863			 * had some COW done. Since pages might have been
3864			 * written, check ability to execute the possibly
3865			 * modified content.  This typically should only
3866			 * occur for text relocations.
3867			 */
3868			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3869		}
3870		if (rc)
3871			return rc;
3872	}
3873
3874	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3875}
3876
3877static int selinux_file_lock(struct file *file, unsigned int cmd)
3878{
3879	const struct cred *cred = current_cred();
3880
3881	return file_has_perm(cred, file, FILE__LOCK);
3882}
3883
3884static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3885			      unsigned long arg)
3886{
3887	const struct cred *cred = current_cred();
3888	int err = 0;
3889
3890	switch (cmd) {
3891	case F_SETFL:
3892		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3893			err = file_has_perm(cred, file, FILE__WRITE);
3894			break;
3895		}
3896		fallthrough;
3897	case F_SETOWN:
3898	case F_SETSIG:
3899	case F_GETFL:
3900	case F_GETOWN:
3901	case F_GETSIG:
3902	case F_GETOWNER_UIDS:
3903		/* Just check FD__USE permission */
3904		err = file_has_perm(cred, file, 0);
3905		break;
3906	case F_GETLK:
3907	case F_SETLK:
3908	case F_SETLKW:
3909	case F_OFD_GETLK:
3910	case F_OFD_SETLK:
3911	case F_OFD_SETLKW:
3912#if BITS_PER_LONG == 32
3913	case F_GETLK64:
3914	case F_SETLK64:
3915	case F_SETLKW64:
3916#endif
3917		err = file_has_perm(cred, file, FILE__LOCK);
3918		break;
3919	}
3920
3921	return err;
3922}
3923
3924static void selinux_file_set_fowner(struct file *file)
3925{
3926	struct file_security_struct *fsec;
3927
3928	fsec = selinux_file(file);
3929	fsec->fown_sid = current_sid();
3930}
3931
3932static int selinux_file_send_sigiotask(struct task_struct *tsk,
3933				       struct fown_struct *fown, int signum)
3934{
3935	struct file *file;
3936	u32 sid = task_sid_obj(tsk);
3937	u32 perm;
3938	struct file_security_struct *fsec;
3939
3940	/* struct fown_struct is never outside the context of a struct file */
3941	file = container_of(fown, struct file, f_owner);
3942
3943	fsec = selinux_file(file);
3944
3945	if (!signum)
3946		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3947	else
3948		perm = signal_to_av(signum);
3949
3950	return avc_has_perm(fsec->fown_sid, sid,
 
3951			    SECCLASS_PROCESS, perm, NULL);
3952}
3953
3954static int selinux_file_receive(struct file *file)
3955{
3956	const struct cred *cred = current_cred();
3957
3958	return file_has_perm(cred, file, file_to_av(file));
3959}
3960
3961static int selinux_file_open(struct file *file)
3962{
3963	struct file_security_struct *fsec;
3964	struct inode_security_struct *isec;
3965
3966	fsec = selinux_file(file);
3967	isec = inode_security(file_inode(file));
3968	/*
3969	 * Save inode label and policy sequence number
3970	 * at open-time so that selinux_file_permission
3971	 * can determine whether revalidation is necessary.
3972	 * Task label is already saved in the file security
3973	 * struct as its SID.
3974	 */
3975	fsec->isid = isec->sid;
3976	fsec->pseqno = avc_policy_seqno();
3977	/*
3978	 * Since the inode label or policy seqno may have changed
3979	 * between the selinux_inode_permission check and the saving
3980	 * of state above, recheck that access is still permitted.
3981	 * Otherwise, access might never be revalidated against the
3982	 * new inode label or new policy.
3983	 * This check is not redundant - do not remove.
3984	 */
3985	return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3986}
3987
3988/* task security operations */
3989
3990static int selinux_task_alloc(struct task_struct *task,
3991			      unsigned long clone_flags)
3992{
3993	u32 sid = current_sid();
3994
3995	return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
 
3996}
3997
3998/*
3999 * prepare a new set of credentials for modification
4000 */
4001static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4002				gfp_t gfp)
4003{
4004	const struct task_security_struct *old_tsec = selinux_cred(old);
4005	struct task_security_struct *tsec = selinux_cred(new);
4006
4007	*tsec = *old_tsec;
4008	return 0;
4009}
4010
4011/*
4012 * transfer the SELinux data to a blank set of creds
4013 */
4014static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4015{
4016	const struct task_security_struct *old_tsec = selinux_cred(old);
4017	struct task_security_struct *tsec = selinux_cred(new);
4018
4019	*tsec = *old_tsec;
4020}
4021
4022static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4023{
4024	*secid = cred_sid(c);
4025}
4026
4027/*
4028 * set the security data for a kernel service
4029 * - all the creation contexts are set to unlabelled
4030 */
4031static int selinux_kernel_act_as(struct cred *new, u32 secid)
4032{
4033	struct task_security_struct *tsec = selinux_cred(new);
4034	u32 sid = current_sid();
4035	int ret;
4036
4037	ret = avc_has_perm(sid, secid,
 
4038			   SECCLASS_KERNEL_SERVICE,
4039			   KERNEL_SERVICE__USE_AS_OVERRIDE,
4040			   NULL);
4041	if (ret == 0) {
4042		tsec->sid = secid;
4043		tsec->create_sid = 0;
4044		tsec->keycreate_sid = 0;
4045		tsec->sockcreate_sid = 0;
4046	}
4047	return ret;
4048}
4049
4050/*
4051 * set the file creation context in a security record to the same as the
4052 * objective context of the specified inode
4053 */
4054static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4055{
4056	struct inode_security_struct *isec = inode_security(inode);
4057	struct task_security_struct *tsec = selinux_cred(new);
4058	u32 sid = current_sid();
4059	int ret;
4060
4061	ret = avc_has_perm(sid, isec->sid,
 
4062			   SECCLASS_KERNEL_SERVICE,
4063			   KERNEL_SERVICE__CREATE_FILES_AS,
4064			   NULL);
4065
4066	if (ret == 0)
4067		tsec->create_sid = isec->sid;
4068	return ret;
4069}
4070
4071static int selinux_kernel_module_request(char *kmod_name)
4072{
4073	struct common_audit_data ad;
4074
4075	ad.type = LSM_AUDIT_DATA_KMOD;
4076	ad.u.kmod_name = kmod_name;
4077
4078	return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
 
4079			    SYSTEM__MODULE_REQUEST, &ad);
4080}
4081
4082static int selinux_kernel_module_from_file(struct file *file)
4083{
4084	struct common_audit_data ad;
4085	struct inode_security_struct *isec;
4086	struct file_security_struct *fsec;
4087	u32 sid = current_sid();
4088	int rc;
4089
4090	/* init_module */
4091	if (file == NULL)
4092		return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
 
4093					SYSTEM__MODULE_LOAD, NULL);
4094
4095	/* finit_module */
4096
4097	ad.type = LSM_AUDIT_DATA_FILE;
4098	ad.u.file = file;
4099
4100	fsec = selinux_file(file);
4101	if (sid != fsec->sid) {
4102		rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
 
4103		if (rc)
4104			return rc;
4105	}
4106
4107	isec = inode_security(file_inode(file));
4108	return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
 
4109				SYSTEM__MODULE_LOAD, &ad);
4110}
4111
4112static int selinux_kernel_read_file(struct file *file,
4113				    enum kernel_read_file_id id,
4114				    bool contents)
4115{
4116	int rc = 0;
4117
4118	switch (id) {
4119	case READING_MODULE:
4120		rc = selinux_kernel_module_from_file(contents ? file : NULL);
4121		break;
4122	default:
4123		break;
4124	}
4125
4126	return rc;
4127}
4128
4129static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4130{
4131	int rc = 0;
4132
4133	switch (id) {
4134	case LOADING_MODULE:
4135		rc = selinux_kernel_module_from_file(NULL);
4136		break;
4137	default:
4138		break;
4139	}
4140
4141	return rc;
4142}
4143
4144static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4145{
4146	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
 
4147			    PROCESS__SETPGID, NULL);
4148}
4149
4150static int selinux_task_getpgid(struct task_struct *p)
4151{
4152	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
 
4153			    PROCESS__GETPGID, NULL);
4154}
4155
4156static int selinux_task_getsid(struct task_struct *p)
4157{
4158	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
 
4159			    PROCESS__GETSESSION, NULL);
4160}
4161
4162static void selinux_current_getsecid_subj(u32 *secid)
4163{
4164	*secid = current_sid();
4165}
4166
4167static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid)
4168{
4169	*secid = task_sid_obj(p);
4170}
4171
4172static int selinux_task_setnice(struct task_struct *p, int nice)
4173{
4174	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
 
4175			    PROCESS__SETSCHED, NULL);
4176}
4177
4178static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4179{
4180	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
 
4181			    PROCESS__SETSCHED, NULL);
4182}
4183
4184static int selinux_task_getioprio(struct task_struct *p)
4185{
4186	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
 
4187			    PROCESS__GETSCHED, NULL);
4188}
4189
4190static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4191				unsigned int flags)
4192{
4193	u32 av = 0;
4194
4195	if (!flags)
4196		return 0;
4197	if (flags & LSM_PRLIMIT_WRITE)
4198		av |= PROCESS__SETRLIMIT;
4199	if (flags & LSM_PRLIMIT_READ)
4200		av |= PROCESS__GETRLIMIT;
4201	return avc_has_perm(cred_sid(cred), cred_sid(tcred),
 
4202			    SECCLASS_PROCESS, av, NULL);
4203}
4204
4205static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4206		struct rlimit *new_rlim)
4207{
4208	struct rlimit *old_rlim = p->signal->rlim + resource;
4209
4210	/* Control the ability to change the hard limit (whether
4211	   lowering or raising it), so that the hard limit can
4212	   later be used as a safe reset point for the soft limit
4213	   upon context transitions.  See selinux_bprm_committing_creds. */
4214	if (old_rlim->rlim_max != new_rlim->rlim_max)
4215		return avc_has_perm(current_sid(), task_sid_obj(p),
 
4216				    SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4217
4218	return 0;
4219}
4220
4221static int selinux_task_setscheduler(struct task_struct *p)
4222{
4223	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
 
4224			    PROCESS__SETSCHED, NULL);
4225}
4226
4227static int selinux_task_getscheduler(struct task_struct *p)
4228{
4229	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
 
4230			    PROCESS__GETSCHED, NULL);
4231}
4232
4233static int selinux_task_movememory(struct task_struct *p)
4234{
4235	return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
 
4236			    PROCESS__SETSCHED, NULL);
4237}
4238
4239static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4240				int sig, const struct cred *cred)
4241{
4242	u32 secid;
4243	u32 perm;
4244
4245	if (!sig)
4246		perm = PROCESS__SIGNULL; /* null signal; existence test */
4247	else
4248		perm = signal_to_av(sig);
4249	if (!cred)
4250		secid = current_sid();
4251	else
4252		secid = cred_sid(cred);
4253	return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
 
4254}
4255
4256static void selinux_task_to_inode(struct task_struct *p,
4257				  struct inode *inode)
4258{
4259	struct inode_security_struct *isec = selinux_inode(inode);
4260	u32 sid = task_sid_obj(p);
4261
4262	spin_lock(&isec->lock);
4263	isec->sclass = inode_mode_to_security_class(inode->i_mode);
4264	isec->sid = sid;
4265	isec->initialized = LABEL_INITIALIZED;
4266	spin_unlock(&isec->lock);
4267}
4268
4269static int selinux_userns_create(const struct cred *cred)
4270{
4271	u32 sid = current_sid();
4272
4273	return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4274			USER_NAMESPACE__CREATE, NULL);
4275}
4276
4277/* Returns error only if unable to parse addresses */
4278static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4279			struct common_audit_data *ad, u8 *proto)
4280{
4281	int offset, ihlen, ret = -EINVAL;
4282	struct iphdr _iph, *ih;
4283
4284	offset = skb_network_offset(skb);
4285	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4286	if (ih == NULL)
4287		goto out;
4288
4289	ihlen = ih->ihl * 4;
4290	if (ihlen < sizeof(_iph))
4291		goto out;
4292
4293	ad->u.net->v4info.saddr = ih->saddr;
4294	ad->u.net->v4info.daddr = ih->daddr;
4295	ret = 0;
4296
4297	if (proto)
4298		*proto = ih->protocol;
4299
4300	switch (ih->protocol) {
4301	case IPPROTO_TCP: {
4302		struct tcphdr _tcph, *th;
4303
4304		if (ntohs(ih->frag_off) & IP_OFFSET)
4305			break;
4306
4307		offset += ihlen;
4308		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4309		if (th == NULL)
4310			break;
4311
4312		ad->u.net->sport = th->source;
4313		ad->u.net->dport = th->dest;
4314		break;
4315	}
4316
4317	case IPPROTO_UDP: {
4318		struct udphdr _udph, *uh;
4319
4320		if (ntohs(ih->frag_off) & IP_OFFSET)
4321			break;
4322
4323		offset += ihlen;
4324		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4325		if (uh == NULL)
4326			break;
4327
4328		ad->u.net->sport = uh->source;
4329		ad->u.net->dport = uh->dest;
4330		break;
4331	}
4332
4333	case IPPROTO_DCCP: {
4334		struct dccp_hdr _dccph, *dh;
4335
4336		if (ntohs(ih->frag_off) & IP_OFFSET)
4337			break;
4338
4339		offset += ihlen;
4340		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4341		if (dh == NULL)
4342			break;
4343
4344		ad->u.net->sport = dh->dccph_sport;
4345		ad->u.net->dport = dh->dccph_dport;
4346		break;
4347	}
4348
4349#if IS_ENABLED(CONFIG_IP_SCTP)
4350	case IPPROTO_SCTP: {
4351		struct sctphdr _sctph, *sh;
4352
4353		if (ntohs(ih->frag_off) & IP_OFFSET)
4354			break;
4355
4356		offset += ihlen;
4357		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4358		if (sh == NULL)
4359			break;
4360
4361		ad->u.net->sport = sh->source;
4362		ad->u.net->dport = sh->dest;
4363		break;
4364	}
4365#endif
4366	default:
4367		break;
4368	}
4369out:
4370	return ret;
4371}
4372
4373#if IS_ENABLED(CONFIG_IPV6)
4374
4375/* Returns error only if unable to parse addresses */
4376static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4377			struct common_audit_data *ad, u8 *proto)
4378{
4379	u8 nexthdr;
4380	int ret = -EINVAL, offset;
4381	struct ipv6hdr _ipv6h, *ip6;
4382	__be16 frag_off;
4383
4384	offset = skb_network_offset(skb);
4385	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4386	if (ip6 == NULL)
4387		goto out;
4388
4389	ad->u.net->v6info.saddr = ip6->saddr;
4390	ad->u.net->v6info.daddr = ip6->daddr;
4391	ret = 0;
4392
4393	nexthdr = ip6->nexthdr;
4394	offset += sizeof(_ipv6h);
4395	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4396	if (offset < 0)
4397		goto out;
4398
4399	if (proto)
4400		*proto = nexthdr;
4401
4402	switch (nexthdr) {
4403	case IPPROTO_TCP: {
4404		struct tcphdr _tcph, *th;
4405
4406		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4407		if (th == NULL)
4408			break;
4409
4410		ad->u.net->sport = th->source;
4411		ad->u.net->dport = th->dest;
4412		break;
4413	}
4414
4415	case IPPROTO_UDP: {
4416		struct udphdr _udph, *uh;
4417
4418		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4419		if (uh == NULL)
4420			break;
4421
4422		ad->u.net->sport = uh->source;
4423		ad->u.net->dport = uh->dest;
4424		break;
4425	}
4426
4427	case IPPROTO_DCCP: {
4428		struct dccp_hdr _dccph, *dh;
4429
4430		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4431		if (dh == NULL)
4432			break;
4433
4434		ad->u.net->sport = dh->dccph_sport;
4435		ad->u.net->dport = dh->dccph_dport;
4436		break;
4437	}
4438
4439#if IS_ENABLED(CONFIG_IP_SCTP)
4440	case IPPROTO_SCTP: {
4441		struct sctphdr _sctph, *sh;
4442
4443		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4444		if (sh == NULL)
4445			break;
4446
4447		ad->u.net->sport = sh->source;
4448		ad->u.net->dport = sh->dest;
4449		break;
4450	}
4451#endif
4452	/* includes fragments */
4453	default:
4454		break;
4455	}
4456out:
4457	return ret;
4458}
4459
4460#endif /* IPV6 */
4461
4462static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4463			     char **_addrp, int src, u8 *proto)
4464{
4465	char *addrp;
4466	int ret;
4467
4468	switch (ad->u.net->family) {
4469	case PF_INET:
4470		ret = selinux_parse_skb_ipv4(skb, ad, proto);
4471		if (ret)
4472			goto parse_error;
4473		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4474				       &ad->u.net->v4info.daddr);
4475		goto okay;
4476
4477#if IS_ENABLED(CONFIG_IPV6)
4478	case PF_INET6:
4479		ret = selinux_parse_skb_ipv6(skb, ad, proto);
4480		if (ret)
4481			goto parse_error;
4482		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4483				       &ad->u.net->v6info.daddr);
4484		goto okay;
4485#endif	/* IPV6 */
4486	default:
4487		addrp = NULL;
4488		goto okay;
4489	}
4490
4491parse_error:
4492	pr_warn(
4493	       "SELinux: failure in selinux_parse_skb(),"
4494	       " unable to parse packet\n");
4495	return ret;
4496
4497okay:
4498	if (_addrp)
4499		*_addrp = addrp;
4500	return 0;
4501}
4502
4503/**
4504 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4505 * @skb: the packet
4506 * @family: protocol family
4507 * @sid: the packet's peer label SID
4508 *
4509 * Description:
4510 * Check the various different forms of network peer labeling and determine
4511 * the peer label/SID for the packet; most of the magic actually occurs in
4512 * the security server function security_net_peersid_cmp().  The function
4513 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4514 * or -EACCES if @sid is invalid due to inconsistencies with the different
4515 * peer labels.
4516 *
4517 */
4518static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4519{
4520	int err;
4521	u32 xfrm_sid;
4522	u32 nlbl_sid;
4523	u32 nlbl_type;
4524
4525	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4526	if (unlikely(err))
4527		return -EACCES;
4528	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4529	if (unlikely(err))
4530		return -EACCES;
4531
4532	err = security_net_peersid_resolve(nlbl_sid,
4533					   nlbl_type, xfrm_sid, sid);
4534	if (unlikely(err)) {
4535		pr_warn(
4536		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
4537		       " unable to determine packet's peer label\n");
4538		return -EACCES;
4539	}
4540
4541	return 0;
4542}
4543
4544/**
4545 * selinux_conn_sid - Determine the child socket label for a connection
4546 * @sk_sid: the parent socket's SID
4547 * @skb_sid: the packet's SID
4548 * @conn_sid: the resulting connection SID
4549 *
4550 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4551 * combined with the MLS information from @skb_sid in order to create
4552 * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4553 * of @sk_sid.  Returns zero on success, negative values on failure.
4554 *
4555 */
4556static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4557{
4558	int err = 0;
4559
4560	if (skb_sid != SECSID_NULL)
4561		err = security_sid_mls_copy(sk_sid, skb_sid,
4562					    conn_sid);
4563	else
4564		*conn_sid = sk_sid;
4565
4566	return err;
4567}
4568
4569/* socket security operations */
4570
4571static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4572				 u16 secclass, u32 *socksid)
4573{
4574	if (tsec->sockcreate_sid > SECSID_NULL) {
4575		*socksid = tsec->sockcreate_sid;
4576		return 0;
4577	}
4578
4579	return security_transition_sid(tsec->sid, tsec->sid,
4580				       secclass, NULL, socksid);
4581}
4582
4583static int sock_has_perm(struct sock *sk, u32 perms)
4584{
4585	struct sk_security_struct *sksec = sk->sk_security;
4586	struct common_audit_data ad;
4587	struct lsm_network_audit net;
4588
4589	if (sksec->sid == SECINITSID_KERNEL)
4590		return 0;
4591
4592	/*
4593	 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4594	 * inherited the kernel context from early boot used to be skipped
4595	 * here, so preserve that behavior unless the capability is set.
4596	 *
4597	 * By setting the capability the policy signals that it is ready
4598	 * for this quirk to be fixed. Note that sockets created by a kernel
4599	 * thread or a usermode helper executed without a transition will
4600	 * still be skipped in this check regardless of the policycap
4601	 * setting.
4602	 */
4603	if (!selinux_policycap_userspace_initial_context() &&
4604	    sksec->sid == SECINITSID_INIT)
4605		return 0;
4606
4607	ad_net_init_from_sk(&ad, &net, sk);
4608
4609	return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
 
4610			    &ad);
4611}
4612
4613static int selinux_socket_create(int family, int type,
4614				 int protocol, int kern)
4615{
4616	const struct task_security_struct *tsec = selinux_cred(current_cred());
4617	u32 newsid;
4618	u16 secclass;
4619	int rc;
4620
4621	if (kern)
4622		return 0;
4623
4624	secclass = socket_type_to_security_class(family, type, protocol);
4625	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4626	if (rc)
4627		return rc;
4628
4629	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
 
4630}
4631
4632static int selinux_socket_post_create(struct socket *sock, int family,
4633				      int type, int protocol, int kern)
4634{
4635	const struct task_security_struct *tsec = selinux_cred(current_cred());
4636	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4637	struct sk_security_struct *sksec;
4638	u16 sclass = socket_type_to_security_class(family, type, protocol);
4639	u32 sid = SECINITSID_KERNEL;
4640	int err = 0;
4641
4642	if (!kern) {
4643		err = socket_sockcreate_sid(tsec, sclass, &sid);
4644		if (err)
4645			return err;
4646	}
4647
4648	isec->sclass = sclass;
4649	isec->sid = sid;
4650	isec->initialized = LABEL_INITIALIZED;
4651
4652	if (sock->sk) {
4653		sksec = sock->sk->sk_security;
4654		sksec->sclass = sclass;
4655		sksec->sid = sid;
4656		/* Allows detection of the first association on this socket */
4657		if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4658			sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4659
4660		err = selinux_netlbl_socket_post_create(sock->sk, family);
4661	}
4662
4663	return err;
4664}
4665
4666static int selinux_socket_socketpair(struct socket *socka,
4667				     struct socket *sockb)
4668{
4669	struct sk_security_struct *sksec_a = socka->sk->sk_security;
4670	struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4671
4672	sksec_a->peer_sid = sksec_b->sid;
4673	sksec_b->peer_sid = sksec_a->sid;
4674
4675	return 0;
4676}
4677
4678/* Range of port numbers used to automatically bind.
4679   Need to determine whether we should perform a name_bind
4680   permission check between the socket and the port number. */
4681
4682static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4683{
4684	struct sock *sk = sock->sk;
4685	struct sk_security_struct *sksec = sk->sk_security;
4686	u16 family;
4687	int err;
4688
4689	err = sock_has_perm(sk, SOCKET__BIND);
4690	if (err)
4691		goto out;
4692
4693	/* If PF_INET or PF_INET6, check name_bind permission for the port. */
4694	family = sk->sk_family;
4695	if (family == PF_INET || family == PF_INET6) {
4696		char *addrp;
4697		struct common_audit_data ad;
4698		struct lsm_network_audit net = {0,};
4699		struct sockaddr_in *addr4 = NULL;
4700		struct sockaddr_in6 *addr6 = NULL;
4701		u16 family_sa;
4702		unsigned short snum;
4703		u32 sid, node_perm;
4704
4705		/*
4706		 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4707		 * that validates multiple binding addresses. Because of this
4708		 * need to check address->sa_family as it is possible to have
4709		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4710		 */
4711		if (addrlen < offsetofend(struct sockaddr, sa_family))
4712			return -EINVAL;
4713		family_sa = address->sa_family;
4714		switch (family_sa) {
4715		case AF_UNSPEC:
4716		case AF_INET:
4717			if (addrlen < sizeof(struct sockaddr_in))
4718				return -EINVAL;
4719			addr4 = (struct sockaddr_in *)address;
4720			if (family_sa == AF_UNSPEC) {
4721				if (family == PF_INET6) {
4722					/* Length check from inet6_bind_sk() */
4723					if (addrlen < SIN6_LEN_RFC2133)
4724						return -EINVAL;
4725					/* Family check from __inet6_bind() */
4726					goto err_af;
4727				}
4728				/* see __inet_bind(), we only want to allow
4729				 * AF_UNSPEC if the address is INADDR_ANY
4730				 */
4731				if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4732					goto err_af;
4733				family_sa = AF_INET;
4734			}
4735			snum = ntohs(addr4->sin_port);
4736			addrp = (char *)&addr4->sin_addr.s_addr;
4737			break;
4738		case AF_INET6:
4739			if (addrlen < SIN6_LEN_RFC2133)
4740				return -EINVAL;
4741			addr6 = (struct sockaddr_in6 *)address;
4742			snum = ntohs(addr6->sin6_port);
4743			addrp = (char *)&addr6->sin6_addr.s6_addr;
4744			break;
4745		default:
4746			goto err_af;
4747		}
4748
4749		ad.type = LSM_AUDIT_DATA_NET;
4750		ad.u.net = &net;
4751		ad.u.net->sport = htons(snum);
4752		ad.u.net->family = family_sa;
4753
4754		if (snum) {
4755			int low, high;
4756
4757			inet_get_local_port_range(sock_net(sk), &low, &high);
4758
4759			if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4760			    snum < low || snum > high) {
4761				err = sel_netport_sid(sk->sk_protocol,
4762						      snum, &sid);
4763				if (err)
4764					goto out;
4765				err = avc_has_perm(sksec->sid, sid,
 
4766						   sksec->sclass,
4767						   SOCKET__NAME_BIND, &ad);
4768				if (err)
4769					goto out;
4770			}
4771		}
4772
4773		switch (sksec->sclass) {
4774		case SECCLASS_TCP_SOCKET:
4775			node_perm = TCP_SOCKET__NODE_BIND;
4776			break;
4777
4778		case SECCLASS_UDP_SOCKET:
4779			node_perm = UDP_SOCKET__NODE_BIND;
4780			break;
4781
4782		case SECCLASS_DCCP_SOCKET:
4783			node_perm = DCCP_SOCKET__NODE_BIND;
4784			break;
4785
4786		case SECCLASS_SCTP_SOCKET:
4787			node_perm = SCTP_SOCKET__NODE_BIND;
4788			break;
4789
4790		default:
4791			node_perm = RAWIP_SOCKET__NODE_BIND;
4792			break;
4793		}
4794
4795		err = sel_netnode_sid(addrp, family_sa, &sid);
4796		if (err)
4797			goto out;
4798
4799		if (family_sa == AF_INET)
4800			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4801		else
4802			ad.u.net->v6info.saddr = addr6->sin6_addr;
4803
4804		err = avc_has_perm(sksec->sid, sid,
 
4805				   sksec->sclass, node_perm, &ad);
4806		if (err)
4807			goto out;
4808	}
4809out:
4810	return err;
4811err_af:
4812	/* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4813	if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4814		return -EINVAL;
4815	return -EAFNOSUPPORT;
4816}
4817
4818/* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4819 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4820 */
4821static int selinux_socket_connect_helper(struct socket *sock,
4822					 struct sockaddr *address, int addrlen)
4823{
4824	struct sock *sk = sock->sk;
4825	struct sk_security_struct *sksec = sk->sk_security;
4826	int err;
4827
4828	err = sock_has_perm(sk, SOCKET__CONNECT);
4829	if (err)
4830		return err;
4831	if (addrlen < offsetofend(struct sockaddr, sa_family))
4832		return -EINVAL;
4833
4834	/* connect(AF_UNSPEC) has special handling, as it is a documented
4835	 * way to disconnect the socket
4836	 */
4837	if (address->sa_family == AF_UNSPEC)
4838		return 0;
4839
4840	/*
4841	 * If a TCP, DCCP or SCTP socket, check name_connect permission
4842	 * for the port.
4843	 */
4844	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4845	    sksec->sclass == SECCLASS_DCCP_SOCKET ||
4846	    sksec->sclass == SECCLASS_SCTP_SOCKET) {
4847		struct common_audit_data ad;
4848		struct lsm_network_audit net = {0,};
4849		struct sockaddr_in *addr4 = NULL;
4850		struct sockaddr_in6 *addr6 = NULL;
4851		unsigned short snum;
4852		u32 sid, perm;
4853
4854		/* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4855		 * that validates multiple connect addresses. Because of this
4856		 * need to check address->sa_family as it is possible to have
4857		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4858		 */
4859		switch (address->sa_family) {
4860		case AF_INET:
4861			addr4 = (struct sockaddr_in *)address;
4862			if (addrlen < sizeof(struct sockaddr_in))
4863				return -EINVAL;
4864			snum = ntohs(addr4->sin_port);
4865			break;
4866		case AF_INET6:
4867			addr6 = (struct sockaddr_in6 *)address;
4868			if (addrlen < SIN6_LEN_RFC2133)
4869				return -EINVAL;
4870			snum = ntohs(addr6->sin6_port);
4871			break;
4872		default:
4873			/* Note that SCTP services expect -EINVAL, whereas
4874			 * others expect -EAFNOSUPPORT.
4875			 */
4876			if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4877				return -EINVAL;
4878			else
4879				return -EAFNOSUPPORT;
4880		}
4881
4882		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4883		if (err)
4884			return err;
4885
4886		switch (sksec->sclass) {
4887		case SECCLASS_TCP_SOCKET:
4888			perm = TCP_SOCKET__NAME_CONNECT;
4889			break;
4890		case SECCLASS_DCCP_SOCKET:
4891			perm = DCCP_SOCKET__NAME_CONNECT;
4892			break;
4893		case SECCLASS_SCTP_SOCKET:
4894			perm = SCTP_SOCKET__NAME_CONNECT;
4895			break;
4896		}
4897
4898		ad.type = LSM_AUDIT_DATA_NET;
4899		ad.u.net = &net;
4900		ad.u.net->dport = htons(snum);
4901		ad.u.net->family = address->sa_family;
4902		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
 
4903		if (err)
4904			return err;
4905	}
4906
4907	return 0;
4908}
4909
4910/* Supports connect(2), see comments in selinux_socket_connect_helper() */
4911static int selinux_socket_connect(struct socket *sock,
4912				  struct sockaddr *address, int addrlen)
4913{
4914	int err;
4915	struct sock *sk = sock->sk;
4916
4917	err = selinux_socket_connect_helper(sock, address, addrlen);
4918	if (err)
4919		return err;
4920
4921	return selinux_netlbl_socket_connect(sk, address);
4922}
4923
4924static int selinux_socket_listen(struct socket *sock, int backlog)
4925{
4926	return sock_has_perm(sock->sk, SOCKET__LISTEN);
4927}
4928
4929static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4930{
4931	int err;
4932	struct inode_security_struct *isec;
4933	struct inode_security_struct *newisec;
4934	u16 sclass;
4935	u32 sid;
4936
4937	err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4938	if (err)
4939		return err;
4940
4941	isec = inode_security_novalidate(SOCK_INODE(sock));
4942	spin_lock(&isec->lock);
4943	sclass = isec->sclass;
4944	sid = isec->sid;
4945	spin_unlock(&isec->lock);
4946
4947	newisec = inode_security_novalidate(SOCK_INODE(newsock));
4948	newisec->sclass = sclass;
4949	newisec->sid = sid;
4950	newisec->initialized = LABEL_INITIALIZED;
4951
4952	return 0;
4953}
4954
4955static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4956				  int size)
4957{
4958	return sock_has_perm(sock->sk, SOCKET__WRITE);
4959}
4960
4961static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4962				  int size, int flags)
4963{
4964	return sock_has_perm(sock->sk, SOCKET__READ);
4965}
4966
4967static int selinux_socket_getsockname(struct socket *sock)
4968{
4969	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4970}
4971
4972static int selinux_socket_getpeername(struct socket *sock)
4973{
4974	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4975}
4976
4977static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4978{
4979	int err;
4980
4981	err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4982	if (err)
4983		return err;
4984
4985	return selinux_netlbl_socket_setsockopt(sock, level, optname);
4986}
4987
4988static int selinux_socket_getsockopt(struct socket *sock, int level,
4989				     int optname)
4990{
4991	return sock_has_perm(sock->sk, SOCKET__GETOPT);
4992}
4993
4994static int selinux_socket_shutdown(struct socket *sock, int how)
4995{
4996	return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4997}
4998
4999static int selinux_socket_unix_stream_connect(struct sock *sock,
5000					      struct sock *other,
5001					      struct sock *newsk)
5002{
5003	struct sk_security_struct *sksec_sock = sock->sk_security;
5004	struct sk_security_struct *sksec_other = other->sk_security;
5005	struct sk_security_struct *sksec_new = newsk->sk_security;
5006	struct common_audit_data ad;
5007	struct lsm_network_audit net;
5008	int err;
5009
5010	ad_net_init_from_sk(&ad, &net, other);
 
 
5011
5012	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
 
5013			   sksec_other->sclass,
5014			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5015	if (err)
5016		return err;
5017
5018	/* server child socket */
5019	sksec_new->peer_sid = sksec_sock->sid;
5020	err = security_sid_mls_copy(sksec_other->sid,
5021				    sksec_sock->sid, &sksec_new->sid);
5022	if (err)
5023		return err;
5024
5025	/* connecting socket */
5026	sksec_sock->peer_sid = sksec_new->sid;
5027
5028	return 0;
5029}
5030
5031static int selinux_socket_unix_may_send(struct socket *sock,
5032					struct socket *other)
5033{
5034	struct sk_security_struct *ssec = sock->sk->sk_security;
5035	struct sk_security_struct *osec = other->sk->sk_security;
5036	struct common_audit_data ad;
5037	struct lsm_network_audit net;
5038
5039	ad_net_init_from_sk(&ad, &net, other->sk);
 
 
5040
5041	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
 
5042			    &ad);
5043}
5044
5045static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5046				    char *addrp, u16 family, u32 peer_sid,
5047				    struct common_audit_data *ad)
5048{
5049	int err;
5050	u32 if_sid;
5051	u32 node_sid;
5052
5053	err = sel_netif_sid(ns, ifindex, &if_sid);
5054	if (err)
5055		return err;
5056	err = avc_has_perm(peer_sid, if_sid,
 
5057			   SECCLASS_NETIF, NETIF__INGRESS, ad);
5058	if (err)
5059		return err;
5060
5061	err = sel_netnode_sid(addrp, family, &node_sid);
5062	if (err)
5063		return err;
5064	return avc_has_perm(peer_sid, node_sid,
 
5065			    SECCLASS_NODE, NODE__RECVFROM, ad);
5066}
5067
5068static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5069				       u16 family)
5070{
5071	int err = 0;
5072	struct sk_security_struct *sksec = sk->sk_security;
5073	u32 sk_sid = sksec->sid;
5074	struct common_audit_data ad;
5075	struct lsm_network_audit net;
5076	char *addrp;
5077
5078	ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
 
 
 
5079	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5080	if (err)
5081		return err;
5082
5083	if (selinux_secmark_enabled()) {
5084		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
 
5085				   PACKET__RECV, &ad);
5086		if (err)
5087			return err;
5088	}
5089
5090	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5091	if (err)
5092		return err;
5093	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5094
5095	return err;
5096}
5097
5098static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5099{
5100	int err, peerlbl_active, secmark_active;
5101	struct sk_security_struct *sksec = sk->sk_security;
5102	u16 family = sk->sk_family;
5103	u32 sk_sid = sksec->sid;
5104	struct common_audit_data ad;
5105	struct lsm_network_audit net;
5106	char *addrp;
 
 
5107
5108	if (family != PF_INET && family != PF_INET6)
5109		return 0;
5110
5111	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
5112	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5113		family = PF_INET;
5114
5115	/* If any sort of compatibility mode is enabled then handoff processing
5116	 * to the selinux_sock_rcv_skb_compat() function to deal with the
5117	 * special handling.  We do this in an attempt to keep this function
5118	 * as fast and as clean as possible. */
5119	if (!selinux_policycap_netpeer())
5120		return selinux_sock_rcv_skb_compat(sk, skb, family);
5121
5122	secmark_active = selinux_secmark_enabled();
5123	peerlbl_active = selinux_peerlbl_enabled();
5124	if (!secmark_active && !peerlbl_active)
5125		return 0;
5126
5127	ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
 
 
 
5128	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5129	if (err)
5130		return err;
5131
5132	if (peerlbl_active) {
5133		u32 peer_sid;
5134
5135		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5136		if (err)
5137			return err;
5138		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5139					       addrp, family, peer_sid, &ad);
5140		if (err) {
5141			selinux_netlbl_err(skb, family, err, 0);
5142			return err;
5143		}
5144		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
 
5145				   PEER__RECV, &ad);
5146		if (err) {
5147			selinux_netlbl_err(skb, family, err, 0);
5148			return err;
5149		}
5150	}
5151
5152	if (secmark_active) {
5153		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
 
5154				   PACKET__RECV, &ad);
5155		if (err)
5156			return err;
5157	}
5158
5159	return err;
5160}
5161
5162static int selinux_socket_getpeersec_stream(struct socket *sock,
5163					    sockptr_t optval, sockptr_t optlen,
5164					    unsigned int len)
5165{
5166	int err = 0;
5167	char *scontext = NULL;
5168	u32 scontext_len;
5169	struct sk_security_struct *sksec = sock->sk->sk_security;
5170	u32 peer_sid = SECSID_NULL;
5171
5172	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5173	    sksec->sclass == SECCLASS_TCP_SOCKET ||
5174	    sksec->sclass == SECCLASS_SCTP_SOCKET)
5175		peer_sid = sksec->peer_sid;
5176	if (peer_sid == SECSID_NULL)
5177		return -ENOPROTOOPT;
5178
5179	err = security_sid_to_context(peer_sid, &scontext,
5180				      &scontext_len);
5181	if (err)
5182		return err;
 
5183	if (scontext_len > len) {
5184		err = -ERANGE;
5185		goto out_len;
5186	}
5187
5188	if (copy_to_sockptr(optval, scontext, scontext_len))
5189		err = -EFAULT;
 
5190out_len:
5191	if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5192		err = -EFAULT;
5193	kfree(scontext);
5194	return err;
5195}
5196
5197static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5198{
5199	u32 peer_secid = SECSID_NULL;
5200	u16 family;
5201	struct inode_security_struct *isec;
5202
5203	if (skb && skb->protocol == htons(ETH_P_IP))
5204		family = PF_INET;
5205	else if (skb && skb->protocol == htons(ETH_P_IPV6))
5206		family = PF_INET6;
5207	else if (sock)
5208		family = sock->sk->sk_family;
5209	else
5210		goto out;
5211
5212	if (sock && family == PF_UNIX) {
5213		isec = inode_security_novalidate(SOCK_INODE(sock));
5214		peer_secid = isec->sid;
5215	} else if (skb)
5216		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5217
5218out:
5219	*secid = peer_secid;
5220	if (peer_secid == SECSID_NULL)
5221		return -EINVAL;
5222	return 0;
5223}
5224
5225static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5226{
5227	struct sk_security_struct *sksec;
5228
5229	sksec = kzalloc(sizeof(*sksec), priority);
5230	if (!sksec)
5231		return -ENOMEM;
5232
5233	sksec->peer_sid = SECINITSID_UNLABELED;
5234	sksec->sid = SECINITSID_UNLABELED;
5235	sksec->sclass = SECCLASS_SOCKET;
5236	selinux_netlbl_sk_security_reset(sksec);
5237	sk->sk_security = sksec;
5238
5239	return 0;
5240}
5241
5242static void selinux_sk_free_security(struct sock *sk)
5243{
5244	struct sk_security_struct *sksec = sk->sk_security;
5245
5246	sk->sk_security = NULL;
5247	selinux_netlbl_sk_security_free(sksec);
5248	kfree(sksec);
5249}
5250
5251static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5252{
5253	struct sk_security_struct *sksec = sk->sk_security;
5254	struct sk_security_struct *newsksec = newsk->sk_security;
5255
5256	newsksec->sid = sksec->sid;
5257	newsksec->peer_sid = sksec->peer_sid;
5258	newsksec->sclass = sksec->sclass;
5259
5260	selinux_netlbl_sk_security_reset(newsksec);
5261}
5262
5263static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5264{
5265	if (!sk)
5266		*secid = SECINITSID_ANY_SOCKET;
5267	else {
5268		const struct sk_security_struct *sksec = sk->sk_security;
5269
5270		*secid = sksec->sid;
5271	}
5272}
5273
5274static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5275{
5276	struct inode_security_struct *isec =
5277		inode_security_novalidate(SOCK_INODE(parent));
5278	struct sk_security_struct *sksec = sk->sk_security;
5279
5280	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5281	    sk->sk_family == PF_UNIX)
5282		isec->sid = sksec->sid;
5283	sksec->sclass = isec->sclass;
5284}
5285
5286/*
5287 * Determines peer_secid for the asoc and updates socket's peer label
5288 * if it's the first association on the socket.
5289 */
5290static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5291					  struct sk_buff *skb)
5292{
5293	struct sock *sk = asoc->base.sk;
5294	u16 family = sk->sk_family;
5295	struct sk_security_struct *sksec = sk->sk_security;
5296	struct common_audit_data ad;
5297	struct lsm_network_audit net;
5298	int err;
 
 
 
5299
5300	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5301	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5302		family = PF_INET;
5303
5304	if (selinux_peerlbl_enabled()) {
5305		asoc->peer_secid = SECSID_NULL;
5306
 
5307		/* This will return peer_sid = SECSID_NULL if there are
5308		 * no peer labels, see security_net_peersid_resolve().
5309		 */
5310		err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
 
5311		if (err)
5312			return err;
5313
5314		if (asoc->peer_secid == SECSID_NULL)
5315			asoc->peer_secid = SECINITSID_UNLABELED;
5316	} else {
5317		asoc->peer_secid = SECINITSID_UNLABELED;
5318	}
5319
5320	if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5321		sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5322
5323		/* Here as first association on socket. As the peer SID
5324		 * was allowed by peer recv (and the netif/node checks),
5325		 * then it is approved by policy and used as the primary
5326		 * peer SID for getpeercon(3).
5327		 */
5328		sksec->peer_sid = asoc->peer_secid;
5329	} else if (sksec->peer_sid != asoc->peer_secid) {
5330		/* Other association peer SIDs are checked to enforce
5331		 * consistency among the peer SIDs.
5332		 */
5333		ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5334		err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5335				   sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5336				   &ad);
 
 
5337		if (err)
5338			return err;
5339	}
5340	return 0;
5341}
5342
5343/* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5344 * happens on an incoming connect(2), sctp_connectx(3) or
5345 * sctp_sendmsg(3) (with no association already present).
5346 */
5347static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5348				      struct sk_buff *skb)
5349{
5350	struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5351	u32 conn_sid;
5352	int err;
5353
5354	if (!selinux_policycap_extsockclass())
5355		return 0;
5356
5357	err = selinux_sctp_process_new_assoc(asoc, skb);
5358	if (err)
5359		return err;
5360
5361	/* Compute the MLS component for the connection and store
5362	 * the information in asoc. This will be used by SCTP TCP type
5363	 * sockets and peeled off connections as they cause a new
5364	 * socket to be generated. selinux_sctp_sk_clone() will then
5365	 * plug this into the new socket.
5366	 */
5367	err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5368	if (err)
5369		return err;
5370
5371	asoc->secid = conn_sid;
 
5372
5373	/* Set any NetLabel labels including CIPSO/CALIPSO options. */
5374	return selinux_netlbl_sctp_assoc_request(asoc, skb);
5375}
5376
5377/* Called when SCTP receives a COOKIE ACK chunk as the final
5378 * response to an association request (initited by us).
5379 */
5380static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5381					  struct sk_buff *skb)
5382{
5383	struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5384
5385	if (!selinux_policycap_extsockclass())
5386		return 0;
5387
5388	/* Inherit secid from the parent socket - this will be picked up
5389	 * by selinux_sctp_sk_clone() if the association gets peeled off
5390	 * into a new socket.
5391	 */
5392	asoc->secid = sksec->sid;
5393
5394	return selinux_sctp_process_new_assoc(asoc, skb);
5395}
5396
5397/* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5398 * based on their @optname.
5399 */
5400static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5401				     struct sockaddr *address,
5402				     int addrlen)
5403{
5404	int len, err = 0, walk_size = 0;
5405	void *addr_buf;
5406	struct sockaddr *addr;
5407	struct socket *sock;
5408
5409	if (!selinux_policycap_extsockclass())
5410		return 0;
5411
5412	/* Process one or more addresses that may be IPv4 or IPv6 */
5413	sock = sk->sk_socket;
5414	addr_buf = address;
5415
5416	while (walk_size < addrlen) {
5417		if (walk_size + sizeof(sa_family_t) > addrlen)
5418			return -EINVAL;
5419
5420		addr = addr_buf;
5421		switch (addr->sa_family) {
5422		case AF_UNSPEC:
5423		case AF_INET:
5424			len = sizeof(struct sockaddr_in);
5425			break;
5426		case AF_INET6:
5427			len = sizeof(struct sockaddr_in6);
5428			break;
5429		default:
5430			return -EINVAL;
5431		}
5432
5433		if (walk_size + len > addrlen)
5434			return -EINVAL;
5435
5436		err = -EINVAL;
5437		switch (optname) {
5438		/* Bind checks */
5439		case SCTP_PRIMARY_ADDR:
5440		case SCTP_SET_PEER_PRIMARY_ADDR:
5441		case SCTP_SOCKOPT_BINDX_ADD:
5442			err = selinux_socket_bind(sock, addr, len);
5443			break;
5444		/* Connect checks */
5445		case SCTP_SOCKOPT_CONNECTX:
5446		case SCTP_PARAM_SET_PRIMARY:
5447		case SCTP_PARAM_ADD_IP:
5448		case SCTP_SENDMSG_CONNECT:
5449			err = selinux_socket_connect_helper(sock, addr, len);
5450			if (err)
5451				return err;
5452
5453			/* As selinux_sctp_bind_connect() is called by the
5454			 * SCTP protocol layer, the socket is already locked,
5455			 * therefore selinux_netlbl_socket_connect_locked()
5456			 * is called here. The situations handled are:
5457			 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5458			 * whenever a new IP address is added or when a new
5459			 * primary address is selected.
5460			 * Note that an SCTP connect(2) call happens before
5461			 * the SCTP protocol layer and is handled via
5462			 * selinux_socket_connect().
5463			 */
5464			err = selinux_netlbl_socket_connect_locked(sk, addr);
5465			break;
5466		}
5467
5468		if (err)
5469			return err;
5470
5471		addr_buf += len;
5472		walk_size += len;
5473	}
5474
5475	return 0;
5476}
5477
5478/* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5479static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5480				  struct sock *newsk)
5481{
5482	struct sk_security_struct *sksec = sk->sk_security;
5483	struct sk_security_struct *newsksec = newsk->sk_security;
5484
5485	/* If policy does not support SECCLASS_SCTP_SOCKET then call
5486	 * the non-sctp clone version.
5487	 */
5488	if (!selinux_policycap_extsockclass())
5489		return selinux_sk_clone_security(sk, newsk);
5490
5491	newsksec->sid = asoc->secid;
5492	newsksec->peer_sid = asoc->peer_secid;
5493	newsksec->sclass = sksec->sclass;
5494	selinux_netlbl_sctp_sk_clone(sk, newsk);
5495}
5496
5497static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5498{
5499	struct sk_security_struct *ssksec = ssk->sk_security;
5500	struct sk_security_struct *sksec = sk->sk_security;
5501
5502	ssksec->sclass = sksec->sclass;
5503	ssksec->sid = sksec->sid;
5504
5505	/* replace the existing subflow label deleting the existing one
5506	 * and re-recreating a new label using the updated context
5507	 */
5508	selinux_netlbl_sk_security_free(ssksec);
5509	return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5510}
5511
5512static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5513				     struct request_sock *req)
5514{
5515	struct sk_security_struct *sksec = sk->sk_security;
5516	int err;
5517	u16 family = req->rsk_ops->family;
5518	u32 connsid;
5519	u32 peersid;
5520
5521	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5522	if (err)
5523		return err;
5524	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5525	if (err)
5526		return err;
5527	req->secid = connsid;
5528	req->peer_secid = peersid;
5529
5530	return selinux_netlbl_inet_conn_request(req, family);
5531}
5532
5533static void selinux_inet_csk_clone(struct sock *newsk,
5534				   const struct request_sock *req)
5535{
5536	struct sk_security_struct *newsksec = newsk->sk_security;
5537
5538	newsksec->sid = req->secid;
5539	newsksec->peer_sid = req->peer_secid;
5540	/* NOTE: Ideally, we should also get the isec->sid for the
5541	   new socket in sync, but we don't have the isec available yet.
5542	   So we will wait until sock_graft to do it, by which
5543	   time it will have been created and available. */
5544
5545	/* We don't need to take any sort of lock here as we are the only
5546	 * thread with access to newsksec */
5547	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5548}
5549
5550static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5551{
5552	u16 family = sk->sk_family;
5553	struct sk_security_struct *sksec = sk->sk_security;
5554
5555	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5556	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5557		family = PF_INET;
5558
5559	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5560}
5561
5562static int selinux_secmark_relabel_packet(u32 sid)
5563{
5564	const struct task_security_struct *tsec;
5565	u32 tsid;
5566
5567	tsec = selinux_cred(current_cred());
5568	tsid = tsec->sid;
5569
5570	return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
 
5571			    NULL);
5572}
5573
5574static void selinux_secmark_refcount_inc(void)
5575{
5576	atomic_inc(&selinux_secmark_refcount);
5577}
5578
5579static void selinux_secmark_refcount_dec(void)
5580{
5581	atomic_dec(&selinux_secmark_refcount);
5582}
5583
5584static void selinux_req_classify_flow(const struct request_sock *req,
5585				      struct flowi_common *flic)
5586{
5587	flic->flowic_secid = req->secid;
5588}
5589
5590static int selinux_tun_dev_alloc_security(void **security)
5591{
5592	struct tun_security_struct *tunsec;
5593
5594	tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5595	if (!tunsec)
5596		return -ENOMEM;
5597	tunsec->sid = current_sid();
5598
5599	*security = tunsec;
5600	return 0;
5601}
5602
5603static void selinux_tun_dev_free_security(void *security)
5604{
5605	kfree(security);
5606}
5607
5608static int selinux_tun_dev_create(void)
5609{
5610	u32 sid = current_sid();
5611
5612	/* we aren't taking into account the "sockcreate" SID since the socket
5613	 * that is being created here is not a socket in the traditional sense,
5614	 * instead it is a private sock, accessible only to the kernel, and
5615	 * representing a wide range of network traffic spanning multiple
5616	 * connections unlike traditional sockets - check the TUN driver to
5617	 * get a better understanding of why this socket is special */
5618
5619	return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
 
5620			    NULL);
5621}
5622
5623static int selinux_tun_dev_attach_queue(void *security)
5624{
5625	struct tun_security_struct *tunsec = security;
5626
5627	return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
 
5628			    TUN_SOCKET__ATTACH_QUEUE, NULL);
5629}
5630
5631static int selinux_tun_dev_attach(struct sock *sk, void *security)
5632{
5633	struct tun_security_struct *tunsec = security;
5634	struct sk_security_struct *sksec = sk->sk_security;
5635
5636	/* we don't currently perform any NetLabel based labeling here and it
5637	 * isn't clear that we would want to do so anyway; while we could apply
5638	 * labeling without the support of the TUN user the resulting labeled
5639	 * traffic from the other end of the connection would almost certainly
5640	 * cause confusion to the TUN user that had no idea network labeling
5641	 * protocols were being used */
5642
5643	sksec->sid = tunsec->sid;
5644	sksec->sclass = SECCLASS_TUN_SOCKET;
5645
5646	return 0;
5647}
5648
5649static int selinux_tun_dev_open(void *security)
5650{
5651	struct tun_security_struct *tunsec = security;
5652	u32 sid = current_sid();
5653	int err;
5654
5655	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
 
5656			   TUN_SOCKET__RELABELFROM, NULL);
5657	if (err)
5658		return err;
5659	err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
 
5660			   TUN_SOCKET__RELABELTO, NULL);
5661	if (err)
5662		return err;
5663	tunsec->sid = sid;
5664
5665	return 0;
5666}
5667
5668#ifdef CONFIG_NETFILTER
5669
5670static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5671				       const struct nf_hook_state *state)
 
5672{
5673	int ifindex;
5674	u16 family;
5675	char *addrp;
5676	u32 peer_sid;
5677	struct common_audit_data ad;
5678	struct lsm_network_audit net;
5679	int secmark_active, peerlbl_active;
 
 
5680
5681	if (!selinux_policycap_netpeer())
5682		return NF_ACCEPT;
5683
5684	secmark_active = selinux_secmark_enabled();
 
5685	peerlbl_active = selinux_peerlbl_enabled();
5686	if (!secmark_active && !peerlbl_active)
5687		return NF_ACCEPT;
5688
5689	family = state->pf;
5690	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5691		return NF_DROP;
5692
5693	ifindex = state->in->ifindex;
5694	ad_net_init_from_iif(&ad, &net, ifindex, family);
 
 
5695	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5696		return NF_DROP;
5697
5698	if (peerlbl_active) {
5699		int err;
5700
5701		err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5702					       addrp, family, peer_sid, &ad);
5703		if (err) {
5704			selinux_netlbl_err(skb, family, err, 1);
5705			return NF_DROP;
5706		}
5707	}
5708
5709	if (secmark_active)
5710		if (avc_has_perm(peer_sid, skb->secmark,
 
5711				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5712			return NF_DROP;
5713
5714	if (netlbl_enabled())
5715		/* we do this in the FORWARD path and not the POST_ROUTING
5716		 * path because we want to make sure we apply the necessary
5717		 * labeling before IPsec is applied so we can leverage AH
5718		 * protection */
5719		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5720			return NF_DROP;
5721
5722	return NF_ACCEPT;
5723}
5724
5725static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5726				      const struct nf_hook_state *state)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5727{
5728	struct sock *sk;
5729	u32 sid;
5730
5731	if (!netlbl_enabled())
5732		return NF_ACCEPT;
5733
5734	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5735	 * because we want to make sure we apply the necessary labeling
5736	 * before IPsec is applied so we can leverage AH protection */
5737	sk = skb->sk;
5738	if (sk) {
5739		struct sk_security_struct *sksec;
5740
5741		if (sk_listener(sk))
5742			/* if the socket is the listening state then this
5743			 * packet is a SYN-ACK packet which means it needs to
5744			 * be labeled based on the connection/request_sock and
5745			 * not the parent socket.  unfortunately, we can't
5746			 * lookup the request_sock yet as it isn't queued on
5747			 * the parent socket until after the SYN-ACK is sent.
5748			 * the "solution" is to simply pass the packet as-is
5749			 * as any IP option based labeling should be copied
5750			 * from the initial connection request (in the IP
5751			 * layer).  it is far from ideal, but until we get a
5752			 * security label in the packet itself this is the
5753			 * best we can do. */
5754			return NF_ACCEPT;
5755
5756		/* standard practice, label using the parent socket */
5757		sksec = sk->sk_security;
5758		sid = sksec->sid;
5759	} else
5760		sid = SECINITSID_KERNEL;
5761	if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5762		return NF_DROP;
5763
5764	return NF_ACCEPT;
5765}
5766
 
 
 
 
 
 
5767
5768static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
 
 
5769					const struct nf_hook_state *state)
5770{
5771	struct sock *sk;
 
 
 
 
 
 
 
 
5772	struct sk_security_struct *sksec;
5773	struct common_audit_data ad;
5774	struct lsm_network_audit net;
5775	u8 proto = 0;
 
5776
5777	sk = skb_to_full_sk(skb);
5778	if (sk == NULL)
5779		return NF_ACCEPT;
5780	sksec = sk->sk_security;
5781
5782	ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5783	if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
 
 
 
5784		return NF_DROP;
5785
5786	if (selinux_secmark_enabled())
5787		if (avc_has_perm(sksec->sid, skb->secmark,
 
5788				 SECCLASS_PACKET, PACKET__SEND, &ad))
5789			return NF_DROP_ERR(-ECONNREFUSED);
5790
5791	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5792		return NF_DROP_ERR(-ECONNREFUSED);
5793
5794	return NF_ACCEPT;
5795}
5796
5797static unsigned int selinux_ip_postroute(void *priv,
5798					 struct sk_buff *skb,
5799					 const struct nf_hook_state *state)
5800{
5801	u16 family;
5802	u32 secmark_perm;
5803	u32 peer_sid;
5804	int ifindex;
5805	struct sock *sk;
5806	struct common_audit_data ad;
5807	struct lsm_network_audit net;
5808	char *addrp;
5809	int secmark_active, peerlbl_active;
 
5810
5811	/* If any sort of compatibility mode is enabled then handoff processing
5812	 * to the selinux_ip_postroute_compat() function to deal with the
5813	 * special handling.  We do this in an attempt to keep this function
5814	 * as fast and as clean as possible. */
5815	if (!selinux_policycap_netpeer())
5816		return selinux_ip_postroute_compat(skb, state);
5817
5818	secmark_active = selinux_secmark_enabled();
5819	peerlbl_active = selinux_peerlbl_enabled();
5820	if (!secmark_active && !peerlbl_active)
5821		return NF_ACCEPT;
5822
5823	sk = skb_to_full_sk(skb);
5824
5825#ifdef CONFIG_XFRM
5826	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5827	 * packet transformation so allow the packet to pass without any checks
5828	 * since we'll have another chance to perform access control checks
5829	 * when the packet is on it's final way out.
5830	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5831	 *       is NULL, in this case go ahead and apply access control.
5832	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5833	 *       TCP listening state we cannot wait until the XFRM processing
5834	 *       is done as we will miss out on the SA label if we do;
5835	 *       unfortunately, this means more work, but it is only once per
5836	 *       connection. */
5837	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5838	    !(sk && sk_listener(sk)))
5839		return NF_ACCEPT;
5840#endif
5841
5842	family = state->pf;
5843	if (sk == NULL) {
5844		/* Without an associated socket the packet is either coming
5845		 * from the kernel or it is being forwarded; check the packet
5846		 * to determine which and if the packet is being forwarded
5847		 * query the packet directly to determine the security label. */
5848		if (skb->skb_iif) {
5849			secmark_perm = PACKET__FORWARD_OUT;
5850			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5851				return NF_DROP;
5852		} else {
5853			secmark_perm = PACKET__SEND;
5854			peer_sid = SECINITSID_KERNEL;
5855		}
5856	} else if (sk_listener(sk)) {
5857		/* Locally generated packet but the associated socket is in the
5858		 * listening state which means this is a SYN-ACK packet.  In
5859		 * this particular case the correct security label is assigned
5860		 * to the connection/request_sock but unfortunately we can't
5861		 * query the request_sock as it isn't queued on the parent
5862		 * socket until after the SYN-ACK packet is sent; the only
5863		 * viable choice is to regenerate the label like we do in
5864		 * selinux_inet_conn_request().  See also selinux_ip_output()
5865		 * for similar problems. */
5866		u32 skb_sid;
5867		struct sk_security_struct *sksec;
5868
5869		sksec = sk->sk_security;
5870		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5871			return NF_DROP;
5872		/* At this point, if the returned skb peerlbl is SECSID_NULL
5873		 * and the packet has been through at least one XFRM
5874		 * transformation then we must be dealing with the "final"
5875		 * form of labeled IPsec packet; since we've already applied
5876		 * all of our access controls on this packet we can safely
5877		 * pass the packet. */
5878		if (skb_sid == SECSID_NULL) {
5879			switch (family) {
5880			case PF_INET:
5881				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5882					return NF_ACCEPT;
5883				break;
5884			case PF_INET6:
5885				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5886					return NF_ACCEPT;
5887				break;
5888			default:
5889				return NF_DROP_ERR(-ECONNREFUSED);
5890			}
5891		}
5892		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5893			return NF_DROP;
5894		secmark_perm = PACKET__SEND;
5895	} else {
5896		/* Locally generated packet, fetch the security label from the
5897		 * associated socket. */
5898		struct sk_security_struct *sksec = sk->sk_security;
5899		peer_sid = sksec->sid;
5900		secmark_perm = PACKET__SEND;
5901	}
5902
5903	ifindex = state->out->ifindex;
5904	ad_net_init_from_iif(&ad, &net, ifindex, family);
 
 
5905	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5906		return NF_DROP;
5907
5908	if (secmark_active)
5909		if (avc_has_perm(peer_sid, skb->secmark,
 
5910				 SECCLASS_PACKET, secmark_perm, &ad))
5911			return NF_DROP_ERR(-ECONNREFUSED);
5912
5913	if (peerlbl_active) {
5914		u32 if_sid;
5915		u32 node_sid;
5916
5917		if (sel_netif_sid(state->net, ifindex, &if_sid))
5918			return NF_DROP;
5919		if (avc_has_perm(peer_sid, if_sid,
 
5920				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5921			return NF_DROP_ERR(-ECONNREFUSED);
5922
5923		if (sel_netnode_sid(addrp, family, &node_sid))
5924			return NF_DROP;
5925		if (avc_has_perm(peer_sid, node_sid,
 
5926				 SECCLASS_NODE, NODE__SENDTO, &ad))
5927			return NF_DROP_ERR(-ECONNREFUSED);
5928	}
5929
5930	return NF_ACCEPT;
5931}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5932#endif	/* CONFIG_NETFILTER */
5933
5934static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5935{
5936	int rc = 0;
5937	unsigned int msg_len;
5938	unsigned int data_len = skb->len;
5939	unsigned char *data = skb->data;
5940	struct nlmsghdr *nlh;
5941	struct sk_security_struct *sksec = sk->sk_security;
5942	u16 sclass = sksec->sclass;
5943	u32 perm;
5944
5945	while (data_len >= nlmsg_total_size(0)) {
5946		nlh = (struct nlmsghdr *)data;
5947
5948		/* NOTE: the nlmsg_len field isn't reliably set by some netlink
5949		 *       users which means we can't reject skb's with bogus
5950		 *       length fields; our solution is to follow what
5951		 *       netlink_rcv_skb() does and simply skip processing at
5952		 *       messages with length fields that are clearly junk
5953		 */
5954		if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5955			return 0;
5956
5957		rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5958		if (rc == 0) {
5959			rc = sock_has_perm(sk, perm);
5960			if (rc)
5961				return rc;
5962		} else if (rc == -EINVAL) {
5963			/* -EINVAL is a missing msg/perm mapping */
5964			pr_warn_ratelimited("SELinux: unrecognized netlink"
5965				" message: protocol=%hu nlmsg_type=%hu sclass=%s"
5966				" pid=%d comm=%s\n",
5967				sk->sk_protocol, nlh->nlmsg_type,
5968				secclass_map[sclass - 1].name,
5969				task_pid_nr(current), current->comm);
5970			if (enforcing_enabled() &&
5971			    !security_get_allow_unknown())
5972				return rc;
5973			rc = 0;
5974		} else if (rc == -ENOENT) {
5975			/* -ENOENT is a missing socket/class mapping, ignore */
5976			rc = 0;
5977		} else {
5978			return rc;
5979		}
5980
5981		/* move to the next message after applying netlink padding */
5982		msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5983		if (msg_len >= data_len)
5984			return 0;
5985		data_len -= msg_len;
5986		data += msg_len;
5987	}
5988
5989	return rc;
5990}
5991
5992static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5993{
5994	isec->sclass = sclass;
5995	isec->sid = current_sid();
5996}
5997
5998static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5999			u32 perms)
6000{
6001	struct ipc_security_struct *isec;
6002	struct common_audit_data ad;
6003	u32 sid = current_sid();
6004
6005	isec = selinux_ipc(ipc_perms);
6006
6007	ad.type = LSM_AUDIT_DATA_IPC;
6008	ad.u.ipc_id = ipc_perms->key;
6009
6010	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
 
6011}
6012
6013static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6014{
6015	struct msg_security_struct *msec;
6016
6017	msec = selinux_msg_msg(msg);
6018	msec->sid = SECINITSID_UNLABELED;
6019
6020	return 0;
6021}
6022
6023/* message queue security operations */
6024static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6025{
6026	struct ipc_security_struct *isec;
6027	struct common_audit_data ad;
6028	u32 sid = current_sid();
 
6029
6030	isec = selinux_ipc(msq);
6031	ipc_init_security(isec, SECCLASS_MSGQ);
6032
6033	ad.type = LSM_AUDIT_DATA_IPC;
6034	ad.u.ipc_id = msq->key;
6035
6036	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6037			    MSGQ__CREATE, &ad);
 
 
6038}
6039
6040static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6041{
6042	struct ipc_security_struct *isec;
6043	struct common_audit_data ad;
6044	u32 sid = current_sid();
6045
6046	isec = selinux_ipc(msq);
6047
6048	ad.type = LSM_AUDIT_DATA_IPC;
6049	ad.u.ipc_id = msq->key;
6050
6051	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
 
6052			    MSGQ__ASSOCIATE, &ad);
6053}
6054
6055static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6056{
6057	u32 perms;
 
6058
6059	switch (cmd) {
6060	case IPC_INFO:
6061	case MSG_INFO:
6062		/* No specific object, just general system-wide information. */
6063		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
 
6064				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6065	case IPC_STAT:
6066	case MSG_STAT:
6067	case MSG_STAT_ANY:
6068		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6069		break;
6070	case IPC_SET:
6071		perms = MSGQ__SETATTR;
6072		break;
6073	case IPC_RMID:
6074		perms = MSGQ__DESTROY;
6075		break;
6076	default:
6077		return 0;
6078	}
6079
6080	return ipc_has_perm(msq, perms);
 
6081}
6082
6083static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6084{
6085	struct ipc_security_struct *isec;
6086	struct msg_security_struct *msec;
6087	struct common_audit_data ad;
6088	u32 sid = current_sid();
6089	int rc;
6090
6091	isec = selinux_ipc(msq);
6092	msec = selinux_msg_msg(msg);
6093
6094	/*
6095	 * First time through, need to assign label to the message
6096	 */
6097	if (msec->sid == SECINITSID_UNLABELED) {
6098		/*
6099		 * Compute new sid based on current process and
6100		 * message queue this message will be stored in
6101		 */
6102		rc = security_transition_sid(sid, isec->sid,
6103					     SECCLASS_MSG, NULL, &msec->sid);
6104		if (rc)
6105			return rc;
6106	}
6107
6108	ad.type = LSM_AUDIT_DATA_IPC;
6109	ad.u.ipc_id = msq->key;
6110
6111	/* Can this process write to the queue? */
6112	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
 
6113			  MSGQ__WRITE, &ad);
6114	if (!rc)
6115		/* Can this process send the message */
6116		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
 
6117				  MSG__SEND, &ad);
6118	if (!rc)
6119		/* Can the message be put in the queue? */
6120		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
 
6121				  MSGQ__ENQUEUE, &ad);
6122
6123	return rc;
6124}
6125
6126static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6127				    struct task_struct *target,
6128				    long type, int mode)
6129{
6130	struct ipc_security_struct *isec;
6131	struct msg_security_struct *msec;
6132	struct common_audit_data ad;
6133	u32 sid = task_sid_obj(target);
6134	int rc;
6135
6136	isec = selinux_ipc(msq);
6137	msec = selinux_msg_msg(msg);
6138
6139	ad.type = LSM_AUDIT_DATA_IPC;
6140	ad.u.ipc_id = msq->key;
6141
6142	rc = avc_has_perm(sid, isec->sid,
 
6143			  SECCLASS_MSGQ, MSGQ__READ, &ad);
6144	if (!rc)
6145		rc = avc_has_perm(sid, msec->sid,
 
6146				  SECCLASS_MSG, MSG__RECEIVE, &ad);
6147	return rc;
6148}
6149
6150/* Shared Memory security operations */
6151static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6152{
6153	struct ipc_security_struct *isec;
6154	struct common_audit_data ad;
6155	u32 sid = current_sid();
 
6156
6157	isec = selinux_ipc(shp);
6158	ipc_init_security(isec, SECCLASS_SHM);
6159
6160	ad.type = LSM_AUDIT_DATA_IPC;
6161	ad.u.ipc_id = shp->key;
6162
6163	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6164			    SHM__CREATE, &ad);
 
 
6165}
6166
6167static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6168{
6169	struct ipc_security_struct *isec;
6170	struct common_audit_data ad;
6171	u32 sid = current_sid();
6172
6173	isec = selinux_ipc(shp);
6174
6175	ad.type = LSM_AUDIT_DATA_IPC;
6176	ad.u.ipc_id = shp->key;
6177
6178	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
 
6179			    SHM__ASSOCIATE, &ad);
6180}
6181
6182/* Note, at this point, shp is locked down */
6183static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6184{
6185	u32 perms;
 
6186
6187	switch (cmd) {
6188	case IPC_INFO:
6189	case SHM_INFO:
6190		/* No specific object, just general system-wide information. */
6191		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
 
6192				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6193	case IPC_STAT:
6194	case SHM_STAT:
6195	case SHM_STAT_ANY:
6196		perms = SHM__GETATTR | SHM__ASSOCIATE;
6197		break;
6198	case IPC_SET:
6199		perms = SHM__SETATTR;
6200		break;
6201	case SHM_LOCK:
6202	case SHM_UNLOCK:
6203		perms = SHM__LOCK;
6204		break;
6205	case IPC_RMID:
6206		perms = SHM__DESTROY;
6207		break;
6208	default:
6209		return 0;
6210	}
6211
6212	return ipc_has_perm(shp, perms);
 
6213}
6214
6215static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6216			     char __user *shmaddr, int shmflg)
6217{
6218	u32 perms;
6219
6220	if (shmflg & SHM_RDONLY)
6221		perms = SHM__READ;
6222	else
6223		perms = SHM__READ | SHM__WRITE;
6224
6225	return ipc_has_perm(shp, perms);
6226}
6227
6228/* Semaphore security operations */
6229static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6230{
6231	struct ipc_security_struct *isec;
6232	struct common_audit_data ad;
6233	u32 sid = current_sid();
 
6234
6235	isec = selinux_ipc(sma);
6236	ipc_init_security(isec, SECCLASS_SEM);
6237
6238	ad.type = LSM_AUDIT_DATA_IPC;
6239	ad.u.ipc_id = sma->key;
6240
6241	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6242			    SEM__CREATE, &ad);
 
 
6243}
6244
6245static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6246{
6247	struct ipc_security_struct *isec;
6248	struct common_audit_data ad;
6249	u32 sid = current_sid();
6250
6251	isec = selinux_ipc(sma);
6252
6253	ad.type = LSM_AUDIT_DATA_IPC;
6254	ad.u.ipc_id = sma->key;
6255
6256	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
 
6257			    SEM__ASSOCIATE, &ad);
6258}
6259
6260/* Note, at this point, sma is locked down */
6261static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6262{
6263	int err;
6264	u32 perms;
6265
6266	switch (cmd) {
6267	case IPC_INFO:
6268	case SEM_INFO:
6269		/* No specific object, just general system-wide information. */
6270		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
 
6271				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6272	case GETPID:
6273	case GETNCNT:
6274	case GETZCNT:
6275		perms = SEM__GETATTR;
6276		break;
6277	case GETVAL:
6278	case GETALL:
6279		perms = SEM__READ;
6280		break;
6281	case SETVAL:
6282	case SETALL:
6283		perms = SEM__WRITE;
6284		break;
6285	case IPC_RMID:
6286		perms = SEM__DESTROY;
6287		break;
6288	case IPC_SET:
6289		perms = SEM__SETATTR;
6290		break;
6291	case IPC_STAT:
6292	case SEM_STAT:
6293	case SEM_STAT_ANY:
6294		perms = SEM__GETATTR | SEM__ASSOCIATE;
6295		break;
6296	default:
6297		return 0;
6298	}
6299
6300	err = ipc_has_perm(sma, perms);
6301	return err;
6302}
6303
6304static int selinux_sem_semop(struct kern_ipc_perm *sma,
6305			     struct sembuf *sops, unsigned nsops, int alter)
6306{
6307	u32 perms;
6308
6309	if (alter)
6310		perms = SEM__READ | SEM__WRITE;
6311	else
6312		perms = SEM__READ;
6313
6314	return ipc_has_perm(sma, perms);
6315}
6316
6317static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6318{
6319	u32 av = 0;
6320
6321	av = 0;
6322	if (flag & S_IRUGO)
6323		av |= IPC__UNIX_READ;
6324	if (flag & S_IWUGO)
6325		av |= IPC__UNIX_WRITE;
6326
6327	if (av == 0)
6328		return 0;
6329
6330	return ipc_has_perm(ipcp, av);
6331}
6332
6333static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6334{
6335	struct ipc_security_struct *isec = selinux_ipc(ipcp);
6336	*secid = isec->sid;
6337}
6338
6339static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6340{
6341	if (inode)
6342		inode_doinit_with_dentry(inode, dentry);
6343}
6344
6345static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6346			       char **value)
6347{
6348	const struct task_security_struct *__tsec;
6349	u32 sid;
6350	int error;
6351	unsigned len;
6352
6353	rcu_read_lock();
6354	__tsec = selinux_cred(__task_cred(p));
6355
6356	if (current != p) {
6357		error = avc_has_perm(current_sid(), __tsec->sid,
 
6358				     SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6359		if (error)
6360			goto bad;
6361	}
6362
6363	switch (attr) {
6364	case LSM_ATTR_CURRENT:
6365		sid = __tsec->sid;
6366		break;
6367	case LSM_ATTR_PREV:
6368		sid = __tsec->osid;
6369		break;
6370	case LSM_ATTR_EXEC:
6371		sid = __tsec->exec_sid;
6372		break;
6373	case LSM_ATTR_FSCREATE:
6374		sid = __tsec->create_sid;
6375		break;
6376	case LSM_ATTR_KEYCREATE:
6377		sid = __tsec->keycreate_sid;
6378		break;
6379	case LSM_ATTR_SOCKCREATE:
6380		sid = __tsec->sockcreate_sid;
6381		break;
6382	default:
6383		error = -EOPNOTSUPP;
6384		goto bad;
6385	}
6386	rcu_read_unlock();
6387
6388	if (!sid)
6389		return 0;
6390
6391	error = security_sid_to_context(sid, value, &len);
6392	if (error)
6393		return error;
6394	return len;
6395
6396bad:
6397	rcu_read_unlock();
6398	return error;
6399}
6400
6401static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6402{
6403	struct task_security_struct *tsec;
6404	struct cred *new;
6405	u32 mysid = current_sid(), sid = 0, ptsid;
6406	int error;
6407	char *str = value;
6408
6409	/*
6410	 * Basic control over ability to set these attributes at all.
6411	 */
6412	switch (attr) {
6413	case LSM_ATTR_EXEC:
6414		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6415				     PROCESS__SETEXEC, NULL);
6416		break;
6417	case LSM_ATTR_FSCREATE:
6418		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6419				     PROCESS__SETFSCREATE, NULL);
6420		break;
6421	case LSM_ATTR_KEYCREATE:
6422		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6423				     PROCESS__SETKEYCREATE, NULL);
6424		break;
6425	case LSM_ATTR_SOCKCREATE:
6426		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6427				     PROCESS__SETSOCKCREATE, NULL);
6428		break;
6429	case LSM_ATTR_CURRENT:
6430		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6431				     PROCESS__SETCURRENT, NULL);
6432		break;
6433	default:
6434		error = -EOPNOTSUPP;
6435		break;
6436	}
6437	if (error)
6438		return error;
6439
6440	/* Obtain a SID for the context, if one was specified. */
6441	if (size && str[0] && str[0] != '\n') {
6442		if (str[size-1] == '\n') {
6443			str[size-1] = 0;
6444			size--;
6445		}
6446		error = security_context_to_sid(value, size,
6447						&sid, GFP_KERNEL);
6448		if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6449			if (!has_cap_mac_admin(true)) {
6450				struct audit_buffer *ab;
6451				size_t audit_size;
6452
6453				/* We strip a nul only if it is at the end,
6454				 * otherwise the context contains a nul and
6455				 * we should audit that */
6456				if (str[size - 1] == '\0')
6457					audit_size = size - 1;
6458				else
6459					audit_size = size;
6460				ab = audit_log_start(audit_context(),
6461						     GFP_ATOMIC,
6462						     AUDIT_SELINUX_ERR);
6463				if (!ab)
6464					return error;
6465				audit_log_format(ab, "op=fscreate invalid_context=");
6466				audit_log_n_untrustedstring(ab, value,
6467							    audit_size);
6468				audit_log_end(ab);
6469
6470				return error;
6471			}
6472			error = security_context_to_sid_force(value, size,
6473							&sid);
 
6474		}
6475		if (error)
6476			return error;
6477	}
6478
6479	new = prepare_creds();
6480	if (!new)
6481		return -ENOMEM;
6482
6483	/* Permission checking based on the specified context is
6484	   performed during the actual operation (execve,
6485	   open/mkdir/...), when we know the full context of the
6486	   operation.  See selinux_bprm_creds_for_exec for the execve
6487	   checks and may_create for the file creation checks. The
6488	   operation will then fail if the context is not permitted. */
6489	tsec = selinux_cred(new);
6490	if (attr == LSM_ATTR_EXEC) {
6491		tsec->exec_sid = sid;
6492	} else if (attr == LSM_ATTR_FSCREATE) {
6493		tsec->create_sid = sid;
6494	} else if (attr == LSM_ATTR_KEYCREATE) {
6495		if (sid) {
6496			error = avc_has_perm(mysid, sid,
6497					     SECCLASS_KEY, KEY__CREATE, NULL);
6498			if (error)
6499				goto abort_change;
6500		}
6501		tsec->keycreate_sid = sid;
6502	} else if (attr == LSM_ATTR_SOCKCREATE) {
6503		tsec->sockcreate_sid = sid;
6504	} else if (attr == LSM_ATTR_CURRENT) {
6505		error = -EINVAL;
6506		if (sid == 0)
6507			goto abort_change;
6508
 
 
6509		if (!current_is_single_threaded()) {
6510			error = security_bounded_transition(tsec->sid, sid);
 
6511			if (error)
6512				goto abort_change;
6513		}
6514
6515		/* Check permissions for the transition. */
6516		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
 
6517				     PROCESS__DYNTRANSITION, NULL);
6518		if (error)
6519			goto abort_change;
6520
6521		/* Check for ptracing, and update the task SID if ok.
6522		   Otherwise, leave SID unchanged and fail. */
6523		ptsid = ptrace_parent_sid();
6524		if (ptsid != 0) {
6525			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
 
6526					     PROCESS__PTRACE, NULL);
6527			if (error)
6528				goto abort_change;
6529		}
6530
6531		tsec->sid = sid;
6532	} else {
6533		error = -EINVAL;
6534		goto abort_change;
6535	}
6536
6537	commit_creds(new);
6538	return size;
6539
6540abort_change:
6541	abort_creds(new);
6542	return error;
6543}
6544
6545/**
6546 * selinux_getselfattr - Get SELinux current task attributes
6547 * @attr: the requested attribute
6548 * @ctx: buffer to receive the result
6549 * @size: buffer size (input), buffer size used (output)
6550 * @flags: unused
6551 *
6552 * Fill the passed user space @ctx with the details of the requested
6553 * attribute.
6554 *
6555 * Returns the number of attributes on success, an error code otherwise.
6556 * There will only ever be one attribute.
6557 */
6558static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6559			       size_t *size, u32 flags)
6560{
6561	int rc;
6562	char *val = NULL;
6563	int val_len;
6564
6565	val_len = selinux_lsm_getattr(attr, current, &val);
6566	if (val_len < 0)
6567		return val_len;
6568	rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6569	kfree(val);
6570	return (!rc ? 1 : rc);
6571}
6572
6573static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6574			       size_t size, u32 flags)
6575{
6576	int rc;
6577
6578	rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6579	if (rc > 0)
6580		return 0;
6581	return rc;
6582}
6583
6584static int selinux_getprocattr(struct task_struct *p,
6585			       const char *name, char **value)
6586{
6587	unsigned int attr = lsm_name_to_attr(name);
6588	int rc;
6589
6590	if (attr) {
6591		rc = selinux_lsm_getattr(attr, p, value);
6592		if (rc != -EOPNOTSUPP)
6593			return rc;
6594	}
6595
6596	return -EINVAL;
6597}
6598
6599static int selinux_setprocattr(const char *name, void *value, size_t size)
6600{
6601	int attr = lsm_name_to_attr(name);
6602
6603	if (attr)
6604		return selinux_lsm_setattr(attr, value, size);
6605	return -EINVAL;
6606}
6607
6608static int selinux_ismaclabel(const char *name)
6609{
6610	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6611}
6612
6613static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6614{
6615	return security_sid_to_context(secid,
6616				       secdata, seclen);
6617}
6618
6619static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6620{
6621	return security_context_to_sid(secdata, seclen,
6622				       secid, GFP_KERNEL);
6623}
6624
6625static void selinux_release_secctx(char *secdata, u32 seclen)
6626{
6627	kfree(secdata);
6628}
6629
6630static void selinux_inode_invalidate_secctx(struct inode *inode)
6631{
6632	struct inode_security_struct *isec = selinux_inode(inode);
6633
6634	spin_lock(&isec->lock);
6635	isec->initialized = LABEL_INVALID;
6636	spin_unlock(&isec->lock);
6637}
6638
6639/*
6640 *	called with inode->i_mutex locked
6641 */
6642static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6643{
6644	int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6645					   ctx, ctxlen, 0);
6646	/* Do not return error when suppressing label (SBLABEL_MNT not set). */
6647	return rc == -EOPNOTSUPP ? 0 : rc;
6648}
6649
6650/*
6651 *	called with inode->i_mutex locked
6652 */
6653static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6654{
6655	return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6656				     ctx, ctxlen, 0);
6657}
6658
6659static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6660{
6661	int len = 0;
6662	len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6663					XATTR_SELINUX_SUFFIX, ctx, true);
6664	if (len < 0)
6665		return len;
6666	*ctxlen = len;
6667	return 0;
6668}
6669#ifdef CONFIG_KEYS
6670
6671static int selinux_key_alloc(struct key *k, const struct cred *cred,
6672			     unsigned long flags)
6673{
6674	const struct task_security_struct *tsec;
6675	struct key_security_struct *ksec;
6676
6677	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6678	if (!ksec)
6679		return -ENOMEM;
6680
6681	tsec = selinux_cred(cred);
6682	if (tsec->keycreate_sid)
6683		ksec->sid = tsec->keycreate_sid;
6684	else
6685		ksec->sid = tsec->sid;
6686
6687	k->security = ksec;
6688	return 0;
6689}
6690
6691static void selinux_key_free(struct key *k)
6692{
6693	struct key_security_struct *ksec = k->security;
6694
6695	k->security = NULL;
6696	kfree(ksec);
6697}
6698
6699static int selinux_key_permission(key_ref_t key_ref,
6700				  const struct cred *cred,
6701				  enum key_need_perm need_perm)
6702{
6703	struct key *key;
6704	struct key_security_struct *ksec;
6705	u32 perm, sid;
6706
6707	switch (need_perm) {
6708	case KEY_NEED_VIEW:
6709		perm = KEY__VIEW;
6710		break;
6711	case KEY_NEED_READ:
6712		perm = KEY__READ;
6713		break;
6714	case KEY_NEED_WRITE:
6715		perm = KEY__WRITE;
6716		break;
6717	case KEY_NEED_SEARCH:
6718		perm = KEY__SEARCH;
6719		break;
6720	case KEY_NEED_LINK:
6721		perm = KEY__LINK;
6722		break;
6723	case KEY_NEED_SETATTR:
6724		perm = KEY__SETATTR;
6725		break;
6726	case KEY_NEED_UNLINK:
6727	case KEY_SYSADMIN_OVERRIDE:
6728	case KEY_AUTHTOKEN_OVERRIDE:
6729	case KEY_DEFER_PERM_CHECK:
6730		return 0;
6731	default:
6732		WARN_ON(1);
6733		return -EPERM;
6734
6735	}
6736
6737	sid = cred_sid(cred);
6738	key = key_ref_to_ptr(key_ref);
6739	ksec = key->security;
6740
6741	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
 
6742}
6743
6744static int selinux_key_getsecurity(struct key *key, char **_buffer)
6745{
6746	struct key_security_struct *ksec = key->security;
6747	char *context = NULL;
6748	unsigned len;
6749	int rc;
6750
6751	rc = security_sid_to_context(ksec->sid,
6752				     &context, &len);
6753	if (!rc)
6754		rc = len;
6755	*_buffer = context;
6756	return rc;
6757}
6758
6759#ifdef CONFIG_KEY_NOTIFICATIONS
6760static int selinux_watch_key(struct key *key)
6761{
6762	struct key_security_struct *ksec = key->security;
6763	u32 sid = current_sid();
6764
6765	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
 
6766}
6767#endif
6768#endif
6769
6770#ifdef CONFIG_SECURITY_INFINIBAND
6771static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6772{
6773	struct common_audit_data ad;
6774	int err;
6775	u32 sid = 0;
6776	struct ib_security_struct *sec = ib_sec;
6777	struct lsm_ibpkey_audit ibpkey;
6778
6779	err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6780	if (err)
6781		return err;
6782
6783	ad.type = LSM_AUDIT_DATA_IBPKEY;
6784	ibpkey.subnet_prefix = subnet_prefix;
6785	ibpkey.pkey = pkey_val;
6786	ad.u.ibpkey = &ibpkey;
6787	return avc_has_perm(sec->sid, sid,
 
6788			    SECCLASS_INFINIBAND_PKEY,
6789			    INFINIBAND_PKEY__ACCESS, &ad);
6790}
6791
6792static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6793					    u8 port_num)
6794{
6795	struct common_audit_data ad;
6796	int err;
6797	u32 sid = 0;
6798	struct ib_security_struct *sec = ib_sec;
6799	struct lsm_ibendport_audit ibendport;
6800
6801	err = security_ib_endport_sid(dev_name, port_num,
6802				      &sid);
6803
6804	if (err)
6805		return err;
6806
6807	ad.type = LSM_AUDIT_DATA_IBENDPORT;
6808	ibendport.dev_name = dev_name;
6809	ibendport.port = port_num;
6810	ad.u.ibendport = &ibendport;
6811	return avc_has_perm(sec->sid, sid,
 
6812			    SECCLASS_INFINIBAND_ENDPORT,
6813			    INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6814}
6815
6816static int selinux_ib_alloc_security(void **ib_sec)
6817{
6818	struct ib_security_struct *sec;
6819
6820	sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6821	if (!sec)
6822		return -ENOMEM;
6823	sec->sid = current_sid();
6824
6825	*ib_sec = sec;
6826	return 0;
6827}
6828
6829static void selinux_ib_free_security(void *ib_sec)
6830{
6831	kfree(ib_sec);
6832}
6833#endif
6834
6835#ifdef CONFIG_BPF_SYSCALL
6836static int selinux_bpf(int cmd, union bpf_attr *attr,
6837				     unsigned int size)
6838{
6839	u32 sid = current_sid();
6840	int ret;
6841
6842	switch (cmd) {
6843	case BPF_MAP_CREATE:
6844		ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
 
6845				   NULL);
6846		break;
6847	case BPF_PROG_LOAD:
6848		ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
 
6849				   NULL);
6850		break;
6851	default:
6852		ret = 0;
6853		break;
6854	}
6855
6856	return ret;
6857}
6858
6859static u32 bpf_map_fmode_to_av(fmode_t fmode)
6860{
6861	u32 av = 0;
6862
6863	if (fmode & FMODE_READ)
6864		av |= BPF__MAP_READ;
6865	if (fmode & FMODE_WRITE)
6866		av |= BPF__MAP_WRITE;
6867	return av;
6868}
6869
6870/* This function will check the file pass through unix socket or binder to see
6871 * if it is a bpf related object. And apply corresponding checks on the bpf
6872 * object based on the type. The bpf maps and programs, not like other files and
6873 * socket, are using a shared anonymous inode inside the kernel as their inode.
6874 * So checking that inode cannot identify if the process have privilege to
6875 * access the bpf object and that's why we have to add this additional check in
6876 * selinux_file_receive and selinux_binder_transfer_files.
6877 */
6878static int bpf_fd_pass(const struct file *file, u32 sid)
6879{
6880	struct bpf_security_struct *bpfsec;
6881	struct bpf_prog *prog;
6882	struct bpf_map *map;
6883	int ret;
6884
6885	if (file->f_op == &bpf_map_fops) {
6886		map = file->private_data;
6887		bpfsec = map->security;
6888		ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
 
6889				   bpf_map_fmode_to_av(file->f_mode), NULL);
6890		if (ret)
6891			return ret;
6892	} else if (file->f_op == &bpf_prog_fops) {
6893		prog = file->private_data;
6894		bpfsec = prog->aux->security;
6895		ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
 
6896				   BPF__PROG_RUN, NULL);
6897		if (ret)
6898			return ret;
6899	}
6900	return 0;
6901}
6902
6903static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6904{
6905	u32 sid = current_sid();
6906	struct bpf_security_struct *bpfsec;
6907
6908	bpfsec = map->security;
6909	return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
 
6910			    bpf_map_fmode_to_av(fmode), NULL);
6911}
6912
6913static int selinux_bpf_prog(struct bpf_prog *prog)
6914{
6915	u32 sid = current_sid();
6916	struct bpf_security_struct *bpfsec;
6917
6918	bpfsec = prog->aux->security;
6919	return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
 
6920			    BPF__PROG_RUN, NULL);
6921}
6922
6923static int selinux_bpf_map_alloc(struct bpf_map *map)
6924{
6925	struct bpf_security_struct *bpfsec;
6926
6927	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6928	if (!bpfsec)
6929		return -ENOMEM;
6930
6931	bpfsec->sid = current_sid();
6932	map->security = bpfsec;
6933
6934	return 0;
6935}
6936
6937static void selinux_bpf_map_free(struct bpf_map *map)
6938{
6939	struct bpf_security_struct *bpfsec = map->security;
6940
6941	map->security = NULL;
6942	kfree(bpfsec);
6943}
6944
6945static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6946{
6947	struct bpf_security_struct *bpfsec;
6948
6949	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6950	if (!bpfsec)
6951		return -ENOMEM;
6952
6953	bpfsec->sid = current_sid();
6954	aux->security = bpfsec;
6955
6956	return 0;
6957}
6958
6959static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6960{
6961	struct bpf_security_struct *bpfsec = aux->security;
6962
6963	aux->security = NULL;
6964	kfree(bpfsec);
6965}
6966#endif
6967
6968struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6969	.lbs_cred = sizeof(struct task_security_struct),
6970	.lbs_file = sizeof(struct file_security_struct),
6971	.lbs_inode = sizeof(struct inode_security_struct),
6972	.lbs_ipc = sizeof(struct ipc_security_struct),
6973	.lbs_msg_msg = sizeof(struct msg_security_struct),
6974	.lbs_superblock = sizeof(struct superblock_security_struct),
6975	.lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
6976};
6977
6978#ifdef CONFIG_PERF_EVENTS
6979static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6980{
6981	u32 requested, sid = current_sid();
6982
6983	if (type == PERF_SECURITY_OPEN)
6984		requested = PERF_EVENT__OPEN;
6985	else if (type == PERF_SECURITY_CPU)
6986		requested = PERF_EVENT__CPU;
6987	else if (type == PERF_SECURITY_KERNEL)
6988		requested = PERF_EVENT__KERNEL;
6989	else if (type == PERF_SECURITY_TRACEPOINT)
6990		requested = PERF_EVENT__TRACEPOINT;
6991	else
6992		return -EINVAL;
6993
6994	return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
6995			    requested, NULL);
6996}
6997
6998static int selinux_perf_event_alloc(struct perf_event *event)
6999{
7000	struct perf_event_security_struct *perfsec;
7001
7002	perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
7003	if (!perfsec)
7004		return -ENOMEM;
7005
7006	perfsec->sid = current_sid();
7007	event->security = perfsec;
7008
7009	return 0;
7010}
7011
7012static void selinux_perf_event_free(struct perf_event *event)
7013{
7014	struct perf_event_security_struct *perfsec = event->security;
7015
7016	event->security = NULL;
7017	kfree(perfsec);
7018}
7019
7020static int selinux_perf_event_read(struct perf_event *event)
7021{
7022	struct perf_event_security_struct *perfsec = event->security;
7023	u32 sid = current_sid();
7024
7025	return avc_has_perm(sid, perfsec->sid,
7026			    SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7027}
7028
7029static int selinux_perf_event_write(struct perf_event *event)
7030{
7031	struct perf_event_security_struct *perfsec = event->security;
7032	u32 sid = current_sid();
7033
7034	return avc_has_perm(sid, perfsec->sid,
7035			    SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7036}
7037#endif
7038
7039#ifdef CONFIG_IO_URING
7040/**
7041 * selinux_uring_override_creds - check the requested cred override
7042 * @new: the target creds
7043 *
7044 * Check to see if the current task is allowed to override it's credentials
7045 * to service an io_uring operation.
7046 */
7047static int selinux_uring_override_creds(const struct cred *new)
7048{
7049	return avc_has_perm(current_sid(), cred_sid(new),
7050			    SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7051}
7052
7053/**
7054 * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7055 *
7056 * Check to see if the current task is allowed to create a new io_uring
7057 * kernel polling thread.
7058 */
7059static int selinux_uring_sqpoll(void)
7060{
7061	u32 sid = current_sid();
7062
7063	return avc_has_perm(sid, sid,
7064			    SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7065}
7066
7067/**
7068 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7069 * @ioucmd: the io_uring command structure
7070 *
7071 * Check to see if the current domain is allowed to execute an
7072 * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7073 *
7074 */
7075static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7076{
7077	struct file *file = ioucmd->file;
7078	struct inode *inode = file_inode(file);
7079	struct inode_security_struct *isec = selinux_inode(inode);
7080	struct common_audit_data ad;
7081
7082	ad.type = LSM_AUDIT_DATA_FILE;
7083	ad.u.file = file;
7084
7085	return avc_has_perm(current_sid(), isec->sid,
7086			    SECCLASS_IO_URING, IO_URING__CMD, &ad);
7087}
7088#endif /* CONFIG_IO_URING */
7089
7090static const struct lsm_id selinux_lsmid = {
7091	.name = "selinux",
7092	.id = LSM_ID_SELINUX,
7093};
7094
7095/*
7096 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7097 * 1. any hooks that don't belong to (2.) or (3.) below,
7098 * 2. hooks that both access structures allocated by other hooks, and allocate
7099 *    structures that can be later accessed by other hooks (mostly "cloning"
7100 *    hooks),
7101 * 3. hooks that only allocate structures that can be later accessed by other
7102 *    hooks ("allocating" hooks).
7103 *
7104 * Please follow block comment delimiters in the list to keep this order.
 
 
 
 
7105 */
7106static struct security_hook_list selinux_hooks[] __ro_after_init = {
7107	LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7108	LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7109	LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7110	LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7111
7112	LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7113	LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7114	LSM_HOOK_INIT(capget, selinux_capget),
7115	LSM_HOOK_INIT(capset, selinux_capset),
7116	LSM_HOOK_INIT(capable, selinux_capable),
7117	LSM_HOOK_INIT(quotactl, selinux_quotactl),
7118	LSM_HOOK_INIT(quota_on, selinux_quota_on),
7119	LSM_HOOK_INIT(syslog, selinux_syslog),
7120	LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7121
7122	LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7123
7124	LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7125	LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7126	LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7127
 
7128	LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7129	LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7130	LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7131	LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7132	LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7133	LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7134	LSM_HOOK_INIT(sb_mount, selinux_mount),
7135	LSM_HOOK_INIT(sb_umount, selinux_umount),
7136	LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7137	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7138
7139	LSM_HOOK_INIT(move_mount, selinux_move_mount),
7140
7141	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7142	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7143
7144	LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7145	LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7146	LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7147	LSM_HOOK_INIT(inode_create, selinux_inode_create),
7148	LSM_HOOK_INIT(inode_link, selinux_inode_link),
7149	LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7150	LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7151	LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7152	LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7153	LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7154	LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7155	LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7156	LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7157	LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7158	LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7159	LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7160	LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7161	LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7162	LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7163	LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7164	LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7165	LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7166	LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7167	LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7168	LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7169	LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7170	LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7171	LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7172	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7173	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7174	LSM_HOOK_INIT(path_notify, selinux_path_notify),
7175
7176	LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7177
7178	LSM_HOOK_INIT(file_permission, selinux_file_permission),
7179	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7180	LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7181	LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7182	LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7183	LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7184	LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7185	LSM_HOOK_INIT(file_lock, selinux_file_lock),
7186	LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7187	LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7188	LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7189	LSM_HOOK_INIT(file_receive, selinux_file_receive),
7190
7191	LSM_HOOK_INIT(file_open, selinux_file_open),
7192
7193	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7194	LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7195	LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7196	LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7197	LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7198	LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7199	LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7200	LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7201	LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7202	LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7203	LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7204	LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7205	LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj),
7206	LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj),
7207	LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7208	LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7209	LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7210	LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7211	LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7212	LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7213	LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7214	LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7215	LSM_HOOK_INIT(task_kill, selinux_task_kill),
7216	LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7217	LSM_HOOK_INIT(userns_create, selinux_userns_create),
7218
7219	LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7220	LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7221
7222	LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7223	LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7224	LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7225	LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7226
7227	LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7228	LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7229	LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7230
7231	LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7232	LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7233	LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7234
7235	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7236
7237	LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7238	LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7239	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7240	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7241
7242	LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7243	LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7244	LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7245	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7246	LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7247	LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7248
7249	LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7250	LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7251
7252	LSM_HOOK_INIT(socket_create, selinux_socket_create),
7253	LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7254	LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7255	LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7256	LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7257	LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7258	LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7259	LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7260	LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7261	LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7262	LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7263	LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7264	LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7265	LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7266	LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7267	LSM_HOOK_INIT(socket_getpeersec_stream,
7268			selinux_socket_getpeersec_stream),
7269	LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7270	LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7271	LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7272	LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7273	LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7274	LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7275	LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7276	LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7277	LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7278	LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7279	LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7280	LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7281	LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7282	LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7283	LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7284	LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7285	LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7286	LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7287	LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7288	LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7289	LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7290	LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7291#ifdef CONFIG_SECURITY_INFINIBAND
7292	LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7293	LSM_HOOK_INIT(ib_endport_manage_subnet,
7294		      selinux_ib_endport_manage_subnet),
7295	LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7296#endif
7297#ifdef CONFIG_SECURITY_NETWORK_XFRM
7298	LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7299	LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7300	LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7301	LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7302	LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7303	LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7304			selinux_xfrm_state_pol_flow_match),
7305	LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7306#endif
7307
7308#ifdef CONFIG_KEYS
7309	LSM_HOOK_INIT(key_free, selinux_key_free),
7310	LSM_HOOK_INIT(key_permission, selinux_key_permission),
7311	LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7312#ifdef CONFIG_KEY_NOTIFICATIONS
7313	LSM_HOOK_INIT(watch_key, selinux_watch_key),
7314#endif
7315#endif
7316
7317#ifdef CONFIG_AUDIT
7318	LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7319	LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7320	LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7321#endif
7322
7323#ifdef CONFIG_BPF_SYSCALL
7324	LSM_HOOK_INIT(bpf, selinux_bpf),
7325	LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7326	LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7327	LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7328	LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7329#endif
7330
7331#ifdef CONFIG_PERF_EVENTS
7332	LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7333	LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7334	LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7335	LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7336#endif
7337
7338#ifdef CONFIG_IO_URING
7339	LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7340	LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7341	LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7342#endif
7343
7344	/*
7345	 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7346	 */
7347	LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7348	LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7349	LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7350	LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
 
7351#ifdef CONFIG_SECURITY_NETWORK_XFRM
7352	LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7353#endif
7354
7355	/*
7356	 * PUT "ALLOCATING" HOOKS HERE
7357	 */
7358	LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7359	LSM_HOOK_INIT(msg_queue_alloc_security,
7360		      selinux_msg_queue_alloc_security),
7361	LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7362	LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7363	LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7364	LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7365	LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7366	LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7367	LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7368	LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7369#ifdef CONFIG_SECURITY_INFINIBAND
7370	LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7371#endif
7372#ifdef CONFIG_SECURITY_NETWORK_XFRM
7373	LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7374	LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7375	LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7376		      selinux_xfrm_state_alloc_acquire),
7377#endif
7378#ifdef CONFIG_KEYS
7379	LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7380#endif
7381#ifdef CONFIG_AUDIT
7382	LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7383#endif
7384#ifdef CONFIG_BPF_SYSCALL
7385	LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7386	LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7387#endif
7388#ifdef CONFIG_PERF_EVENTS
7389	LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7390#endif
7391};
7392
7393static __init int selinux_init(void)
7394{
7395	pr_info("SELinux:  Initializing.\n");
7396
7397	memset(&selinux_state, 0, sizeof(selinux_state));
7398	enforcing_set(selinux_enforcing_boot);
7399	selinux_avc_init();
 
 
7400	mutex_init(&selinux_state.status_lock);
7401	mutex_init(&selinux_state.policy_mutex);
7402
7403	/* Set the security state for the initial task. */
7404	cred_init_security();
7405
7406	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7407	if (!default_noexec)
7408		pr_notice("SELinux:  virtual memory is executable by default\n");
7409
7410	avc_init();
7411
7412	avtab_cache_init();
7413
7414	ebitmap_cache_init();
7415
7416	hashtab_cache_init();
7417
7418	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7419			   &selinux_lsmid);
7420
7421	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7422		panic("SELinux: Unable to register AVC netcache callback\n");
7423
7424	if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7425		panic("SELinux: Unable to register AVC LSM notifier callback\n");
7426
7427	if (selinux_enforcing_boot)
7428		pr_debug("SELinux:  Starting in enforcing mode\n");
7429	else
7430		pr_debug("SELinux:  Starting in permissive mode\n");
7431
7432	fs_validate_description("selinux", selinux_fs_parameters);
7433
7434	return 0;
7435}
7436
7437static void delayed_superblock_init(struct super_block *sb, void *unused)
7438{
7439	selinux_set_mnt_opts(sb, NULL, 0, NULL);
7440}
7441
7442void selinux_complete_init(void)
7443{
7444	pr_debug("SELinux:  Completing initialization.\n");
7445
7446	/* Set up any superblocks initialized prior to the policy load. */
7447	pr_debug("SELinux:  Setting up existing superblocks.\n");
7448	iterate_supers(delayed_superblock_init, NULL);
7449}
7450
7451/* SELinux requires early initialization in order to label
7452   all processes and objects when they are created. */
7453DEFINE_LSM(selinux) = {
7454	.name = "selinux",
7455	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7456	.enabled = &selinux_enabled_boot,
7457	.blobs = &selinux_blob_sizes,
7458	.init = selinux_init,
7459};
7460
7461#if defined(CONFIG_NETFILTER)
 
7462static const struct nf_hook_ops selinux_nf_ops[] = {
7463	{
7464		.hook =		selinux_ip_postroute,
7465		.pf =		NFPROTO_IPV4,
7466		.hooknum =	NF_INET_POST_ROUTING,
7467		.priority =	NF_IP_PRI_SELINUX_LAST,
7468	},
7469	{
7470		.hook =		selinux_ip_forward,
7471		.pf =		NFPROTO_IPV4,
7472		.hooknum =	NF_INET_FORWARD,
7473		.priority =	NF_IP_PRI_SELINUX_FIRST,
7474	},
7475	{
7476		.hook =		selinux_ip_output,
7477		.pf =		NFPROTO_IPV4,
7478		.hooknum =	NF_INET_LOCAL_OUT,
7479		.priority =	NF_IP_PRI_SELINUX_FIRST,
7480	},
7481#if IS_ENABLED(CONFIG_IPV6)
7482	{
7483		.hook =		selinux_ip_postroute,
7484		.pf =		NFPROTO_IPV6,
7485		.hooknum =	NF_INET_POST_ROUTING,
7486		.priority =	NF_IP6_PRI_SELINUX_LAST,
7487	},
7488	{
7489		.hook =		selinux_ip_forward,
7490		.pf =		NFPROTO_IPV6,
7491		.hooknum =	NF_INET_FORWARD,
7492		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7493	},
7494	{
7495		.hook =		selinux_ip_output,
7496		.pf =		NFPROTO_IPV6,
7497		.hooknum =	NF_INET_LOCAL_OUT,
7498		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7499	},
7500#endif	/* IPV6 */
7501};
7502
7503static int __net_init selinux_nf_register(struct net *net)
7504{
7505	return nf_register_net_hooks(net, selinux_nf_ops,
7506				     ARRAY_SIZE(selinux_nf_ops));
7507}
7508
7509static void __net_exit selinux_nf_unregister(struct net *net)
7510{
7511	nf_unregister_net_hooks(net, selinux_nf_ops,
7512				ARRAY_SIZE(selinux_nf_ops));
7513}
7514
7515static struct pernet_operations selinux_net_ops = {
7516	.init = selinux_nf_register,
7517	.exit = selinux_nf_unregister,
7518};
7519
7520static int __init selinux_nf_ip_init(void)
7521{
7522	int err;
7523
7524	if (!selinux_enabled_boot)
7525		return 0;
7526
7527	pr_debug("SELinux:  Registering netfilter hooks\n");
7528
7529	err = register_pernet_subsys(&selinux_net_ops);
7530	if (err)
7531		panic("SELinux: register_pernet_subsys: error %d\n", err);
7532
7533	return 0;
7534}
7535__initcall(selinux_nf_ip_init);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7536#endif /* CONFIG_NETFILTER */
v5.9
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  NSA Security-Enhanced Linux (SELinux) security module
   4 *
   5 *  This file contains the SELinux hook function implementations.
   6 *
   7 *  Authors:  Stephen Smalley, <sds@tycho.nsa.gov>
   8 *	      Chris Vance, <cvance@nai.com>
   9 *	      Wayne Salamon, <wsalamon@nai.com>
  10 *	      James Morris <jmorris@redhat.com>
  11 *
  12 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  13 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  14 *					   Eric Paris <eparis@redhat.com>
  15 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  16 *			    <dgoeddel@trustedcs.com>
  17 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  18 *	Paul Moore <paul@paul-moore.com>
  19 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  20 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
  21 *  Copyright (C) 2016 Mellanox Technologies
  22 */
  23
  24#include <linux/init.h>
  25#include <linux/kd.h>
  26#include <linux/kernel.h>
  27#include <linux/tracehook.h>
  28#include <linux/errno.h>
  29#include <linux/sched/signal.h>
  30#include <linux/sched/task.h>
  31#include <linux/lsm_hooks.h>
  32#include <linux/xattr.h>
  33#include <linux/capability.h>
  34#include <linux/unistd.h>
  35#include <linux/mm.h>
  36#include <linux/mman.h>
  37#include <linux/slab.h>
  38#include <linux/pagemap.h>
  39#include <linux/proc_fs.h>
  40#include <linux/swap.h>
  41#include <linux/spinlock.h>
  42#include <linux/syscalls.h>
  43#include <linux/dcache.h>
  44#include <linux/file.h>
  45#include <linux/fdtable.h>
  46#include <linux/namei.h>
  47#include <linux/mount.h>
  48#include <linux/fs_context.h>
  49#include <linux/fs_parser.h>
  50#include <linux/netfilter_ipv4.h>
  51#include <linux/netfilter_ipv6.h>
  52#include <linux/tty.h>
  53#include <net/icmp.h>
  54#include <net/ip.h>		/* for local_port_range[] */
  55#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
  56#include <net/inet_connection_sock.h>
  57#include <net/net_namespace.h>
  58#include <net/netlabel.h>
  59#include <linux/uaccess.h>
  60#include <asm/ioctls.h>
  61#include <linux/atomic.h>
  62#include <linux/bitops.h>
  63#include <linux/interrupt.h>
  64#include <linux/netdevice.h>	/* for network interface checks */
  65#include <net/netlink.h>
  66#include <linux/tcp.h>
  67#include <linux/udp.h>
  68#include <linux/dccp.h>
  69#include <linux/sctp.h>
  70#include <net/sctp/structs.h>
  71#include <linux/quota.h>
  72#include <linux/un.h>		/* for Unix socket types */
  73#include <net/af_unix.h>	/* for Unix socket types */
  74#include <linux/parser.h>
  75#include <linux/nfs_mount.h>
  76#include <net/ipv6.h>
  77#include <linux/hugetlb.h>
  78#include <linux/personality.h>
  79#include <linux/audit.h>
  80#include <linux/string.h>
  81#include <linux/mutex.h>
  82#include <linux/posix-timers.h>
  83#include <linux/syslog.h>
  84#include <linux/user_namespace.h>
  85#include <linux/export.h>
  86#include <linux/msg.h>
  87#include <linux/shm.h>
 
  88#include <linux/bpf.h>
  89#include <linux/kernfs.h>
  90#include <linux/stringhash.h>	/* for hashlen_string() */
  91#include <uapi/linux/mount.h>
  92#include <linux/fsnotify.h>
  93#include <linux/fanotify.h>
 
 
  94
  95#include "avc.h"
  96#include "objsec.h"
  97#include "netif.h"
  98#include "netnode.h"
  99#include "netport.h"
 100#include "ibpkey.h"
 101#include "xfrm.h"
 102#include "netlabel.h"
 103#include "audit.h"
 104#include "avc_ss.h"
 105
 
 
 106struct selinux_state selinux_state;
 107
 108/* SECMARK reference count */
 109static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 110
 111#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 112static int selinux_enforcing_boot __initdata;
 113
 114static int __init enforcing_setup(char *str)
 115{
 116	unsigned long enforcing;
 117	if (!kstrtoul(str, 0, &enforcing))
 118		selinux_enforcing_boot = enforcing ? 1 : 0;
 119	return 1;
 120}
 121__setup("enforcing=", enforcing_setup);
 122#else
 123#define selinux_enforcing_boot 1
 124#endif
 125
 126int selinux_enabled_boot __initdata = 1;
 127#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 128static int __init selinux_enabled_setup(char *str)
 129{
 130	unsigned long enabled;
 131	if (!kstrtoul(str, 0, &enabled))
 132		selinux_enabled_boot = enabled ? 1 : 0;
 133	return 1;
 134}
 135__setup("selinux=", selinux_enabled_setup);
 136#endif
 137
 138static unsigned int selinux_checkreqprot_boot =
 139	CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
 140
 141static int __init checkreqprot_setup(char *str)
 142{
 143	unsigned long checkreqprot;
 144
 145	if (!kstrtoul(str, 0, &checkreqprot)) {
 146		selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
 147		if (checkreqprot)
 148			pr_warn("SELinux: checkreqprot set to 1 via kernel parameter.  This is deprecated and will be rejected in a future kernel release.\n");
 149	}
 150	return 1;
 151}
 152__setup("checkreqprot=", checkreqprot_setup);
 153
 154/**
 155 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 156 *
 157 * Description:
 158 * This function checks the SECMARK reference counter to see if any SECMARK
 159 * targets are currently configured, if the reference counter is greater than
 160 * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 161 * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 162 * policy capability is enabled, SECMARK is always considered enabled.
 163 *
 164 */
 165static int selinux_secmark_enabled(void)
 166{
 167	return (selinux_policycap_alwaysnetwork() ||
 168		atomic_read(&selinux_secmark_refcount));
 169}
 170
 171/**
 172 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 173 *
 174 * Description:
 175 * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 176 * (1) if any are enabled or false (0) if neither are enabled.  If the
 177 * always_check_network policy capability is enabled, peer labeling
 178 * is always considered enabled.
 179 *
 180 */
 181static int selinux_peerlbl_enabled(void)
 182{
 183	return (selinux_policycap_alwaysnetwork() ||
 184		netlbl_enabled() || selinux_xfrm_enabled());
 185}
 186
 187static int selinux_netcache_avc_callback(u32 event)
 188{
 189	if (event == AVC_CALLBACK_RESET) {
 190		sel_netif_flush();
 191		sel_netnode_flush();
 192		sel_netport_flush();
 193		synchronize_net();
 194	}
 195	return 0;
 196}
 197
 198static int selinux_lsm_notifier_avc_callback(u32 event)
 199{
 200	if (event == AVC_CALLBACK_RESET) {
 201		sel_ib_pkey_flush();
 202		call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 203	}
 204
 205	return 0;
 206}
 207
 208/*
 209 * initialise the security for the init task
 210 */
 211static void cred_init_security(void)
 212{
 213	struct cred *cred = (struct cred *) current->real_cred;
 214	struct task_security_struct *tsec;
 215
 216	tsec = selinux_cred(cred);
 217	tsec->osid = tsec->sid = SECINITSID_KERNEL;
 218}
 219
 220/*
 221 * get the security ID of a set of credentials
 222 */
 223static inline u32 cred_sid(const struct cred *cred)
 224{
 225	const struct task_security_struct *tsec;
 226
 227	tsec = selinux_cred(cred);
 228	return tsec->sid;
 229}
 230
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 231/*
 232 * get the objective security ID of a task
 233 */
 234static inline u32 task_sid(const struct task_struct *task)
 235{
 236	u32 sid;
 237
 238	rcu_read_lock();
 239	sid = cred_sid(__task_cred(task));
 240	rcu_read_unlock();
 241	return sid;
 242}
 243
 244static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 245
 246/*
 247 * Try reloading inode security labels that have been marked as invalid.  The
 248 * @may_sleep parameter indicates when sleeping and thus reloading labels is
 249 * allowed; when set to false, returns -ECHILD when the label is
 250 * invalid.  The @dentry parameter should be set to a dentry of the inode.
 251 */
 252static int __inode_security_revalidate(struct inode *inode,
 253				       struct dentry *dentry,
 254				       bool may_sleep)
 255{
 256	struct inode_security_struct *isec = selinux_inode(inode);
 257
 258	might_sleep_if(may_sleep);
 259
 260	if (selinux_initialized(&selinux_state) &&
 261	    isec->initialized != LABEL_INITIALIZED) {
 262		if (!may_sleep)
 263			return -ECHILD;
 264
 265		/*
 266		 * Try reloading the inode security label.  This will fail if
 267		 * @opt_dentry is NULL and no dentry for this inode can be
 268		 * found; in that case, continue using the old label.
 269		 */
 270		inode_doinit_with_dentry(inode, dentry);
 271	}
 272	return 0;
 273}
 274
 275static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 276{
 277	return selinux_inode(inode);
 278}
 279
 280static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 281{
 282	int error;
 283
 284	error = __inode_security_revalidate(inode, NULL, !rcu);
 285	if (error)
 286		return ERR_PTR(error);
 287	return selinux_inode(inode);
 288}
 289
 290/*
 291 * Get the security label of an inode.
 292 */
 293static struct inode_security_struct *inode_security(struct inode *inode)
 294{
 295	__inode_security_revalidate(inode, NULL, true);
 296	return selinux_inode(inode);
 297}
 298
 299static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 300{
 301	struct inode *inode = d_backing_inode(dentry);
 302
 303	return selinux_inode(inode);
 304}
 305
 306/*
 307 * Get the security label of a dentry's backing inode.
 308 */
 309static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 310{
 311	struct inode *inode = d_backing_inode(dentry);
 312
 313	__inode_security_revalidate(inode, dentry, true);
 314	return selinux_inode(inode);
 315}
 316
 317static void inode_free_security(struct inode *inode)
 318{
 319	struct inode_security_struct *isec = selinux_inode(inode);
 320	struct superblock_security_struct *sbsec;
 321
 322	if (!isec)
 323		return;
 324	sbsec = inode->i_sb->s_security;
 325	/*
 326	 * As not all inode security structures are in a list, we check for
 327	 * empty list outside of the lock to make sure that we won't waste
 328	 * time taking a lock doing nothing.
 329	 *
 330	 * The list_del_init() function can be safely called more than once.
 331	 * It should not be possible for this function to be called with
 332	 * concurrent list_add(), but for better safety against future changes
 333	 * in the code, we use list_empty_careful() here.
 334	 */
 335	if (!list_empty_careful(&isec->list)) {
 336		spin_lock(&sbsec->isec_lock);
 337		list_del_init(&isec->list);
 338		spin_unlock(&sbsec->isec_lock);
 339	}
 340}
 341
 342static void superblock_free_security(struct super_block *sb)
 343{
 344	struct superblock_security_struct *sbsec = sb->s_security;
 345	sb->s_security = NULL;
 346	kfree(sbsec);
 347}
 348
 349struct selinux_mnt_opts {
 350	const char *fscontext, *context, *rootcontext, *defcontext;
 
 
 
 351};
 352
 353static void selinux_free_mnt_opts(void *mnt_opts)
 354{
 355	struct selinux_mnt_opts *opts = mnt_opts;
 356	kfree(opts->fscontext);
 357	kfree(opts->context);
 358	kfree(opts->rootcontext);
 359	kfree(opts->defcontext);
 360	kfree(opts);
 361}
 362
 363enum {
 364	Opt_error = -1,
 365	Opt_context = 0,
 366	Opt_defcontext = 1,
 367	Opt_fscontext = 2,
 368	Opt_rootcontext = 3,
 369	Opt_seclabel = 4,
 370};
 371
 372#define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
 373static struct {
 374	const char *name;
 375	int len;
 376	int opt;
 377	bool has_arg;
 378} tokens[] = {
 379	A(context, true),
 380	A(fscontext, true),
 381	A(defcontext, true),
 382	A(rootcontext, true),
 383	A(seclabel, false),
 384};
 385#undef A
 386
 387static int match_opt_prefix(char *s, int l, char **arg)
 388{
 389	int i;
 390
 391	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
 392		size_t len = tokens[i].len;
 393		if (len > l || memcmp(s, tokens[i].name, len))
 394			continue;
 395		if (tokens[i].has_arg) {
 396			if (len == l || s[len] != '=')
 397				continue;
 398			*arg = s + len + 1;
 399		} else if (len != l)
 400			continue;
 401		return tokens[i].opt;
 402	}
 403	return Opt_error;
 404}
 405
 406#define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 407
 408static int may_context_mount_sb_relabel(u32 sid,
 409			struct superblock_security_struct *sbsec,
 410			const struct cred *cred)
 411{
 412	const struct task_security_struct *tsec = selinux_cred(cred);
 413	int rc;
 414
 415	rc = avc_has_perm(&selinux_state,
 416			  tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 417			  FILESYSTEM__RELABELFROM, NULL);
 418	if (rc)
 419		return rc;
 420
 421	rc = avc_has_perm(&selinux_state,
 422			  tsec->sid, sid, SECCLASS_FILESYSTEM,
 423			  FILESYSTEM__RELABELTO, NULL);
 424	return rc;
 425}
 426
 427static int may_context_mount_inode_relabel(u32 sid,
 428			struct superblock_security_struct *sbsec,
 429			const struct cred *cred)
 430{
 431	const struct task_security_struct *tsec = selinux_cred(cred);
 432	int rc;
 433	rc = avc_has_perm(&selinux_state,
 434			  tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 435			  FILESYSTEM__RELABELFROM, NULL);
 436	if (rc)
 437		return rc;
 438
 439	rc = avc_has_perm(&selinux_state,
 440			  sid, sbsec->sid, SECCLASS_FILESYSTEM,
 441			  FILESYSTEM__ASSOCIATE, NULL);
 442	return rc;
 443}
 444
 445static int selinux_is_genfs_special_handling(struct super_block *sb)
 446{
 447	/* Special handling. Genfs but also in-core setxattr handler */
 448	return	!strcmp(sb->s_type->name, "sysfs") ||
 449		!strcmp(sb->s_type->name, "pstore") ||
 450		!strcmp(sb->s_type->name, "debugfs") ||
 451		!strcmp(sb->s_type->name, "tracefs") ||
 452		!strcmp(sb->s_type->name, "rootfs") ||
 453		(selinux_policycap_cgroupseclabel() &&
 454		 (!strcmp(sb->s_type->name, "cgroup") ||
 455		  !strcmp(sb->s_type->name, "cgroup2")));
 456}
 457
 458static int selinux_is_sblabel_mnt(struct super_block *sb)
 459{
 460	struct superblock_security_struct *sbsec = sb->s_security;
 461
 462	/*
 463	 * IMPORTANT: Double-check logic in this function when adding a new
 464	 * SECURITY_FS_USE_* definition!
 465	 */
 466	BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
 467
 468	switch (sbsec->behavior) {
 469	case SECURITY_FS_USE_XATTR:
 470	case SECURITY_FS_USE_TRANS:
 471	case SECURITY_FS_USE_TASK:
 472	case SECURITY_FS_USE_NATIVE:
 473		return 1;
 474
 475	case SECURITY_FS_USE_GENFS:
 476		return selinux_is_genfs_special_handling(sb);
 477
 478	/* Never allow relabeling on context mounts */
 479	case SECURITY_FS_USE_MNTPOINT:
 480	case SECURITY_FS_USE_NONE:
 481	default:
 482		return 0;
 483	}
 484}
 485
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 486static int sb_finish_set_opts(struct super_block *sb)
 487{
 488	struct superblock_security_struct *sbsec = sb->s_security;
 489	struct dentry *root = sb->s_root;
 490	struct inode *root_inode = d_backing_inode(root);
 491	int rc = 0;
 492
 493	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 494		/* Make sure that the xattr handler exists and that no
 495		   error other than -ENODATA is returned by getxattr on
 496		   the root directory.  -ENODATA is ok, as this may be
 497		   the first boot of the SELinux kernel before we have
 498		   assigned xattr values to the filesystem. */
 499		if (!(root_inode->i_opflags & IOP_XATTR)) {
 500			pr_warn("SELinux: (dev %s, type %s) has no "
 501			       "xattr support\n", sb->s_id, sb->s_type->name);
 502			rc = -EOPNOTSUPP;
 503			goto out;
 504		}
 505
 506		rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 507		if (rc < 0 && rc != -ENODATA) {
 508			if (rc == -EOPNOTSUPP)
 509				pr_warn("SELinux: (dev %s, type "
 510				       "%s) has no security xattr handler\n",
 511				       sb->s_id, sb->s_type->name);
 512			else
 513				pr_warn("SELinux: (dev %s, type "
 514				       "%s) getxattr errno %d\n", sb->s_id,
 515				       sb->s_type->name, -rc);
 516			goto out;
 517		}
 518	}
 519
 520	sbsec->flags |= SE_SBINITIALIZED;
 521
 522	/*
 523	 * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 524	 * leave the flag untouched because sb_clone_mnt_opts might be handing
 525	 * us a superblock that needs the flag to be cleared.
 526	 */
 527	if (selinux_is_sblabel_mnt(sb))
 528		sbsec->flags |= SBLABEL_MNT;
 529	else
 530		sbsec->flags &= ~SBLABEL_MNT;
 531
 532	/* Initialize the root inode. */
 533	rc = inode_doinit_with_dentry(root_inode, root);
 534
 535	/* Initialize any other inodes associated with the superblock, e.g.
 536	   inodes created prior to initial policy load or inodes created
 537	   during get_sb by a pseudo filesystem that directly
 538	   populates itself. */
 539	spin_lock(&sbsec->isec_lock);
 540	while (!list_empty(&sbsec->isec_head)) {
 541		struct inode_security_struct *isec =
 542				list_first_entry(&sbsec->isec_head,
 543					   struct inode_security_struct, list);
 544		struct inode *inode = isec->inode;
 545		list_del_init(&isec->list);
 546		spin_unlock(&sbsec->isec_lock);
 547		inode = igrab(inode);
 548		if (inode) {
 549			if (!IS_PRIVATE(inode))
 550				inode_doinit_with_dentry(inode, NULL);
 551			iput(inode);
 552		}
 553		spin_lock(&sbsec->isec_lock);
 554	}
 555	spin_unlock(&sbsec->isec_lock);
 556out:
 557	return rc;
 558}
 559
 560static int bad_option(struct superblock_security_struct *sbsec, char flag,
 561		      u32 old_sid, u32 new_sid)
 562{
 563	char mnt_flags = sbsec->flags & SE_MNTMASK;
 564
 565	/* check if the old mount command had the same options */
 566	if (sbsec->flags & SE_SBINITIALIZED)
 567		if (!(sbsec->flags & flag) ||
 568		    (old_sid != new_sid))
 569			return 1;
 570
 571	/* check if we were passed the same options twice,
 572	 * aka someone passed context=a,context=b
 573	 */
 574	if (!(sbsec->flags & SE_SBINITIALIZED))
 575		if (mnt_flags & flag)
 576			return 1;
 577	return 0;
 578}
 579
 580static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
 581{
 582	int rc = security_context_str_to_sid(&selinux_state, s,
 583					     sid, GFP_KERNEL);
 584	if (rc)
 585		pr_warn("SELinux: security_context_str_to_sid"
 586		       "(%s) failed for (dev %s, type %s) errno=%d\n",
 587		       s, sb->s_id, sb->s_type->name, rc);
 588	return rc;
 589}
 590
 591/*
 592 * Allow filesystems with binary mount data to explicitly set mount point
 593 * labeling information.
 594 */
 595static int selinux_set_mnt_opts(struct super_block *sb,
 596				void *mnt_opts,
 597				unsigned long kern_flags,
 598				unsigned long *set_kern_flags)
 599{
 600	const struct cred *cred = current_cred();
 601	struct superblock_security_struct *sbsec = sb->s_security;
 602	struct dentry *root = sbsec->sb->s_root;
 603	struct selinux_mnt_opts *opts = mnt_opts;
 604	struct inode_security_struct *root_isec;
 605	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 606	u32 defcontext_sid = 0;
 607	int rc = 0;
 608
 
 
 
 
 
 
 
 609	mutex_lock(&sbsec->lock);
 610
 611	if (!selinux_initialized(&selinux_state)) {
 612		if (!opts) {
 613			/* Defer initialization until selinux_complete_init,
 614			   after the initial policy is loaded and the security
 615			   server is ready to handle calls. */
 
 
 
 
 616			goto out;
 617		}
 618		rc = -EINVAL;
 619		pr_warn("SELinux: Unable to set superblock options "
 620			"before the security server is initialized\n");
 621		goto out;
 622	}
 623	if (kern_flags && !set_kern_flags) {
 624		/* Specifying internal flags without providing a place to
 625		 * place the results is not allowed */
 626		rc = -EINVAL;
 627		goto out;
 628	}
 629
 630	/*
 631	 * Binary mount data FS will come through this function twice.  Once
 632	 * from an explicit call and once from the generic calls from the vfs.
 633	 * Since the generic VFS calls will not contain any security mount data
 634	 * we need to skip the double mount verification.
 635	 *
 636	 * This does open a hole in which we will not notice if the first
 637	 * mount using this sb set explict options and a second mount using
 638	 * this sb does not set any security options.  (The first options
 639	 * will be used for both mounts)
 640	 */
 641	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 642	    && !opts)
 643		goto out;
 644
 645	root_isec = backing_inode_security_novalidate(root);
 646
 647	/*
 648	 * parse the mount options, check if they are valid sids.
 649	 * also check if someone is trying to mount the same sb more
 650	 * than once with different security options.
 651	 */
 652	if (opts) {
 653		if (opts->fscontext) {
 654			rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
 655			if (rc)
 656				goto out;
 657			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 658					fscontext_sid))
 659				goto out_double_mount;
 660			sbsec->flags |= FSCONTEXT_MNT;
 661		}
 662		if (opts->context) {
 663			rc = parse_sid(sb, opts->context, &context_sid);
 664			if (rc)
 665				goto out;
 666			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 667					context_sid))
 668				goto out_double_mount;
 669			sbsec->flags |= CONTEXT_MNT;
 670		}
 671		if (opts->rootcontext) {
 672			rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
 673			if (rc)
 674				goto out;
 675			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 676					rootcontext_sid))
 677				goto out_double_mount;
 678			sbsec->flags |= ROOTCONTEXT_MNT;
 679		}
 680		if (opts->defcontext) {
 681			rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
 682			if (rc)
 683				goto out;
 684			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 685					defcontext_sid))
 686				goto out_double_mount;
 687			sbsec->flags |= DEFCONTEXT_MNT;
 688		}
 689	}
 690
 691	if (sbsec->flags & SE_SBINITIALIZED) {
 692		/* previously mounted with options, but not on this attempt? */
 693		if ((sbsec->flags & SE_MNTMASK) && !opts)
 694			goto out_double_mount;
 695		rc = 0;
 696		goto out;
 697	}
 698
 699	if (strcmp(sb->s_type->name, "proc") == 0)
 700		sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 701
 702	if (!strcmp(sb->s_type->name, "debugfs") ||
 703	    !strcmp(sb->s_type->name, "tracefs") ||
 704	    !strcmp(sb->s_type->name, "binder") ||
 705	    !strcmp(sb->s_type->name, "bpf") ||
 706	    !strcmp(sb->s_type->name, "pstore"))
 
 707		sbsec->flags |= SE_SBGENFS;
 708
 709	if (!strcmp(sb->s_type->name, "sysfs") ||
 710	    !strcmp(sb->s_type->name, "cgroup") ||
 711	    !strcmp(sb->s_type->name, "cgroup2"))
 712		sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
 713
 714	if (!sbsec->behavior) {
 715		/*
 716		 * Determine the labeling behavior to use for this
 717		 * filesystem type.
 718		 */
 719		rc = security_fs_use(&selinux_state, sb);
 720		if (rc) {
 721			pr_warn("%s: security_fs_use(%s) returned %d\n",
 722					__func__, sb->s_type->name, rc);
 723			goto out;
 724		}
 725	}
 726
 727	/*
 728	 * If this is a user namespace mount and the filesystem type is not
 729	 * explicitly whitelisted, then no contexts are allowed on the command
 730	 * line and security labels must be ignored.
 731	 */
 732	if (sb->s_user_ns != &init_user_ns &&
 733	    strcmp(sb->s_type->name, "tmpfs") &&
 734	    strcmp(sb->s_type->name, "ramfs") &&
 735	    strcmp(sb->s_type->name, "devpts")) {
 
 736		if (context_sid || fscontext_sid || rootcontext_sid ||
 737		    defcontext_sid) {
 738			rc = -EACCES;
 739			goto out;
 740		}
 741		if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 742			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 743			rc = security_transition_sid(&selinux_state,
 744						     current_sid(),
 745						     current_sid(),
 746						     SECCLASS_FILE, NULL,
 747						     &sbsec->mntpoint_sid);
 748			if (rc)
 749				goto out;
 750		}
 751		goto out_set_opts;
 752	}
 753
 754	/* sets the context of the superblock for the fs being mounted. */
 755	if (fscontext_sid) {
 756		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 757		if (rc)
 758			goto out;
 759
 760		sbsec->sid = fscontext_sid;
 761	}
 762
 763	/*
 764	 * Switch to using mount point labeling behavior.
 765	 * sets the label used on all file below the mountpoint, and will set
 766	 * the superblock context if not already set.
 767	 */
 768	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 
 
 
 
 
 
 
 
 
 
 769		sbsec->behavior = SECURITY_FS_USE_NATIVE;
 770		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 771	}
 772
 773	if (context_sid) {
 774		if (!fscontext_sid) {
 775			rc = may_context_mount_sb_relabel(context_sid, sbsec,
 776							  cred);
 777			if (rc)
 778				goto out;
 779			sbsec->sid = context_sid;
 780		} else {
 781			rc = may_context_mount_inode_relabel(context_sid, sbsec,
 782							     cred);
 783			if (rc)
 784				goto out;
 785		}
 786		if (!rootcontext_sid)
 787			rootcontext_sid = context_sid;
 788
 789		sbsec->mntpoint_sid = context_sid;
 790		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 791	}
 792
 793	if (rootcontext_sid) {
 794		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 795						     cred);
 796		if (rc)
 797			goto out;
 798
 799		root_isec->sid = rootcontext_sid;
 800		root_isec->initialized = LABEL_INITIALIZED;
 801	}
 802
 803	if (defcontext_sid) {
 804		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 805			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 806			rc = -EINVAL;
 807			pr_warn("SELinux: defcontext option is "
 808			       "invalid for this filesystem type\n");
 809			goto out;
 810		}
 811
 812		if (defcontext_sid != sbsec->def_sid) {
 813			rc = may_context_mount_inode_relabel(defcontext_sid,
 814							     sbsec, cred);
 815			if (rc)
 816				goto out;
 817		}
 818
 819		sbsec->def_sid = defcontext_sid;
 820	}
 821
 822out_set_opts:
 823	rc = sb_finish_set_opts(sb);
 824out:
 825	mutex_unlock(&sbsec->lock);
 826	return rc;
 827out_double_mount:
 828	rc = -EINVAL;
 829	pr_warn("SELinux: mount invalid.  Same superblock, different "
 830	       "security settings for (dev %s, type %s)\n", sb->s_id,
 831	       sb->s_type->name);
 832	goto out;
 833}
 834
 835static int selinux_cmp_sb_context(const struct super_block *oldsb,
 836				    const struct super_block *newsb)
 837{
 838	struct superblock_security_struct *old = oldsb->s_security;
 839	struct superblock_security_struct *new = newsb->s_security;
 840	char oldflags = old->flags & SE_MNTMASK;
 841	char newflags = new->flags & SE_MNTMASK;
 842
 843	if (oldflags != newflags)
 844		goto mismatch;
 845	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 846		goto mismatch;
 847	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 848		goto mismatch;
 849	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 850		goto mismatch;
 851	if (oldflags & ROOTCONTEXT_MNT) {
 852		struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 853		struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 854		if (oldroot->sid != newroot->sid)
 855			goto mismatch;
 856	}
 857	return 0;
 858mismatch:
 859	pr_warn("SELinux: mount invalid.  Same superblock, "
 860			    "different security settings for (dev %s, "
 861			    "type %s)\n", newsb->s_id, newsb->s_type->name);
 862	return -EBUSY;
 863}
 864
 865static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 866					struct super_block *newsb,
 867					unsigned long kern_flags,
 868					unsigned long *set_kern_flags)
 869{
 870	int rc = 0;
 871	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 872	struct superblock_security_struct *newsbsec = newsb->s_security;
 
 873
 874	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
 875	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
 876	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
 877
 878	/*
 879	 * if the parent was able to be mounted it clearly had no special lsm
 880	 * mount options.  thus we can safely deal with this superblock later
 881	 */
 882	if (!selinux_initialized(&selinux_state))
 883		return 0;
 884
 885	/*
 886	 * Specifying internal flags without providing a place to
 887	 * place the results is not allowed.
 888	 */
 889	if (kern_flags && !set_kern_flags)
 890		return -EINVAL;
 891
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 892	/* how can we clone if the old one wasn't set up?? */
 893	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 894
 895	/* if fs is reusing a sb, make sure that the contexts match */
 896	if (newsbsec->flags & SE_SBINITIALIZED) {
 
 897		if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
 898			*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 899		return selinux_cmp_sb_context(oldsb, newsb);
 900	}
 901
 902	mutex_lock(&newsbsec->lock);
 903
 904	newsbsec->flags = oldsbsec->flags;
 905
 906	newsbsec->sid = oldsbsec->sid;
 907	newsbsec->def_sid = oldsbsec->def_sid;
 908	newsbsec->behavior = oldsbsec->behavior;
 909
 910	if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
 911		!(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
 912		rc = security_fs_use(&selinux_state, newsb);
 913		if (rc)
 914			goto out;
 915	}
 916
 917	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
 918		newsbsec->behavior = SECURITY_FS_USE_NATIVE;
 919		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 920	}
 921
 922	if (set_context) {
 923		u32 sid = oldsbsec->mntpoint_sid;
 924
 925		if (!set_fscontext)
 926			newsbsec->sid = sid;
 927		if (!set_rootcontext) {
 928			struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 929			newisec->sid = sid;
 930		}
 931		newsbsec->mntpoint_sid = sid;
 932	}
 933	if (set_rootcontext) {
 934		const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
 935		struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 936
 937		newisec->sid = oldisec->sid;
 938	}
 939
 940	sb_finish_set_opts(newsb);
 941out:
 942	mutex_unlock(&newsbsec->lock);
 943	return rc;
 944}
 945
 
 
 
 946static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 947{
 948	struct selinux_mnt_opts *opts = *mnt_opts;
 
 
 949
 950	if (token == Opt_seclabel)	/* eaten and completely ignored */
 
 951		return 0;
 
 
 
 
 
 
 
 952
 953	if (!opts) {
 954		opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
 955		if (!opts)
 956			return -ENOMEM;
 957		*mnt_opts = opts;
 958	}
 959	if (!s)
 960		return -ENOMEM;
 961	switch (token) {
 962	case Opt_context:
 963		if (opts->context || opts->defcontext)
 964			goto Einval;
 965		opts->context = s;
 966		break;
 967	case Opt_fscontext:
 968		if (opts->fscontext)
 969			goto Einval;
 970		opts->fscontext = s;
 971		break;
 972	case Opt_rootcontext:
 973		if (opts->rootcontext)
 974			goto Einval;
 975		opts->rootcontext = s;
 976		break;
 977	case Opt_defcontext:
 978		if (opts->context || opts->defcontext)
 979			goto Einval;
 980		opts->defcontext = s;
 981		break;
 982	}
 983	return 0;
 984Einval:
 985	pr_warn(SEL_MOUNT_FAIL_MSG);
 986	return -EINVAL;
 987}
 988
 989static int selinux_add_mnt_opt(const char *option, const char *val, int len,
 990			       void **mnt_opts)
 991{
 992	int token = Opt_error;
 993	int rc, i;
 994
 995	for (i = 0; i < ARRAY_SIZE(tokens); i++) {
 996		if (strcmp(option, tokens[i].name) == 0) {
 997			token = tokens[i].opt;
 998			break;
 999		}
1000	}
1001
1002	if (token == Opt_error)
1003		return -EINVAL;
1004
1005	if (token != Opt_seclabel) {
1006		val = kmemdup_nul(val, len, GFP_KERNEL);
1007		if (!val) {
1008			rc = -ENOMEM;
1009			goto free_opt;
1010		}
1011	}
1012	rc = selinux_add_opt(token, val, mnt_opts);
1013	if (unlikely(rc)) {
1014		kfree(val);
1015		goto free_opt;
1016	}
 
 
 
 
1017	return rc;
1018
1019free_opt:
1020	if (*mnt_opts) {
1021		selinux_free_mnt_opts(*mnt_opts);
1022		*mnt_opts = NULL;
1023	}
1024	return rc;
1025}
1026
1027static int show_sid(struct seq_file *m, u32 sid)
1028{
1029	char *context = NULL;
1030	u32 len;
1031	int rc;
1032
1033	rc = security_sid_to_context(&selinux_state, sid,
1034					     &context, &len);
1035	if (!rc) {
1036		bool has_comma = context && strchr(context, ',');
1037
1038		seq_putc(m, '=');
1039		if (has_comma)
1040			seq_putc(m, '\"');
1041		seq_escape(m, context, "\"\n\\");
1042		if (has_comma)
1043			seq_putc(m, '\"');
1044	}
1045	kfree(context);
1046	return rc;
1047}
1048
1049static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1050{
1051	struct superblock_security_struct *sbsec = sb->s_security;
1052	int rc;
1053
1054	if (!(sbsec->flags & SE_SBINITIALIZED))
1055		return 0;
1056
1057	if (!selinux_initialized(&selinux_state))
1058		return 0;
1059
1060	if (sbsec->flags & FSCONTEXT_MNT) {
1061		seq_putc(m, ',');
1062		seq_puts(m, FSCONTEXT_STR);
1063		rc = show_sid(m, sbsec->sid);
1064		if (rc)
1065			return rc;
1066	}
1067	if (sbsec->flags & CONTEXT_MNT) {
1068		seq_putc(m, ',');
1069		seq_puts(m, CONTEXT_STR);
1070		rc = show_sid(m, sbsec->mntpoint_sid);
1071		if (rc)
1072			return rc;
1073	}
1074	if (sbsec->flags & DEFCONTEXT_MNT) {
1075		seq_putc(m, ',');
1076		seq_puts(m, DEFCONTEXT_STR);
1077		rc = show_sid(m, sbsec->def_sid);
1078		if (rc)
1079			return rc;
1080	}
1081	if (sbsec->flags & ROOTCONTEXT_MNT) {
1082		struct dentry *root = sbsec->sb->s_root;
1083		struct inode_security_struct *isec = backing_inode_security(root);
1084		seq_putc(m, ',');
1085		seq_puts(m, ROOTCONTEXT_STR);
1086		rc = show_sid(m, isec->sid);
1087		if (rc)
1088			return rc;
1089	}
1090	if (sbsec->flags & SBLABEL_MNT) {
1091		seq_putc(m, ',');
1092		seq_puts(m, SECLABEL_STR);
1093	}
1094	return 0;
1095}
1096
1097static inline u16 inode_mode_to_security_class(umode_t mode)
1098{
1099	switch (mode & S_IFMT) {
1100	case S_IFSOCK:
1101		return SECCLASS_SOCK_FILE;
1102	case S_IFLNK:
1103		return SECCLASS_LNK_FILE;
1104	case S_IFREG:
1105		return SECCLASS_FILE;
1106	case S_IFBLK:
1107		return SECCLASS_BLK_FILE;
1108	case S_IFDIR:
1109		return SECCLASS_DIR;
1110	case S_IFCHR:
1111		return SECCLASS_CHR_FILE;
1112	case S_IFIFO:
1113		return SECCLASS_FIFO_FILE;
1114
1115	}
1116
1117	return SECCLASS_FILE;
1118}
1119
1120static inline int default_protocol_stream(int protocol)
1121{
1122	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
 
1123}
1124
1125static inline int default_protocol_dgram(int protocol)
1126{
1127	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1128}
1129
1130static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1131{
1132	int extsockclass = selinux_policycap_extsockclass();
1133
1134	switch (family) {
1135	case PF_UNIX:
1136		switch (type) {
1137		case SOCK_STREAM:
1138		case SOCK_SEQPACKET:
1139			return SECCLASS_UNIX_STREAM_SOCKET;
1140		case SOCK_DGRAM:
1141		case SOCK_RAW:
1142			return SECCLASS_UNIX_DGRAM_SOCKET;
1143		}
1144		break;
1145	case PF_INET:
1146	case PF_INET6:
1147		switch (type) {
1148		case SOCK_STREAM:
1149		case SOCK_SEQPACKET:
1150			if (default_protocol_stream(protocol))
1151				return SECCLASS_TCP_SOCKET;
1152			else if (extsockclass && protocol == IPPROTO_SCTP)
1153				return SECCLASS_SCTP_SOCKET;
1154			else
1155				return SECCLASS_RAWIP_SOCKET;
1156		case SOCK_DGRAM:
1157			if (default_protocol_dgram(protocol))
1158				return SECCLASS_UDP_SOCKET;
1159			else if (extsockclass && (protocol == IPPROTO_ICMP ||
1160						  protocol == IPPROTO_ICMPV6))
1161				return SECCLASS_ICMP_SOCKET;
1162			else
1163				return SECCLASS_RAWIP_SOCKET;
1164		case SOCK_DCCP:
1165			return SECCLASS_DCCP_SOCKET;
1166		default:
1167			return SECCLASS_RAWIP_SOCKET;
1168		}
1169		break;
1170	case PF_NETLINK:
1171		switch (protocol) {
1172		case NETLINK_ROUTE:
1173			return SECCLASS_NETLINK_ROUTE_SOCKET;
1174		case NETLINK_SOCK_DIAG:
1175			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1176		case NETLINK_NFLOG:
1177			return SECCLASS_NETLINK_NFLOG_SOCKET;
1178		case NETLINK_XFRM:
1179			return SECCLASS_NETLINK_XFRM_SOCKET;
1180		case NETLINK_SELINUX:
1181			return SECCLASS_NETLINK_SELINUX_SOCKET;
1182		case NETLINK_ISCSI:
1183			return SECCLASS_NETLINK_ISCSI_SOCKET;
1184		case NETLINK_AUDIT:
1185			return SECCLASS_NETLINK_AUDIT_SOCKET;
1186		case NETLINK_FIB_LOOKUP:
1187			return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1188		case NETLINK_CONNECTOR:
1189			return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1190		case NETLINK_NETFILTER:
1191			return SECCLASS_NETLINK_NETFILTER_SOCKET;
1192		case NETLINK_DNRTMSG:
1193			return SECCLASS_NETLINK_DNRT_SOCKET;
1194		case NETLINK_KOBJECT_UEVENT:
1195			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1196		case NETLINK_GENERIC:
1197			return SECCLASS_NETLINK_GENERIC_SOCKET;
1198		case NETLINK_SCSITRANSPORT:
1199			return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1200		case NETLINK_RDMA:
1201			return SECCLASS_NETLINK_RDMA_SOCKET;
1202		case NETLINK_CRYPTO:
1203			return SECCLASS_NETLINK_CRYPTO_SOCKET;
1204		default:
1205			return SECCLASS_NETLINK_SOCKET;
1206		}
1207	case PF_PACKET:
1208		return SECCLASS_PACKET_SOCKET;
1209	case PF_KEY:
1210		return SECCLASS_KEY_SOCKET;
1211	case PF_APPLETALK:
1212		return SECCLASS_APPLETALK_SOCKET;
1213	}
1214
1215	if (extsockclass) {
1216		switch (family) {
1217		case PF_AX25:
1218			return SECCLASS_AX25_SOCKET;
1219		case PF_IPX:
1220			return SECCLASS_IPX_SOCKET;
1221		case PF_NETROM:
1222			return SECCLASS_NETROM_SOCKET;
1223		case PF_ATMPVC:
1224			return SECCLASS_ATMPVC_SOCKET;
1225		case PF_X25:
1226			return SECCLASS_X25_SOCKET;
1227		case PF_ROSE:
1228			return SECCLASS_ROSE_SOCKET;
1229		case PF_DECnet:
1230			return SECCLASS_DECNET_SOCKET;
1231		case PF_ATMSVC:
1232			return SECCLASS_ATMSVC_SOCKET;
1233		case PF_RDS:
1234			return SECCLASS_RDS_SOCKET;
1235		case PF_IRDA:
1236			return SECCLASS_IRDA_SOCKET;
1237		case PF_PPPOX:
1238			return SECCLASS_PPPOX_SOCKET;
1239		case PF_LLC:
1240			return SECCLASS_LLC_SOCKET;
1241		case PF_CAN:
1242			return SECCLASS_CAN_SOCKET;
1243		case PF_TIPC:
1244			return SECCLASS_TIPC_SOCKET;
1245		case PF_BLUETOOTH:
1246			return SECCLASS_BLUETOOTH_SOCKET;
1247		case PF_IUCV:
1248			return SECCLASS_IUCV_SOCKET;
1249		case PF_RXRPC:
1250			return SECCLASS_RXRPC_SOCKET;
1251		case PF_ISDN:
1252			return SECCLASS_ISDN_SOCKET;
1253		case PF_PHONET:
1254			return SECCLASS_PHONET_SOCKET;
1255		case PF_IEEE802154:
1256			return SECCLASS_IEEE802154_SOCKET;
1257		case PF_CAIF:
1258			return SECCLASS_CAIF_SOCKET;
1259		case PF_ALG:
1260			return SECCLASS_ALG_SOCKET;
1261		case PF_NFC:
1262			return SECCLASS_NFC_SOCKET;
1263		case PF_VSOCK:
1264			return SECCLASS_VSOCK_SOCKET;
1265		case PF_KCM:
1266			return SECCLASS_KCM_SOCKET;
1267		case PF_QIPCRTR:
1268			return SECCLASS_QIPCRTR_SOCKET;
1269		case PF_SMC:
1270			return SECCLASS_SMC_SOCKET;
1271		case PF_XDP:
1272			return SECCLASS_XDP_SOCKET;
1273#if PF_MAX > 45
 
 
1274#error New address family defined, please update this function.
1275#endif
1276		}
1277	}
1278
1279	return SECCLASS_SOCKET;
1280}
1281
1282static int selinux_genfs_get_sid(struct dentry *dentry,
1283				 u16 tclass,
1284				 u16 flags,
1285				 u32 *sid)
1286{
1287	int rc;
1288	struct super_block *sb = dentry->d_sb;
1289	char *buffer, *path;
1290
1291	buffer = (char *)__get_free_page(GFP_KERNEL);
1292	if (!buffer)
1293		return -ENOMEM;
1294
1295	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1296	if (IS_ERR(path))
1297		rc = PTR_ERR(path);
1298	else {
1299		if (flags & SE_SBPROC) {
1300			/* each process gets a /proc/PID/ entry. Strip off the
1301			 * PID part to get a valid selinux labeling.
1302			 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1303			while (path[1] >= '0' && path[1] <= '9') {
1304				path[1] = '/';
1305				path++;
1306			}
1307		}
1308		rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1309					path, tclass, sid);
1310		if (rc == -ENOENT) {
1311			/* No match in policy, mark as unlabeled. */
1312			*sid = SECINITSID_UNLABELED;
1313			rc = 0;
1314		}
1315	}
1316	free_page((unsigned long)buffer);
1317	return rc;
1318}
1319
1320static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1321				  u32 def_sid, u32 *sid)
1322{
1323#define INITCONTEXTLEN 255
1324	char *context;
1325	unsigned int len;
1326	int rc;
1327
1328	len = INITCONTEXTLEN;
1329	context = kmalloc(len + 1, GFP_NOFS);
1330	if (!context)
1331		return -ENOMEM;
1332
1333	context[len] = '\0';
1334	rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1335	if (rc == -ERANGE) {
1336		kfree(context);
1337
1338		/* Need a larger buffer.  Query for the right size. */
1339		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1340		if (rc < 0)
1341			return rc;
1342
1343		len = rc;
1344		context = kmalloc(len + 1, GFP_NOFS);
1345		if (!context)
1346			return -ENOMEM;
1347
1348		context[len] = '\0';
1349		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1350				    context, len);
1351	}
1352	if (rc < 0) {
1353		kfree(context);
1354		if (rc != -ENODATA) {
1355			pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1356				__func__, -rc, inode->i_sb->s_id, inode->i_ino);
1357			return rc;
1358		}
1359		*sid = def_sid;
1360		return 0;
1361	}
1362
1363	rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
1364					     def_sid, GFP_NOFS);
1365	if (rc) {
1366		char *dev = inode->i_sb->s_id;
1367		unsigned long ino = inode->i_ino;
1368
1369		if (rc == -EINVAL) {
1370			pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s.  This indicates you may need to relabel the inode or the filesystem in question.\n",
1371					      ino, dev, context);
1372		} else {
1373			pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1374				__func__, context, -rc, dev, ino);
1375		}
1376	}
1377	kfree(context);
1378	return 0;
1379}
1380
1381/* The inode's security attributes must be initialized before first use. */
1382static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1383{
1384	struct superblock_security_struct *sbsec = NULL;
1385	struct inode_security_struct *isec = selinux_inode(inode);
1386	u32 task_sid, sid = 0;
1387	u16 sclass;
1388	struct dentry *dentry;
1389	int rc = 0;
1390
1391	if (isec->initialized == LABEL_INITIALIZED)
1392		return 0;
1393
1394	spin_lock(&isec->lock);
1395	if (isec->initialized == LABEL_INITIALIZED)
1396		goto out_unlock;
1397
1398	if (isec->sclass == SECCLASS_FILE)
1399		isec->sclass = inode_mode_to_security_class(inode->i_mode);
1400
1401	sbsec = inode->i_sb->s_security;
1402	if (!(sbsec->flags & SE_SBINITIALIZED)) {
1403		/* Defer initialization until selinux_complete_init,
1404		   after the initial policy is loaded and the security
1405		   server is ready to handle calls. */
1406		spin_lock(&sbsec->isec_lock);
1407		if (list_empty(&isec->list))
1408			list_add(&isec->list, &sbsec->isec_head);
1409		spin_unlock(&sbsec->isec_lock);
1410		goto out_unlock;
1411	}
1412
1413	sclass = isec->sclass;
1414	task_sid = isec->task_sid;
1415	sid = isec->sid;
1416	isec->initialized = LABEL_PENDING;
1417	spin_unlock(&isec->lock);
1418
1419	switch (sbsec->behavior) {
 
 
 
 
1420	case SECURITY_FS_USE_NATIVE:
1421		break;
1422	case SECURITY_FS_USE_XATTR:
1423		if (!(inode->i_opflags & IOP_XATTR)) {
1424			sid = sbsec->def_sid;
1425			break;
1426		}
1427		/* Need a dentry, since the xattr API requires one.
1428		   Life would be simpler if we could just pass the inode. */
1429		if (opt_dentry) {
1430			/* Called from d_instantiate or d_splice_alias. */
1431			dentry = dget(opt_dentry);
1432		} else {
1433			/*
1434			 * Called from selinux_complete_init, try to find a dentry.
1435			 * Some filesystems really want a connected one, so try
1436			 * that first.  We could split SECURITY_FS_USE_XATTR in
1437			 * two, depending upon that...
1438			 */
1439			dentry = d_find_alias(inode);
1440			if (!dentry)
1441				dentry = d_find_any_alias(inode);
1442		}
1443		if (!dentry) {
1444			/*
1445			 * this is can be hit on boot when a file is accessed
1446			 * before the policy is loaded.  When we load policy we
1447			 * may find inodes that have no dentry on the
1448			 * sbsec->isec_head list.  No reason to complain as these
1449			 * will get fixed up the next time we go through
1450			 * inode_doinit with a dentry, before these inodes could
1451			 * be used again by userspace.
1452			 */
1453			goto out;
1454		}
1455
1456		rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1457					    &sid);
1458		dput(dentry);
1459		if (rc)
1460			goto out;
1461		break;
1462	case SECURITY_FS_USE_TASK:
1463		sid = task_sid;
1464		break;
1465	case SECURITY_FS_USE_TRANS:
1466		/* Default to the fs SID. */
1467		sid = sbsec->sid;
1468
1469		/* Try to obtain a transition SID. */
1470		rc = security_transition_sid(&selinux_state, task_sid, sid,
1471					     sclass, NULL, &sid);
1472		if (rc)
1473			goto out;
1474		break;
1475	case SECURITY_FS_USE_MNTPOINT:
1476		sid = sbsec->mntpoint_sid;
1477		break;
1478	default:
1479		/* Default to the fs superblock SID. */
1480		sid = sbsec->sid;
1481
1482		if ((sbsec->flags & SE_SBGENFS) &&
1483		     (!S_ISLNK(inode->i_mode) ||
1484		      selinux_policycap_genfs_seclabel_symlinks())) {
1485			/* We must have a dentry to determine the label on
1486			 * procfs inodes */
1487			if (opt_dentry) {
1488				/* Called from d_instantiate or
1489				 * d_splice_alias. */
1490				dentry = dget(opt_dentry);
1491			} else {
1492				/* Called from selinux_complete_init, try to
1493				 * find a dentry.  Some filesystems really want
1494				 * a connected one, so try that first.
1495				 */
1496				dentry = d_find_alias(inode);
1497				if (!dentry)
1498					dentry = d_find_any_alias(inode);
1499			}
1500			/*
1501			 * This can be hit on boot when a file is accessed
1502			 * before the policy is loaded.  When we load policy we
1503			 * may find inodes that have no dentry on the
1504			 * sbsec->isec_head list.  No reason to complain as
1505			 * these will get fixed up the next time we go through
1506			 * inode_doinit() with a dentry, before these inodes
1507			 * could be used again by userspace.
1508			 */
1509			if (!dentry)
1510				goto out;
1511			rc = selinux_genfs_get_sid(dentry, sclass,
1512						   sbsec->flags, &sid);
1513			if (rc) {
1514				dput(dentry);
1515				goto out;
1516			}
1517
1518			if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1519			    (inode->i_opflags & IOP_XATTR)) {
1520				rc = inode_doinit_use_xattr(inode, dentry,
1521							    sid, &sid);
1522				if (rc) {
1523					dput(dentry);
1524					goto out;
1525				}
1526			}
1527			dput(dentry);
1528		}
1529		break;
1530	}
1531
1532out:
1533	spin_lock(&isec->lock);
1534	if (isec->initialized == LABEL_PENDING) {
1535		if (!sid || rc) {
1536			isec->initialized = LABEL_INVALID;
1537			goto out_unlock;
1538		}
1539
1540		isec->initialized = LABEL_INITIALIZED;
1541		isec->sid = sid;
1542	}
1543
1544out_unlock:
1545	spin_unlock(&isec->lock);
1546	return rc;
 
 
 
 
 
 
 
 
 
1547}
1548
1549/* Convert a Linux signal to an access vector. */
1550static inline u32 signal_to_av(int sig)
1551{
1552	u32 perm = 0;
1553
1554	switch (sig) {
1555	case SIGCHLD:
1556		/* Commonly granted from child to parent. */
1557		perm = PROCESS__SIGCHLD;
1558		break;
1559	case SIGKILL:
1560		/* Cannot be caught or ignored */
1561		perm = PROCESS__SIGKILL;
1562		break;
1563	case SIGSTOP:
1564		/* Cannot be caught or ignored */
1565		perm = PROCESS__SIGSTOP;
1566		break;
1567	default:
1568		/* All other signals. */
1569		perm = PROCESS__SIGNAL;
1570		break;
1571	}
1572
1573	return perm;
1574}
1575
1576#if CAP_LAST_CAP > 63
1577#error Fix SELinux to handle capabilities > 63.
1578#endif
1579
1580/* Check whether a task is allowed to use a capability. */
1581static int cred_has_capability(const struct cred *cred,
1582			       int cap, unsigned int opts, bool initns)
1583{
1584	struct common_audit_data ad;
1585	struct av_decision avd;
1586	u16 sclass;
1587	u32 sid = cred_sid(cred);
1588	u32 av = CAP_TO_MASK(cap);
1589	int rc;
1590
1591	ad.type = LSM_AUDIT_DATA_CAP;
1592	ad.u.cap = cap;
1593
1594	switch (CAP_TO_INDEX(cap)) {
1595	case 0:
1596		sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1597		break;
1598	case 1:
1599		sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1600		break;
1601	default:
1602		pr_err("SELinux:  out of range capability %d\n", cap);
1603		BUG();
1604		return -EINVAL;
1605	}
1606
1607	rc = avc_has_perm_noaudit(&selinux_state,
1608				  sid, sid, sclass, av, 0, &avd);
1609	if (!(opts & CAP_OPT_NOAUDIT)) {
1610		int rc2 = avc_audit(&selinux_state,
1611				    sid, sid, sclass, av, &avd, rc, &ad, 0);
1612		if (rc2)
1613			return rc2;
1614	}
1615	return rc;
1616}
1617
1618/* Check whether a task has a particular permission to an inode.
1619   The 'adp' parameter is optional and allows other audit
1620   data to be passed (e.g. the dentry). */
1621static int inode_has_perm(const struct cred *cred,
1622			  struct inode *inode,
1623			  u32 perms,
1624			  struct common_audit_data *adp)
1625{
1626	struct inode_security_struct *isec;
1627	u32 sid;
1628
1629	validate_creds(cred);
1630
1631	if (unlikely(IS_PRIVATE(inode)))
1632		return 0;
1633
1634	sid = cred_sid(cred);
1635	isec = selinux_inode(inode);
1636
1637	return avc_has_perm(&selinux_state,
1638			    sid, isec->sid, isec->sclass, perms, adp);
1639}
1640
1641/* Same as inode_has_perm, but pass explicit audit data containing
1642   the dentry to help the auditing code to more easily generate the
1643   pathname if needed. */
1644static inline int dentry_has_perm(const struct cred *cred,
1645				  struct dentry *dentry,
1646				  u32 av)
1647{
1648	struct inode *inode = d_backing_inode(dentry);
1649	struct common_audit_data ad;
1650
1651	ad.type = LSM_AUDIT_DATA_DENTRY;
1652	ad.u.dentry = dentry;
1653	__inode_security_revalidate(inode, dentry, true);
1654	return inode_has_perm(cred, inode, av, &ad);
1655}
1656
1657/* Same as inode_has_perm, but pass explicit audit data containing
1658   the path to help the auditing code to more easily generate the
1659   pathname if needed. */
1660static inline int path_has_perm(const struct cred *cred,
1661				const struct path *path,
1662				u32 av)
1663{
1664	struct inode *inode = d_backing_inode(path->dentry);
1665	struct common_audit_data ad;
1666
1667	ad.type = LSM_AUDIT_DATA_PATH;
1668	ad.u.path = *path;
1669	__inode_security_revalidate(inode, path->dentry, true);
1670	return inode_has_perm(cred, inode, av, &ad);
1671}
1672
1673/* Same as path_has_perm, but uses the inode from the file struct. */
1674static inline int file_path_has_perm(const struct cred *cred,
1675				     struct file *file,
1676				     u32 av)
1677{
1678	struct common_audit_data ad;
1679
1680	ad.type = LSM_AUDIT_DATA_FILE;
1681	ad.u.file = file;
1682	return inode_has_perm(cred, file_inode(file), av, &ad);
1683}
1684
1685#ifdef CONFIG_BPF_SYSCALL
1686static int bpf_fd_pass(struct file *file, u32 sid);
1687#endif
1688
1689/* Check whether a task can use an open file descriptor to
1690   access an inode in a given way.  Check access to the
1691   descriptor itself, and then use dentry_has_perm to
1692   check a particular permission to the file.
1693   Access to the descriptor is implicitly granted if it
1694   has the same SID as the process.  If av is zero, then
1695   access to the file is not checked, e.g. for cases
1696   where only the descriptor is affected like seek. */
1697static int file_has_perm(const struct cred *cred,
1698			 struct file *file,
1699			 u32 av)
1700{
1701	struct file_security_struct *fsec = selinux_file(file);
1702	struct inode *inode = file_inode(file);
1703	struct common_audit_data ad;
1704	u32 sid = cred_sid(cred);
1705	int rc;
1706
1707	ad.type = LSM_AUDIT_DATA_FILE;
1708	ad.u.file = file;
1709
1710	if (sid != fsec->sid) {
1711		rc = avc_has_perm(&selinux_state,
1712				  sid, fsec->sid,
1713				  SECCLASS_FD,
1714				  FD__USE,
1715				  &ad);
1716		if (rc)
1717			goto out;
1718	}
1719
1720#ifdef CONFIG_BPF_SYSCALL
1721	rc = bpf_fd_pass(file, cred_sid(cred));
1722	if (rc)
1723		return rc;
1724#endif
1725
1726	/* av is zero if only checking access to the descriptor. */
1727	rc = 0;
1728	if (av)
1729		rc = inode_has_perm(cred, inode, av, &ad);
1730
1731out:
1732	return rc;
1733}
1734
1735/*
1736 * Determine the label for an inode that might be unioned.
1737 */
1738static int
1739selinux_determine_inode_label(const struct task_security_struct *tsec,
1740				 struct inode *dir,
1741				 const struct qstr *name, u16 tclass,
1742				 u32 *_new_isid)
1743{
1744	const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
 
1745
1746	if ((sbsec->flags & SE_SBINITIALIZED) &&
1747	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1748		*_new_isid = sbsec->mntpoint_sid;
1749	} else if ((sbsec->flags & SBLABEL_MNT) &&
1750		   tsec->create_sid) {
1751		*_new_isid = tsec->create_sid;
1752	} else {
1753		const struct inode_security_struct *dsec = inode_security(dir);
1754		return security_transition_sid(&selinux_state, tsec->sid,
1755					       dsec->sid, tclass,
1756					       name, _new_isid);
1757	}
1758
1759	return 0;
1760}
1761
1762/* Check whether a task can create a file. */
1763static int may_create(struct inode *dir,
1764		      struct dentry *dentry,
1765		      u16 tclass)
1766{
1767	const struct task_security_struct *tsec = selinux_cred(current_cred());
1768	struct inode_security_struct *dsec;
1769	struct superblock_security_struct *sbsec;
1770	u32 sid, newsid;
1771	struct common_audit_data ad;
1772	int rc;
1773
1774	dsec = inode_security(dir);
1775	sbsec = dir->i_sb->s_security;
1776
1777	sid = tsec->sid;
1778
1779	ad.type = LSM_AUDIT_DATA_DENTRY;
1780	ad.u.dentry = dentry;
1781
1782	rc = avc_has_perm(&selinux_state,
1783			  sid, dsec->sid, SECCLASS_DIR,
1784			  DIR__ADD_NAME | DIR__SEARCH,
1785			  &ad);
1786	if (rc)
1787		return rc;
1788
1789	rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1790					   &newsid);
1791	if (rc)
1792		return rc;
1793
1794	rc = avc_has_perm(&selinux_state,
1795			  sid, newsid, tclass, FILE__CREATE, &ad);
1796	if (rc)
1797		return rc;
1798
1799	return avc_has_perm(&selinux_state,
1800			    newsid, sbsec->sid,
1801			    SECCLASS_FILESYSTEM,
1802			    FILESYSTEM__ASSOCIATE, &ad);
1803}
1804
1805#define MAY_LINK	0
1806#define MAY_UNLINK	1
1807#define MAY_RMDIR	2
1808
1809/* Check whether a task can link, unlink, or rmdir a file/directory. */
1810static int may_link(struct inode *dir,
1811		    struct dentry *dentry,
1812		    int kind)
1813
1814{
1815	struct inode_security_struct *dsec, *isec;
1816	struct common_audit_data ad;
1817	u32 sid = current_sid();
1818	u32 av;
1819	int rc;
1820
1821	dsec = inode_security(dir);
1822	isec = backing_inode_security(dentry);
1823
1824	ad.type = LSM_AUDIT_DATA_DENTRY;
1825	ad.u.dentry = dentry;
1826
1827	av = DIR__SEARCH;
1828	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1829	rc = avc_has_perm(&selinux_state,
1830			  sid, dsec->sid, SECCLASS_DIR, av, &ad);
1831	if (rc)
1832		return rc;
1833
1834	switch (kind) {
1835	case MAY_LINK:
1836		av = FILE__LINK;
1837		break;
1838	case MAY_UNLINK:
1839		av = FILE__UNLINK;
1840		break;
1841	case MAY_RMDIR:
1842		av = DIR__RMDIR;
1843		break;
1844	default:
1845		pr_warn("SELinux: %s:  unrecognized kind %d\n",
1846			__func__, kind);
1847		return 0;
1848	}
1849
1850	rc = avc_has_perm(&selinux_state,
1851			  sid, isec->sid, isec->sclass, av, &ad);
1852	return rc;
1853}
1854
1855static inline int may_rename(struct inode *old_dir,
1856			     struct dentry *old_dentry,
1857			     struct inode *new_dir,
1858			     struct dentry *new_dentry)
1859{
1860	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1861	struct common_audit_data ad;
1862	u32 sid = current_sid();
1863	u32 av;
1864	int old_is_dir, new_is_dir;
1865	int rc;
1866
1867	old_dsec = inode_security(old_dir);
1868	old_isec = backing_inode_security(old_dentry);
1869	old_is_dir = d_is_dir(old_dentry);
1870	new_dsec = inode_security(new_dir);
1871
1872	ad.type = LSM_AUDIT_DATA_DENTRY;
1873
1874	ad.u.dentry = old_dentry;
1875	rc = avc_has_perm(&selinux_state,
1876			  sid, old_dsec->sid, SECCLASS_DIR,
1877			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1878	if (rc)
1879		return rc;
1880	rc = avc_has_perm(&selinux_state,
1881			  sid, old_isec->sid,
1882			  old_isec->sclass, FILE__RENAME, &ad);
1883	if (rc)
1884		return rc;
1885	if (old_is_dir && new_dir != old_dir) {
1886		rc = avc_has_perm(&selinux_state,
1887				  sid, old_isec->sid,
1888				  old_isec->sclass, DIR__REPARENT, &ad);
1889		if (rc)
1890			return rc;
1891	}
1892
1893	ad.u.dentry = new_dentry;
1894	av = DIR__ADD_NAME | DIR__SEARCH;
1895	if (d_is_positive(new_dentry))
1896		av |= DIR__REMOVE_NAME;
1897	rc = avc_has_perm(&selinux_state,
1898			  sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1899	if (rc)
1900		return rc;
1901	if (d_is_positive(new_dentry)) {
1902		new_isec = backing_inode_security(new_dentry);
1903		new_is_dir = d_is_dir(new_dentry);
1904		rc = avc_has_perm(&selinux_state,
1905				  sid, new_isec->sid,
1906				  new_isec->sclass,
1907				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1908		if (rc)
1909			return rc;
1910	}
1911
1912	return 0;
1913}
1914
1915/* Check whether a task can perform a filesystem operation. */
1916static int superblock_has_perm(const struct cred *cred,
1917			       struct super_block *sb,
1918			       u32 perms,
1919			       struct common_audit_data *ad)
1920{
1921	struct superblock_security_struct *sbsec;
1922	u32 sid = cred_sid(cred);
1923
1924	sbsec = sb->s_security;
1925	return avc_has_perm(&selinux_state,
1926			    sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1927}
1928
1929/* Convert a Linux mode and permission mask to an access vector. */
1930static inline u32 file_mask_to_av(int mode, int mask)
1931{
1932	u32 av = 0;
1933
1934	if (!S_ISDIR(mode)) {
1935		if (mask & MAY_EXEC)
1936			av |= FILE__EXECUTE;
1937		if (mask & MAY_READ)
1938			av |= FILE__READ;
1939
1940		if (mask & MAY_APPEND)
1941			av |= FILE__APPEND;
1942		else if (mask & MAY_WRITE)
1943			av |= FILE__WRITE;
1944
1945	} else {
1946		if (mask & MAY_EXEC)
1947			av |= DIR__SEARCH;
1948		if (mask & MAY_WRITE)
1949			av |= DIR__WRITE;
1950		if (mask & MAY_READ)
1951			av |= DIR__READ;
1952	}
1953
1954	return av;
1955}
1956
1957/* Convert a Linux file to an access vector. */
1958static inline u32 file_to_av(struct file *file)
1959{
1960	u32 av = 0;
1961
1962	if (file->f_mode & FMODE_READ)
1963		av |= FILE__READ;
1964	if (file->f_mode & FMODE_WRITE) {
1965		if (file->f_flags & O_APPEND)
1966			av |= FILE__APPEND;
1967		else
1968			av |= FILE__WRITE;
1969	}
1970	if (!av) {
1971		/*
1972		 * Special file opened with flags 3 for ioctl-only use.
1973		 */
1974		av = FILE__IOCTL;
1975	}
1976
1977	return av;
1978}
1979
1980/*
1981 * Convert a file to an access vector and include the correct open
1982 * open permission.
1983 */
1984static inline u32 open_file_to_av(struct file *file)
1985{
1986	u32 av = file_to_av(file);
1987	struct inode *inode = file_inode(file);
1988
1989	if (selinux_policycap_openperm() &&
1990	    inode->i_sb->s_magic != SOCKFS_MAGIC)
1991		av |= FILE__OPEN;
1992
1993	return av;
1994}
1995
1996/* Hook functions begin here. */
1997
1998static int selinux_binder_set_context_mgr(struct task_struct *mgr)
1999{
2000	u32 mysid = current_sid();
2001	u32 mgrsid = task_sid(mgr);
2002
2003	return avc_has_perm(&selinux_state,
2004			    mysid, mgrsid, SECCLASS_BINDER,
2005			    BINDER__SET_CONTEXT_MGR, NULL);
2006}
2007
2008static int selinux_binder_transaction(struct task_struct *from,
2009				      struct task_struct *to)
2010{
2011	u32 mysid = current_sid();
2012	u32 fromsid = task_sid(from);
2013	u32 tosid = task_sid(to);
2014	int rc;
2015
2016	if (mysid != fromsid) {
2017		rc = avc_has_perm(&selinux_state,
2018				  mysid, fromsid, SECCLASS_BINDER,
2019				  BINDER__IMPERSONATE, NULL);
2020		if (rc)
2021			return rc;
2022	}
2023
2024	return avc_has_perm(&selinux_state,
2025			    fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2026			    NULL);
2027}
2028
2029static int selinux_binder_transfer_binder(struct task_struct *from,
2030					  struct task_struct *to)
2031{
2032	u32 fromsid = task_sid(from);
2033	u32 tosid = task_sid(to);
2034
2035	return avc_has_perm(&selinux_state,
2036			    fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2037			    NULL);
2038}
2039
2040static int selinux_binder_transfer_file(struct task_struct *from,
2041					struct task_struct *to,
2042					struct file *file)
2043{
2044	u32 sid = task_sid(to);
2045	struct file_security_struct *fsec = selinux_file(file);
2046	struct dentry *dentry = file->f_path.dentry;
2047	struct inode_security_struct *isec;
2048	struct common_audit_data ad;
2049	int rc;
2050
2051	ad.type = LSM_AUDIT_DATA_PATH;
2052	ad.u.path = file->f_path;
2053
2054	if (sid != fsec->sid) {
2055		rc = avc_has_perm(&selinux_state,
2056				  sid, fsec->sid,
2057				  SECCLASS_FD,
2058				  FD__USE,
2059				  &ad);
2060		if (rc)
2061			return rc;
2062	}
2063
2064#ifdef CONFIG_BPF_SYSCALL
2065	rc = bpf_fd_pass(file, sid);
2066	if (rc)
2067		return rc;
2068#endif
2069
2070	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2071		return 0;
2072
2073	isec = backing_inode_security(dentry);
2074	return avc_has_perm(&selinux_state,
2075			    sid, isec->sid, isec->sclass, file_to_av(file),
2076			    &ad);
2077}
2078
2079static int selinux_ptrace_access_check(struct task_struct *child,
2080				     unsigned int mode)
2081{
2082	u32 sid = current_sid();
2083	u32 csid = task_sid(child);
2084
2085	if (mode & PTRACE_MODE_READ)
2086		return avc_has_perm(&selinux_state,
2087				    sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2088
2089	return avc_has_perm(&selinux_state,
2090			    sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2091}
2092
2093static int selinux_ptrace_traceme(struct task_struct *parent)
2094{
2095	return avc_has_perm(&selinux_state,
2096			    task_sid(parent), current_sid(), SECCLASS_PROCESS,
2097			    PROCESS__PTRACE, NULL);
2098}
2099
2100static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2101			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
2102{
2103	return avc_has_perm(&selinux_state,
2104			    current_sid(), task_sid(target), SECCLASS_PROCESS,
2105			    PROCESS__GETCAP, NULL);
2106}
2107
2108static int selinux_capset(struct cred *new, const struct cred *old,
2109			  const kernel_cap_t *effective,
2110			  const kernel_cap_t *inheritable,
2111			  const kernel_cap_t *permitted)
2112{
2113	return avc_has_perm(&selinux_state,
2114			    cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2115			    PROCESS__SETCAP, NULL);
2116}
2117
2118/*
2119 * (This comment used to live with the selinux_task_setuid hook,
2120 * which was removed).
2121 *
2122 * Since setuid only affects the current process, and since the SELinux
2123 * controls are not based on the Linux identity attributes, SELinux does not
2124 * need to control this operation.  However, SELinux does control the use of
2125 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2126 */
2127
2128static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2129			   int cap, unsigned int opts)
2130{
2131	return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2132}
2133
2134static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2135{
2136	const struct cred *cred = current_cred();
2137	int rc = 0;
2138
2139	if (!sb)
2140		return 0;
2141
2142	switch (cmds) {
2143	case Q_SYNC:
2144	case Q_QUOTAON:
2145	case Q_QUOTAOFF:
2146	case Q_SETINFO:
2147	case Q_SETQUOTA:
2148	case Q_XQUOTAOFF:
2149	case Q_XQUOTAON:
2150	case Q_XSETQLIM:
2151		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2152		break;
2153	case Q_GETFMT:
2154	case Q_GETINFO:
2155	case Q_GETQUOTA:
2156	case Q_XGETQUOTA:
2157	case Q_XGETQSTAT:
2158	case Q_XGETQSTATV:
2159	case Q_XGETNEXTQUOTA:
2160		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2161		break;
2162	default:
2163		rc = 0;  /* let the kernel handle invalid cmds */
2164		break;
2165	}
2166	return rc;
2167}
2168
2169static int selinux_quota_on(struct dentry *dentry)
2170{
2171	const struct cred *cred = current_cred();
2172
2173	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2174}
2175
2176static int selinux_syslog(int type)
2177{
2178	switch (type) {
2179	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
2180	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2181		return avc_has_perm(&selinux_state,
2182				    current_sid(), SECINITSID_KERNEL,
2183				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2184	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
2185	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
2186	/* Set level of messages printed to console */
2187	case SYSLOG_ACTION_CONSOLE_LEVEL:
2188		return avc_has_perm(&selinux_state,
2189				    current_sid(), SECINITSID_KERNEL,
2190				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2191				    NULL);
2192	}
2193	/* All other syslog types */
2194	return avc_has_perm(&selinux_state,
2195			    current_sid(), SECINITSID_KERNEL,
2196			    SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2197}
2198
2199/*
2200 * Check that a process has enough memory to allocate a new virtual
2201 * mapping. 0 means there is enough memory for the allocation to
2202 * succeed and -ENOMEM implies there is not.
2203 *
2204 * Do not audit the selinux permission check, as this is applied to all
2205 * processes that allocate mappings.
2206 */
2207static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2208{
2209	int rc, cap_sys_admin = 0;
2210
2211	rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2212				 CAP_OPT_NOAUDIT, true);
2213	if (rc == 0)
2214		cap_sys_admin = 1;
2215
2216	return cap_sys_admin;
2217}
2218
2219/* binprm security operations */
2220
2221static u32 ptrace_parent_sid(void)
2222{
2223	u32 sid = 0;
2224	struct task_struct *tracer;
2225
2226	rcu_read_lock();
2227	tracer = ptrace_parent(current);
2228	if (tracer)
2229		sid = task_sid(tracer);
2230	rcu_read_unlock();
2231
2232	return sid;
2233}
2234
2235static int check_nnp_nosuid(const struct linux_binprm *bprm,
2236			    const struct task_security_struct *old_tsec,
2237			    const struct task_security_struct *new_tsec)
2238{
2239	int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2240	int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2241	int rc;
2242	u32 av;
2243
2244	if (!nnp && !nosuid)
2245		return 0; /* neither NNP nor nosuid */
2246
2247	if (new_tsec->sid == old_tsec->sid)
2248		return 0; /* No change in credentials */
2249
2250	/*
2251	 * If the policy enables the nnp_nosuid_transition policy capability,
2252	 * then we permit transitions under NNP or nosuid if the
2253	 * policy allows the corresponding permission between
2254	 * the old and new contexts.
2255	 */
2256	if (selinux_policycap_nnp_nosuid_transition()) {
2257		av = 0;
2258		if (nnp)
2259			av |= PROCESS2__NNP_TRANSITION;
2260		if (nosuid)
2261			av |= PROCESS2__NOSUID_TRANSITION;
2262		rc = avc_has_perm(&selinux_state,
2263				  old_tsec->sid, new_tsec->sid,
2264				  SECCLASS_PROCESS2, av, NULL);
2265		if (!rc)
2266			return 0;
2267	}
2268
2269	/*
2270	 * We also permit NNP or nosuid transitions to bounded SIDs,
2271	 * i.e. SIDs that are guaranteed to only be allowed a subset
2272	 * of the permissions of the current SID.
2273	 */
2274	rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2275					 new_tsec->sid);
2276	if (!rc)
2277		return 0;
2278
2279	/*
2280	 * On failure, preserve the errno values for NNP vs nosuid.
2281	 * NNP:  Operation not permitted for caller.
2282	 * nosuid:  Permission denied to file.
2283	 */
2284	if (nnp)
2285		return -EPERM;
2286	return -EACCES;
2287}
2288
2289static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2290{
2291	const struct task_security_struct *old_tsec;
2292	struct task_security_struct *new_tsec;
2293	struct inode_security_struct *isec;
2294	struct common_audit_data ad;
2295	struct inode *inode = file_inode(bprm->file);
2296	int rc;
2297
2298	/* SELinux context only depends on initial program or script and not
2299	 * the script interpreter */
2300
2301	old_tsec = selinux_cred(current_cred());
2302	new_tsec = selinux_cred(bprm->cred);
2303	isec = inode_security(inode);
2304
2305	/* Default to the current task SID. */
2306	new_tsec->sid = old_tsec->sid;
2307	new_tsec->osid = old_tsec->sid;
2308
2309	/* Reset fs, key, and sock SIDs on execve. */
2310	new_tsec->create_sid = 0;
2311	new_tsec->keycreate_sid = 0;
2312	new_tsec->sockcreate_sid = 0;
2313
 
 
 
 
 
 
 
 
 
 
 
 
 
2314	if (old_tsec->exec_sid) {
2315		new_tsec->sid = old_tsec->exec_sid;
2316		/* Reset exec SID on execve. */
2317		new_tsec->exec_sid = 0;
2318
2319		/* Fail on NNP or nosuid if not an allowed transition. */
2320		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2321		if (rc)
2322			return rc;
2323	} else {
2324		/* Check for a default transition on this program. */
2325		rc = security_transition_sid(&selinux_state, old_tsec->sid,
2326					     isec->sid, SECCLASS_PROCESS, NULL,
2327					     &new_tsec->sid);
2328		if (rc)
2329			return rc;
2330
2331		/*
2332		 * Fallback to old SID on NNP or nosuid if not an allowed
2333		 * transition.
2334		 */
2335		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2336		if (rc)
2337			new_tsec->sid = old_tsec->sid;
2338	}
2339
2340	ad.type = LSM_AUDIT_DATA_FILE;
2341	ad.u.file = bprm->file;
2342
2343	if (new_tsec->sid == old_tsec->sid) {
2344		rc = avc_has_perm(&selinux_state,
2345				  old_tsec->sid, isec->sid,
2346				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2347		if (rc)
2348			return rc;
2349	} else {
2350		/* Check permissions for the transition. */
2351		rc = avc_has_perm(&selinux_state,
2352				  old_tsec->sid, new_tsec->sid,
2353				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2354		if (rc)
2355			return rc;
2356
2357		rc = avc_has_perm(&selinux_state,
2358				  new_tsec->sid, isec->sid,
2359				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2360		if (rc)
2361			return rc;
2362
2363		/* Check for shared state */
2364		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2365			rc = avc_has_perm(&selinux_state,
2366					  old_tsec->sid, new_tsec->sid,
2367					  SECCLASS_PROCESS, PROCESS__SHARE,
2368					  NULL);
2369			if (rc)
2370				return -EPERM;
2371		}
2372
2373		/* Make sure that anyone attempting to ptrace over a task that
2374		 * changes its SID has the appropriate permit */
2375		if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2376			u32 ptsid = ptrace_parent_sid();
2377			if (ptsid != 0) {
2378				rc = avc_has_perm(&selinux_state,
2379						  ptsid, new_tsec->sid,
2380						  SECCLASS_PROCESS,
2381						  PROCESS__PTRACE, NULL);
2382				if (rc)
2383					return -EPERM;
2384			}
2385		}
2386
2387		/* Clear any possibly unsafe personality bits on exec: */
2388		bprm->per_clear |= PER_CLEAR_ON_SETID;
2389
2390		/* Enable secure mode for SIDs transitions unless
2391		   the noatsecure permission is granted between
2392		   the two SIDs, i.e. ahp returns 0. */
2393		rc = avc_has_perm(&selinux_state,
2394				  old_tsec->sid, new_tsec->sid,
2395				  SECCLASS_PROCESS, PROCESS__NOATSECURE,
2396				  NULL);
2397		bprm->secureexec |= !!rc;
2398	}
2399
2400	return 0;
2401}
2402
2403static int match_file(const void *p, struct file *file, unsigned fd)
2404{
2405	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2406}
2407
2408/* Derived from fs/exec.c:flush_old_files. */
2409static inline void flush_unauthorized_files(const struct cred *cred,
2410					    struct files_struct *files)
2411{
2412	struct file *file, *devnull = NULL;
2413	struct tty_struct *tty;
2414	int drop_tty = 0;
2415	unsigned n;
2416
2417	tty = get_current_tty();
2418	if (tty) {
2419		spin_lock(&tty->files_lock);
2420		if (!list_empty(&tty->tty_files)) {
2421			struct tty_file_private *file_priv;
2422
2423			/* Revalidate access to controlling tty.
2424			   Use file_path_has_perm on the tty path directly
2425			   rather than using file_has_perm, as this particular
2426			   open file may belong to another process and we are
2427			   only interested in the inode-based check here. */
2428			file_priv = list_first_entry(&tty->tty_files,
2429						struct tty_file_private, list);
2430			file = file_priv->file;
2431			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2432				drop_tty = 1;
2433		}
2434		spin_unlock(&tty->files_lock);
2435		tty_kref_put(tty);
2436	}
2437	/* Reset controlling tty. */
2438	if (drop_tty)
2439		no_tty();
2440
2441	/* Revalidate access to inherited open files. */
2442	n = iterate_fd(files, 0, match_file, cred);
2443	if (!n) /* none found? */
2444		return;
2445
2446	devnull = dentry_open(&selinux_null, O_RDWR, cred);
2447	if (IS_ERR(devnull))
2448		devnull = NULL;
2449	/* replace all the matching ones with this */
2450	do {
2451		replace_fd(n - 1, devnull, 0);
2452	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2453	if (devnull)
2454		fput(devnull);
2455}
2456
2457/*
2458 * Prepare a process for imminent new credential changes due to exec
2459 */
2460static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2461{
2462	struct task_security_struct *new_tsec;
2463	struct rlimit *rlim, *initrlim;
2464	int rc, i;
2465
2466	new_tsec = selinux_cred(bprm->cred);
2467	if (new_tsec->sid == new_tsec->osid)
2468		return;
2469
2470	/* Close files for which the new task SID is not authorized. */
2471	flush_unauthorized_files(bprm->cred, current->files);
2472
2473	/* Always clear parent death signal on SID transitions. */
2474	current->pdeath_signal = 0;
2475
2476	/* Check whether the new SID can inherit resource limits from the old
2477	 * SID.  If not, reset all soft limits to the lower of the current
2478	 * task's hard limit and the init task's soft limit.
2479	 *
2480	 * Note that the setting of hard limits (even to lower them) can be
2481	 * controlled by the setrlimit check.  The inclusion of the init task's
2482	 * soft limit into the computation is to avoid resetting soft limits
2483	 * higher than the default soft limit for cases where the default is
2484	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2485	 */
2486	rc = avc_has_perm(&selinux_state,
2487			  new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2488			  PROCESS__RLIMITINH, NULL);
2489	if (rc) {
2490		/* protect against do_prlimit() */
2491		task_lock(current);
2492		for (i = 0; i < RLIM_NLIMITS; i++) {
2493			rlim = current->signal->rlim + i;
2494			initrlim = init_task.signal->rlim + i;
2495			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2496		}
2497		task_unlock(current);
2498		if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2499			update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2500	}
2501}
2502
2503/*
2504 * Clean up the process immediately after the installation of new credentials
2505 * due to exec
2506 */
2507static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2508{
2509	const struct task_security_struct *tsec = selinux_cred(current_cred());
2510	u32 osid, sid;
2511	int rc;
2512
2513	osid = tsec->osid;
2514	sid = tsec->sid;
2515
2516	if (sid == osid)
2517		return;
2518
2519	/* Check whether the new SID can inherit signal state from the old SID.
2520	 * If not, clear itimers to avoid subsequent signal generation and
2521	 * flush and unblock signals.
2522	 *
2523	 * This must occur _after_ the task SID has been updated so that any
2524	 * kill done after the flush will be checked against the new SID.
2525	 */
2526	rc = avc_has_perm(&selinux_state,
2527			  osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2528	if (rc) {
2529		clear_itimer();
2530
2531		spin_lock_irq(&current->sighand->siglock);
2532		if (!fatal_signal_pending(current)) {
2533			flush_sigqueue(&current->pending);
2534			flush_sigqueue(&current->signal->shared_pending);
2535			flush_signal_handlers(current, 1);
2536			sigemptyset(&current->blocked);
2537			recalc_sigpending();
2538		}
2539		spin_unlock_irq(&current->sighand->siglock);
2540	}
2541
2542	/* Wake up the parent if it is waiting so that it can recheck
2543	 * wait permission to the new task SID. */
2544	read_lock(&tasklist_lock);
2545	__wake_up_parent(current, current->real_parent);
2546	read_unlock(&tasklist_lock);
2547}
2548
2549/* superblock security operations */
2550
2551static int selinux_sb_alloc_security(struct super_block *sb)
2552{
2553	struct superblock_security_struct *sbsec;
2554
2555	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
2556	if (!sbsec)
2557		return -ENOMEM;
2558
2559	mutex_init(&sbsec->lock);
2560	INIT_LIST_HEAD(&sbsec->isec_head);
2561	spin_lock_init(&sbsec->isec_lock);
2562	sbsec->sb = sb;
2563	sbsec->sid = SECINITSID_UNLABELED;
2564	sbsec->def_sid = SECINITSID_FILE;
2565	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2566	sb->s_security = sbsec;
2567
2568	return 0;
2569}
2570
2571static void selinux_sb_free_security(struct super_block *sb)
2572{
2573	superblock_free_security(sb);
2574}
2575
2576static inline int opt_len(const char *s)
2577{
2578	bool open_quote = false;
2579	int len;
2580	char c;
2581
2582	for (len = 0; (c = s[len]) != '\0'; len++) {
2583		if (c == '"')
2584			open_quote = !open_quote;
2585		if (c == ',' && !open_quote)
2586			break;
2587	}
2588	return len;
2589}
2590
2591static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2592{
2593	char *from = options;
2594	char *to = options;
2595	bool first = true;
2596	int rc;
2597
2598	while (1) {
2599		int len = opt_len(from);
2600		int token;
2601		char *arg = NULL;
2602
2603		token = match_opt_prefix(from, len, &arg);
2604
2605		if (token != Opt_error) {
2606			char *p, *q;
2607
2608			/* strip quotes */
2609			if (arg) {
2610				for (p = q = arg; p < from + len; p++) {
2611					char c = *p;
2612					if (c != '"')
2613						*q++ = c;
2614				}
2615				arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2616				if (!arg) {
2617					rc = -ENOMEM;
2618					goto free_opt;
2619				}
2620			}
2621			rc = selinux_add_opt(token, arg, mnt_opts);
 
 
2622			if (unlikely(rc)) {
2623				kfree(arg);
2624				goto free_opt;
2625			}
2626		} else {
2627			if (!first) {	// copy with preceding comma
2628				from--;
2629				len++;
2630			}
2631			if (to != from)
2632				memmove(to, from, len);
2633			to += len;
2634			first = false;
2635		}
2636		if (!from[len])
2637			break;
2638		from += len + 1;
2639	}
2640	*to = '\0';
2641	return 0;
2642
2643free_opt:
2644	if (*mnt_opts) {
2645		selinux_free_mnt_opts(*mnt_opts);
2646		*mnt_opts = NULL;
2647	}
2648	return rc;
2649}
2650
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2651static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2652{
2653	struct selinux_mnt_opts *opts = mnt_opts;
2654	struct superblock_security_struct *sbsec = sb->s_security;
2655	u32 sid;
2656	int rc;
2657
2658	if (!(sbsec->flags & SE_SBINITIALIZED))
2659		return 0;
2660
2661	if (!opts)
2662		return 0;
2663
2664	if (opts->fscontext) {
2665		rc = parse_sid(sb, opts->fscontext, &sid);
2666		if (rc)
2667			return rc;
2668		if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2669			goto out_bad_option;
2670	}
2671	if (opts->context) {
2672		rc = parse_sid(sb, opts->context, &sid);
2673		if (rc)
2674			return rc;
2675		if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2676			goto out_bad_option;
2677	}
2678	if (opts->rootcontext) {
2679		struct inode_security_struct *root_isec;
2680		root_isec = backing_inode_security(sb->s_root);
2681		rc = parse_sid(sb, opts->rootcontext, &sid);
2682		if (rc)
2683			return rc;
2684		if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2685			goto out_bad_option;
2686	}
2687	if (opts->defcontext) {
2688		rc = parse_sid(sb, opts->defcontext, &sid);
2689		if (rc)
2690			return rc;
2691		if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2692			goto out_bad_option;
2693	}
2694	return 0;
2695
2696out_bad_option:
2697	pr_warn("SELinux: unable to change security options "
2698	       "during remount (dev %s, type=%s)\n", sb->s_id,
2699	       sb->s_type->name);
2700	return -EINVAL;
2701}
2702
2703static int selinux_sb_kern_mount(struct super_block *sb)
2704{
2705	const struct cred *cred = current_cred();
2706	struct common_audit_data ad;
2707
2708	ad.type = LSM_AUDIT_DATA_DENTRY;
2709	ad.u.dentry = sb->s_root;
2710	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2711}
2712
2713static int selinux_sb_statfs(struct dentry *dentry)
2714{
2715	const struct cred *cred = current_cred();
2716	struct common_audit_data ad;
2717
2718	ad.type = LSM_AUDIT_DATA_DENTRY;
2719	ad.u.dentry = dentry->d_sb->s_root;
2720	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2721}
2722
2723static int selinux_mount(const char *dev_name,
2724			 const struct path *path,
2725			 const char *type,
2726			 unsigned long flags,
2727			 void *data)
2728{
2729	const struct cred *cred = current_cred();
2730
2731	if (flags & MS_REMOUNT)
2732		return superblock_has_perm(cred, path->dentry->d_sb,
2733					   FILESYSTEM__REMOUNT, NULL);
2734	else
2735		return path_has_perm(cred, path, FILE__MOUNTON);
2736}
2737
2738static int selinux_move_mount(const struct path *from_path,
2739			      const struct path *to_path)
2740{
2741	const struct cred *cred = current_cred();
2742
2743	return path_has_perm(cred, to_path, FILE__MOUNTON);
2744}
2745
2746static int selinux_umount(struct vfsmount *mnt, int flags)
2747{
2748	const struct cred *cred = current_cred();
2749
2750	return superblock_has_perm(cred, mnt->mnt_sb,
2751				   FILESYSTEM__UNMOUNT, NULL);
2752}
2753
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2754static int selinux_fs_context_dup(struct fs_context *fc,
2755				  struct fs_context *src_fc)
2756{
2757	const struct selinux_mnt_opts *src = src_fc->security;
2758	struct selinux_mnt_opts *opts;
2759
2760	if (!src)
2761		return 0;
2762
2763	fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
2764	if (!fc->security)
2765		return -ENOMEM;
2766
2767	opts = fc->security;
2768
2769	if (src->fscontext) {
2770		opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL);
2771		if (!opts->fscontext)
2772			return -ENOMEM;
2773	}
2774	if (src->context) {
2775		opts->context = kstrdup(src->context, GFP_KERNEL);
2776		if (!opts->context)
2777			return -ENOMEM;
2778	}
2779	if (src->rootcontext) {
2780		opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL);
2781		if (!opts->rootcontext)
2782			return -ENOMEM;
2783	}
2784	if (src->defcontext) {
2785		opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL);
2786		if (!opts->defcontext)
2787			return -ENOMEM;
2788	}
2789	return 0;
2790}
2791
2792static const struct fs_parameter_spec selinux_fs_parameters[] = {
2793	fsparam_string(CONTEXT_STR,	Opt_context),
2794	fsparam_string(DEFCONTEXT_STR,	Opt_defcontext),
2795	fsparam_string(FSCONTEXT_STR,	Opt_fscontext),
2796	fsparam_string(ROOTCONTEXT_STR,	Opt_rootcontext),
2797	fsparam_flag  (SECLABEL_STR,	Opt_seclabel),
2798	{}
2799};
2800
2801static int selinux_fs_context_parse_param(struct fs_context *fc,
2802					  struct fs_parameter *param)
2803{
2804	struct fs_parse_result result;
2805	int opt, rc;
2806
2807	opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2808	if (opt < 0)
2809		return opt;
2810
2811	rc = selinux_add_opt(opt, param->string, &fc->security);
2812	if (!rc) {
2813		param->string = NULL;
2814		rc = 1;
2815	}
2816	return rc;
2817}
2818
2819/* inode security operations */
2820
2821static int selinux_inode_alloc_security(struct inode *inode)
2822{
2823	struct inode_security_struct *isec = selinux_inode(inode);
2824	u32 sid = current_sid();
2825
2826	spin_lock_init(&isec->lock);
2827	INIT_LIST_HEAD(&isec->list);
2828	isec->inode = inode;
2829	isec->sid = SECINITSID_UNLABELED;
2830	isec->sclass = SECCLASS_FILE;
2831	isec->task_sid = sid;
2832	isec->initialized = LABEL_INVALID;
2833
2834	return 0;
2835}
2836
2837static void selinux_inode_free_security(struct inode *inode)
2838{
2839	inode_free_security(inode);
2840}
2841
2842static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2843					const struct qstr *name, void **ctx,
 
2844					u32 *ctxlen)
2845{
2846	u32 newsid;
2847	int rc;
2848
2849	rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2850					   d_inode(dentry->d_parent), name,
2851					   inode_mode_to_security_class(mode),
2852					   &newsid);
2853	if (rc)
2854		return rc;
2855
2856	return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
 
 
 
2857				       ctxlen);
2858}
2859
2860static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2861					  struct qstr *name,
2862					  const struct cred *old,
2863					  struct cred *new)
2864{
2865	u32 newsid;
2866	int rc;
2867	struct task_security_struct *tsec;
2868
2869	rc = selinux_determine_inode_label(selinux_cred(old),
2870					   d_inode(dentry->d_parent), name,
2871					   inode_mode_to_security_class(mode),
2872					   &newsid);
2873	if (rc)
2874		return rc;
2875
2876	tsec = selinux_cred(new);
2877	tsec->create_sid = newsid;
2878	return 0;
2879}
2880
2881static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2882				       const struct qstr *qstr,
2883				       const char **name,
2884				       void **value, size_t *len)
2885{
2886	const struct task_security_struct *tsec = selinux_cred(current_cred());
2887	struct superblock_security_struct *sbsec;
 
2888	u32 newsid, clen;
2889	int rc;
2890	char *context;
2891
2892	sbsec = dir->i_sb->s_security;
2893
2894	newsid = tsec->create_sid;
2895
2896	rc = selinux_determine_inode_label(tsec, dir, qstr,
2897		inode_mode_to_security_class(inode->i_mode),
2898		&newsid);
2899	if (rc)
2900		return rc;
2901
2902	/* Possibly defer initialization to selinux_complete_init. */
2903	if (sbsec->flags & SE_SBINITIALIZED) {
2904		struct inode_security_struct *isec = selinux_inode(inode);
2905		isec->sclass = inode_mode_to_security_class(inode->i_mode);
2906		isec->sid = newsid;
2907		isec->initialized = LABEL_INITIALIZED;
2908	}
2909
2910	if (!selinux_initialized(&selinux_state) ||
2911	    !(sbsec->flags & SBLABEL_MNT))
2912		return -EOPNOTSUPP;
2913
2914	if (name)
2915		*name = XATTR_SELINUX_SUFFIX;
2916
2917	if (value && len) {
2918		rc = security_sid_to_context_force(&selinux_state, newsid,
2919						   &context, &clen);
2920		if (rc)
2921			return rc;
2922		*value = context;
2923		*len = clen;
 
2924	}
2925
2926	return 0;
2927}
2928
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2929static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2930{
2931	return may_create(dir, dentry, SECCLASS_FILE);
2932}
2933
2934static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2935{
2936	return may_link(dir, old_dentry, MAY_LINK);
2937}
2938
2939static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2940{
2941	return may_link(dir, dentry, MAY_UNLINK);
2942}
2943
2944static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2945{
2946	return may_create(dir, dentry, SECCLASS_LNK_FILE);
2947}
2948
2949static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2950{
2951	return may_create(dir, dentry, SECCLASS_DIR);
2952}
2953
2954static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2955{
2956	return may_link(dir, dentry, MAY_RMDIR);
2957}
2958
2959static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2960{
2961	return may_create(dir, dentry, inode_mode_to_security_class(mode));
2962}
2963
2964static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2965				struct inode *new_inode, struct dentry *new_dentry)
2966{
2967	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2968}
2969
2970static int selinux_inode_readlink(struct dentry *dentry)
2971{
2972	const struct cred *cred = current_cred();
2973
2974	return dentry_has_perm(cred, dentry, FILE__READ);
2975}
2976
2977static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2978				     bool rcu)
2979{
2980	const struct cred *cred = current_cred();
2981	struct common_audit_data ad;
2982	struct inode_security_struct *isec;
2983	u32 sid;
2984
2985	validate_creds(cred);
2986
2987	ad.type = LSM_AUDIT_DATA_DENTRY;
2988	ad.u.dentry = dentry;
2989	sid = cred_sid(cred);
2990	isec = inode_security_rcu(inode, rcu);
2991	if (IS_ERR(isec))
2992		return PTR_ERR(isec);
2993
2994	return avc_has_perm_flags(&selinux_state,
2995				  sid, isec->sid, isec->sclass, FILE__READ, &ad,
2996				  rcu ? MAY_NOT_BLOCK : 0);
2997}
2998
2999static noinline int audit_inode_permission(struct inode *inode,
3000					   u32 perms, u32 audited, u32 denied,
3001					   int result)
3002{
3003	struct common_audit_data ad;
3004	struct inode_security_struct *isec = selinux_inode(inode);
3005	int rc;
3006
3007	ad.type = LSM_AUDIT_DATA_INODE;
3008	ad.u.inode = inode;
3009
3010	rc = slow_avc_audit(&selinux_state,
3011			    current_sid(), isec->sid, isec->sclass, perms,
3012			    audited, denied, result, &ad);
3013	if (rc)
3014		return rc;
3015	return 0;
3016}
3017
3018static int selinux_inode_permission(struct inode *inode, int mask)
3019{
3020	const struct cred *cred = current_cred();
3021	u32 perms;
3022	bool from_access;
3023	bool no_block = mask & MAY_NOT_BLOCK;
3024	struct inode_security_struct *isec;
3025	u32 sid;
3026	struct av_decision avd;
3027	int rc, rc2;
3028	u32 audited, denied;
3029
3030	from_access = mask & MAY_ACCESS;
3031	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3032
3033	/* No permission to check.  Existence test. */
3034	if (!mask)
3035		return 0;
3036
3037	validate_creds(cred);
3038
3039	if (unlikely(IS_PRIVATE(inode)))
3040		return 0;
3041
3042	perms = file_mask_to_av(inode->i_mode, mask);
3043
3044	sid = cred_sid(cred);
3045	isec = inode_security_rcu(inode, no_block);
3046	if (IS_ERR(isec))
3047		return PTR_ERR(isec);
3048
3049	rc = avc_has_perm_noaudit(&selinux_state,
3050				  sid, isec->sid, isec->sclass, perms,
3051				  no_block ? AVC_NONBLOCKING : 0,
3052				  &avd);
3053	audited = avc_audit_required(perms, &avd, rc,
3054				     from_access ? FILE__AUDIT_ACCESS : 0,
3055				     &denied);
3056	if (likely(!audited))
3057		return rc;
3058
3059	/* fall back to ref-walk if we have to generate audit */
3060	if (no_block)
3061		return -ECHILD;
3062
3063	rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3064	if (rc2)
3065		return rc2;
3066	return rc;
3067}
3068
3069static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3070{
3071	const struct cred *cred = current_cred();
3072	struct inode *inode = d_backing_inode(dentry);
3073	unsigned int ia_valid = iattr->ia_valid;
3074	__u32 av = FILE__WRITE;
3075
3076	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3077	if (ia_valid & ATTR_FORCE) {
3078		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3079			      ATTR_FORCE);
3080		if (!ia_valid)
3081			return 0;
3082	}
3083
3084	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3085			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3086		return dentry_has_perm(cred, dentry, FILE__SETATTR);
3087
3088	if (selinux_policycap_openperm() &&
3089	    inode->i_sb->s_magic != SOCKFS_MAGIC &&
3090	    (ia_valid & ATTR_SIZE) &&
3091	    !(ia_valid & ATTR_FILE))
3092		av |= FILE__OPEN;
3093
3094	return dentry_has_perm(cred, dentry, av);
3095}
3096
3097static int selinux_inode_getattr(const struct path *path)
3098{
3099	return path_has_perm(current_cred(), path, FILE__GETATTR);
3100}
3101
3102static bool has_cap_mac_admin(bool audit)
3103{
3104	const struct cred *cred = current_cred();
3105	unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3106
3107	if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3108		return false;
3109	if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3110		return false;
3111	return true;
3112}
3113
3114static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
 
3115				  const void *value, size_t size, int flags)
3116{
3117	struct inode *inode = d_backing_inode(dentry);
3118	struct inode_security_struct *isec;
3119	struct superblock_security_struct *sbsec;
3120	struct common_audit_data ad;
3121	u32 newsid, sid = current_sid();
3122	int rc = 0;
3123
3124	if (strcmp(name, XATTR_NAME_SELINUX)) {
3125		rc = cap_inode_setxattr(dentry, name, value, size, flags);
3126		if (rc)
3127			return rc;
3128
3129		/* Not an attribute we recognize, so just check the
3130		   ordinary setattr permission. */
3131		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3132	}
3133
3134	if (!selinux_initialized(&selinux_state))
3135		return (inode_owner_or_capable(inode) ? 0 : -EPERM);
3136
3137	sbsec = inode->i_sb->s_security;
3138	if (!(sbsec->flags & SBLABEL_MNT))
3139		return -EOPNOTSUPP;
3140
3141	if (!inode_owner_or_capable(inode))
3142		return -EPERM;
3143
3144	ad.type = LSM_AUDIT_DATA_DENTRY;
3145	ad.u.dentry = dentry;
3146
3147	isec = backing_inode_security(dentry);
3148	rc = avc_has_perm(&selinux_state,
3149			  sid, isec->sid, isec->sclass,
3150			  FILE__RELABELFROM, &ad);
3151	if (rc)
3152		return rc;
3153
3154	rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3155				     GFP_KERNEL);
3156	if (rc == -EINVAL) {
3157		if (!has_cap_mac_admin(true)) {
3158			struct audit_buffer *ab;
3159			size_t audit_size;
3160
3161			/* We strip a nul only if it is at the end, otherwise the
3162			 * context contains a nul and we should audit that */
3163			if (value) {
3164				const char *str = value;
3165
3166				if (str[size - 1] == '\0')
3167					audit_size = size - 1;
3168				else
3169					audit_size = size;
3170			} else {
3171				audit_size = 0;
3172			}
3173			ab = audit_log_start(audit_context(),
3174					     GFP_ATOMIC, AUDIT_SELINUX_ERR);
 
 
3175			audit_log_format(ab, "op=setxattr invalid_context=");
3176			audit_log_n_untrustedstring(ab, value, audit_size);
3177			audit_log_end(ab);
3178
3179			return rc;
3180		}
3181		rc = security_context_to_sid_force(&selinux_state, value,
3182						   size, &newsid);
3183	}
3184	if (rc)
3185		return rc;
3186
3187	rc = avc_has_perm(&selinux_state,
3188			  sid, newsid, isec->sclass,
3189			  FILE__RELABELTO, &ad);
3190	if (rc)
3191		return rc;
3192
3193	rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3194					  sid, isec->sclass);
3195	if (rc)
3196		return rc;
3197
3198	return avc_has_perm(&selinux_state,
3199			    newsid,
3200			    sbsec->sid,
3201			    SECCLASS_FILESYSTEM,
3202			    FILESYSTEM__ASSOCIATE,
3203			    &ad);
3204}
3205
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3206static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3207					const void *value, size_t size,
3208					int flags)
3209{
3210	struct inode *inode = d_backing_inode(dentry);
3211	struct inode_security_struct *isec;
3212	u32 newsid;
3213	int rc;
3214
3215	if (strcmp(name, XATTR_NAME_SELINUX)) {
3216		/* Not an attribute we recognize, so nothing to do. */
3217		return;
3218	}
3219
3220	if (!selinux_initialized(&selinux_state)) {
3221		/* If we haven't even been initialized, then we can't validate
3222		 * against a policy, so leave the label as invalid. It may
3223		 * resolve to a valid label on the next revalidation try if
3224		 * we've since initialized.
3225		 */
3226		return;
3227	}
3228
3229	rc = security_context_to_sid_force(&selinux_state, value, size,
3230					   &newsid);
3231	if (rc) {
3232		pr_err("SELinux:  unable to map context to SID"
3233		       "for (%s, %lu), rc=%d\n",
3234		       inode->i_sb->s_id, inode->i_ino, -rc);
3235		return;
3236	}
3237
3238	isec = backing_inode_security(dentry);
3239	spin_lock(&isec->lock);
3240	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3241	isec->sid = newsid;
3242	isec->initialized = LABEL_INITIALIZED;
3243	spin_unlock(&isec->lock);
3244
3245	return;
3246}
3247
3248static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3249{
3250	const struct cred *cred = current_cred();
3251
3252	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3253}
3254
3255static int selinux_inode_listxattr(struct dentry *dentry)
3256{
3257	const struct cred *cred = current_cred();
3258
3259	return dentry_has_perm(cred, dentry, FILE__GETATTR);
3260}
3261
3262static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
 
3263{
3264	if (strcmp(name, XATTR_NAME_SELINUX)) {
3265		int rc = cap_inode_removexattr(dentry, name);
3266		if (rc)
3267			return rc;
3268
3269		/* Not an attribute we recognize, so just check the
3270		   ordinary setattr permission. */
3271		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3272	}
3273
 
 
 
3274	/* No one is allowed to remove a SELinux security label.
3275	   You can change the label, but all data must be labeled. */
3276	return -EACCES;
3277}
3278
3279static int selinux_path_notify(const struct path *path, u64 mask,
3280						unsigned int obj_type)
3281{
3282	int ret;
3283	u32 perm;
3284
3285	struct common_audit_data ad;
3286
3287	ad.type = LSM_AUDIT_DATA_PATH;
3288	ad.u.path = *path;
3289
3290	/*
3291	 * Set permission needed based on the type of mark being set.
3292	 * Performs an additional check for sb watches.
3293	 */
3294	switch (obj_type) {
3295	case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3296		perm = FILE__WATCH_MOUNT;
3297		break;
3298	case FSNOTIFY_OBJ_TYPE_SB:
3299		perm = FILE__WATCH_SB;
3300		ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3301						FILESYSTEM__WATCH, &ad);
3302		if (ret)
3303			return ret;
3304		break;
3305	case FSNOTIFY_OBJ_TYPE_INODE:
3306		perm = FILE__WATCH;
3307		break;
3308	default:
3309		return -EINVAL;
3310	}
3311
3312	/* blocking watches require the file:watch_with_perm permission */
3313	if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3314		perm |= FILE__WATCH_WITH_PERM;
3315
3316	/* watches on read-like events need the file:watch_reads permission */
3317	if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3318		perm |= FILE__WATCH_READS;
3319
3320	return path_has_perm(current_cred(), path, perm);
3321}
3322
3323/*
3324 * Copy the inode security context value to the user.
3325 *
3326 * Permission check is handled by selinux_inode_getxattr hook.
3327 */
3328static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
 
 
3329{
3330	u32 size;
3331	int error;
3332	char *context = NULL;
3333	struct inode_security_struct *isec;
3334
3335	/*
3336	 * If we're not initialized yet, then we can't validate contexts, so
3337	 * just let vfs_getxattr fall back to using the on-disk xattr.
3338	 */
3339	if (!selinux_initialized(&selinux_state) ||
3340	    strcmp(name, XATTR_SELINUX_SUFFIX))
3341		return -EOPNOTSUPP;
3342
3343	/*
3344	 * If the caller has CAP_MAC_ADMIN, then get the raw context
3345	 * value even if it is not defined by current policy; otherwise,
3346	 * use the in-core value under current policy.
3347	 * Use the non-auditing forms of the permission checks since
3348	 * getxattr may be called by unprivileged processes commonly
3349	 * and lack of permission just means that we fall back to the
3350	 * in-core context value, not a denial.
3351	 */
3352	isec = inode_security(inode);
3353	if (has_cap_mac_admin(false))
3354		error = security_sid_to_context_force(&selinux_state,
3355						      isec->sid, &context,
3356						      &size);
3357	else
3358		error = security_sid_to_context(&selinux_state, isec->sid,
3359						&context, &size);
3360	if (error)
3361		return error;
3362	error = size;
3363	if (alloc) {
3364		*buffer = context;
3365		goto out_nofree;
3366	}
3367	kfree(context);
3368out_nofree:
3369	return error;
3370}
3371
3372static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3373				     const void *value, size_t size, int flags)
3374{
3375	struct inode_security_struct *isec = inode_security_novalidate(inode);
3376	struct superblock_security_struct *sbsec = inode->i_sb->s_security;
3377	u32 newsid;
3378	int rc;
3379
3380	if (strcmp(name, XATTR_SELINUX_SUFFIX))
3381		return -EOPNOTSUPP;
3382
 
3383	if (!(sbsec->flags & SBLABEL_MNT))
3384		return -EOPNOTSUPP;
3385
3386	if (!value || !size)
3387		return -EACCES;
3388
3389	rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3390				     GFP_KERNEL);
3391	if (rc)
3392		return rc;
3393
3394	spin_lock(&isec->lock);
3395	isec->sclass = inode_mode_to_security_class(inode->i_mode);
3396	isec->sid = newsid;
3397	isec->initialized = LABEL_INITIALIZED;
3398	spin_unlock(&isec->lock);
3399	return 0;
3400}
3401
3402static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3403{
3404	const int len = sizeof(XATTR_NAME_SELINUX);
 
 
 
 
3405	if (buffer && len <= buffer_size)
3406		memcpy(buffer, XATTR_NAME_SELINUX, len);
3407	return len;
3408}
3409
3410static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3411{
3412	struct inode_security_struct *isec = inode_security_novalidate(inode);
3413	*secid = isec->sid;
3414}
3415
3416static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3417{
3418	u32 sid;
3419	struct task_security_struct *tsec;
3420	struct cred *new_creds = *new;
3421
3422	if (new_creds == NULL) {
3423		new_creds = prepare_creds();
3424		if (!new_creds)
3425			return -ENOMEM;
3426	}
3427
3428	tsec = selinux_cred(new_creds);
3429	/* Get label from overlay inode and set it in create_sid */
3430	selinux_inode_getsecid(d_inode(src), &sid);
3431	tsec->create_sid = sid;
3432	*new = new_creds;
3433	return 0;
3434}
3435
3436static int selinux_inode_copy_up_xattr(const char *name)
3437{
3438	/* The copy_up hook above sets the initial context on an inode, but we
3439	 * don't then want to overwrite it by blindly copying all the lower
3440	 * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3441	 */
3442	if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3443		return 1; /* Discard */
3444	/*
3445	 * Any other attribute apart from SELINUX is not claimed, supported
3446	 * by selinux.
3447	 */
3448	return -EOPNOTSUPP;
3449}
3450
3451/* kernfs node operations */
3452
3453static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3454					struct kernfs_node *kn)
3455{
3456	const struct task_security_struct *tsec = selinux_cred(current_cred());
3457	u32 parent_sid, newsid, clen;
3458	int rc;
3459	char *context;
3460
3461	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3462	if (rc == -ENODATA)
3463		return 0;
3464	else if (rc < 0)
3465		return rc;
3466
3467	clen = (u32)rc;
3468	context = kmalloc(clen, GFP_KERNEL);
3469	if (!context)
3470		return -ENOMEM;
3471
3472	rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3473	if (rc < 0) {
3474		kfree(context);
3475		return rc;
3476	}
3477
3478	rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
3479				     GFP_KERNEL);
3480	kfree(context);
3481	if (rc)
3482		return rc;
3483
3484	if (tsec->create_sid) {
3485		newsid = tsec->create_sid;
3486	} else {
3487		u16 secclass = inode_mode_to_security_class(kn->mode);
3488		struct qstr q;
3489
3490		q.name = kn->name;
3491		q.hash_len = hashlen_string(kn_dir, kn->name);
3492
3493		rc = security_transition_sid(&selinux_state, tsec->sid,
3494					     parent_sid, secclass, &q,
3495					     &newsid);
3496		if (rc)
3497			return rc;
3498	}
3499
3500	rc = security_sid_to_context_force(&selinux_state, newsid,
3501					   &context, &clen);
3502	if (rc)
3503		return rc;
3504
3505	rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3506			      XATTR_CREATE);
3507	kfree(context);
3508	return rc;
3509}
3510
3511
3512/* file security operations */
3513
3514static int selinux_revalidate_file_permission(struct file *file, int mask)
3515{
3516	const struct cred *cred = current_cred();
3517	struct inode *inode = file_inode(file);
3518
3519	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3520	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3521		mask |= MAY_APPEND;
3522
3523	return file_has_perm(cred, file,
3524			     file_mask_to_av(inode->i_mode, mask));
3525}
3526
3527static int selinux_file_permission(struct file *file, int mask)
3528{
3529	struct inode *inode = file_inode(file);
3530	struct file_security_struct *fsec = selinux_file(file);
3531	struct inode_security_struct *isec;
3532	u32 sid = current_sid();
3533
3534	if (!mask)
3535		/* No permission to check.  Existence test. */
3536		return 0;
3537
3538	isec = inode_security(inode);
3539	if (sid == fsec->sid && fsec->isid == isec->sid &&
3540	    fsec->pseqno == avc_policy_seqno(&selinux_state))
3541		/* No change since file_open check. */
3542		return 0;
3543
3544	return selinux_revalidate_file_permission(file, mask);
3545}
3546
3547static int selinux_file_alloc_security(struct file *file)
3548{
3549	struct file_security_struct *fsec = selinux_file(file);
3550	u32 sid = current_sid();
3551
3552	fsec->sid = sid;
3553	fsec->fown_sid = sid;
3554
3555	return 0;
3556}
3557
3558/*
3559 * Check whether a task has the ioctl permission and cmd
3560 * operation to an inode.
3561 */
3562static int ioctl_has_perm(const struct cred *cred, struct file *file,
3563		u32 requested, u16 cmd)
3564{
3565	struct common_audit_data ad;
3566	struct file_security_struct *fsec = selinux_file(file);
3567	struct inode *inode = file_inode(file);
3568	struct inode_security_struct *isec;
3569	struct lsm_ioctlop_audit ioctl;
3570	u32 ssid = cred_sid(cred);
3571	int rc;
3572	u8 driver = cmd >> 8;
3573	u8 xperm = cmd & 0xff;
3574
3575	ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3576	ad.u.op = &ioctl;
3577	ad.u.op->cmd = cmd;
3578	ad.u.op->path = file->f_path;
3579
3580	if (ssid != fsec->sid) {
3581		rc = avc_has_perm(&selinux_state,
3582				  ssid, fsec->sid,
3583				SECCLASS_FD,
3584				FD__USE,
3585				&ad);
3586		if (rc)
3587			goto out;
3588	}
3589
3590	if (unlikely(IS_PRIVATE(inode)))
3591		return 0;
3592
3593	isec = inode_security(inode);
3594	rc = avc_has_extended_perms(&selinux_state,
3595				    ssid, isec->sid, isec->sclass,
3596				    requested, driver, xperm, &ad);
3597out:
3598	return rc;
3599}
3600
3601static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3602			      unsigned long arg)
3603{
3604	const struct cred *cred = current_cred();
3605	int error = 0;
3606
3607	switch (cmd) {
3608	case FIONREAD:
3609	case FIBMAP:
3610	case FIGETBSZ:
3611	case FS_IOC_GETFLAGS:
3612	case FS_IOC_GETVERSION:
3613		error = file_has_perm(cred, file, FILE__GETATTR);
3614		break;
3615
3616	case FS_IOC_SETFLAGS:
3617	case FS_IOC_SETVERSION:
3618		error = file_has_perm(cred, file, FILE__SETATTR);
3619		break;
3620
3621	/* sys_ioctl() checks */
3622	case FIONBIO:
3623	case FIOASYNC:
3624		error = file_has_perm(cred, file, 0);
3625		break;
3626
3627	case KDSKBENT:
3628	case KDSKBSENT:
3629		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3630					    CAP_OPT_NONE, true);
3631		break;
3632
 
 
 
 
 
 
3633	/* default case assumes that the command will go
3634	 * to the file's ioctl() function.
3635	 */
3636	default:
3637		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3638	}
3639	return error;
3640}
3641
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3642static int default_noexec __ro_after_init;
3643
3644static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3645{
3646	const struct cred *cred = current_cred();
3647	u32 sid = cred_sid(cred);
3648	int rc = 0;
3649
3650	if (default_noexec &&
3651	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3652				   (!shared && (prot & PROT_WRITE)))) {
3653		/*
3654		 * We are making executable an anonymous mapping or a
3655		 * private file mapping that will also be writable.
3656		 * This has an additional check.
3657		 */
3658		rc = avc_has_perm(&selinux_state,
3659				  sid, sid, SECCLASS_PROCESS,
3660				  PROCESS__EXECMEM, NULL);
3661		if (rc)
3662			goto error;
3663	}
3664
3665	if (file) {
3666		/* read access is always possible with a mapping */
3667		u32 av = FILE__READ;
3668
3669		/* write access only matters if the mapping is shared */
3670		if (shared && (prot & PROT_WRITE))
3671			av |= FILE__WRITE;
3672
3673		if (prot & PROT_EXEC)
3674			av |= FILE__EXECUTE;
3675
3676		return file_has_perm(cred, file, av);
3677	}
3678
3679error:
3680	return rc;
3681}
3682
3683static int selinux_mmap_addr(unsigned long addr)
3684{
3685	int rc = 0;
3686
3687	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3688		u32 sid = current_sid();
3689		rc = avc_has_perm(&selinux_state,
3690				  sid, sid, SECCLASS_MEMPROTECT,
3691				  MEMPROTECT__MMAP_ZERO, NULL);
3692	}
3693
3694	return rc;
3695}
3696
3697static int selinux_mmap_file(struct file *file, unsigned long reqprot,
 
3698			     unsigned long prot, unsigned long flags)
3699{
3700	struct common_audit_data ad;
3701	int rc;
3702
3703	if (file) {
3704		ad.type = LSM_AUDIT_DATA_FILE;
3705		ad.u.file = file;
3706		rc = inode_has_perm(current_cred(), file_inode(file),
3707				    FILE__MAP, &ad);
3708		if (rc)
3709			return rc;
3710	}
3711
3712	if (selinux_state.checkreqprot)
3713		prot = reqprot;
3714
3715	return file_map_prot_check(file, prot,
3716				   (flags & MAP_TYPE) == MAP_SHARED);
3717}
3718
3719static int selinux_file_mprotect(struct vm_area_struct *vma,
3720				 unsigned long reqprot,
3721				 unsigned long prot)
3722{
3723	const struct cred *cred = current_cred();
3724	u32 sid = cred_sid(cred);
3725
3726	if (selinux_state.checkreqprot)
3727		prot = reqprot;
3728
3729	if (default_noexec &&
3730	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3731		int rc = 0;
3732		if (vma->vm_start >= vma->vm_mm->start_brk &&
3733		    vma->vm_end <= vma->vm_mm->brk) {
3734			rc = avc_has_perm(&selinux_state,
3735					  sid, sid, SECCLASS_PROCESS,
3736					  PROCESS__EXECHEAP, NULL);
3737		} else if (!vma->vm_file &&
3738			   ((vma->vm_start <= vma->vm_mm->start_stack &&
3739			     vma->vm_end >= vma->vm_mm->start_stack) ||
3740			    vma_is_stack_for_current(vma))) {
3741			rc = avc_has_perm(&selinux_state,
3742					  sid, sid, SECCLASS_PROCESS,
3743					  PROCESS__EXECSTACK, NULL);
3744		} else if (vma->vm_file && vma->anon_vma) {
3745			/*
3746			 * We are making executable a file mapping that has
3747			 * had some COW done. Since pages might have been
3748			 * written, check ability to execute the possibly
3749			 * modified content.  This typically should only
3750			 * occur for text relocations.
3751			 */
3752			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3753		}
3754		if (rc)
3755			return rc;
3756	}
3757
3758	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3759}
3760
3761static int selinux_file_lock(struct file *file, unsigned int cmd)
3762{
3763	const struct cred *cred = current_cred();
3764
3765	return file_has_perm(cred, file, FILE__LOCK);
3766}
3767
3768static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3769			      unsigned long arg)
3770{
3771	const struct cred *cred = current_cred();
3772	int err = 0;
3773
3774	switch (cmd) {
3775	case F_SETFL:
3776		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3777			err = file_has_perm(cred, file, FILE__WRITE);
3778			break;
3779		}
3780		fallthrough;
3781	case F_SETOWN:
3782	case F_SETSIG:
3783	case F_GETFL:
3784	case F_GETOWN:
3785	case F_GETSIG:
3786	case F_GETOWNER_UIDS:
3787		/* Just check FD__USE permission */
3788		err = file_has_perm(cred, file, 0);
3789		break;
3790	case F_GETLK:
3791	case F_SETLK:
3792	case F_SETLKW:
3793	case F_OFD_GETLK:
3794	case F_OFD_SETLK:
3795	case F_OFD_SETLKW:
3796#if BITS_PER_LONG == 32
3797	case F_GETLK64:
3798	case F_SETLK64:
3799	case F_SETLKW64:
3800#endif
3801		err = file_has_perm(cred, file, FILE__LOCK);
3802		break;
3803	}
3804
3805	return err;
3806}
3807
3808static void selinux_file_set_fowner(struct file *file)
3809{
3810	struct file_security_struct *fsec;
3811
3812	fsec = selinux_file(file);
3813	fsec->fown_sid = current_sid();
3814}
3815
3816static int selinux_file_send_sigiotask(struct task_struct *tsk,
3817				       struct fown_struct *fown, int signum)
3818{
3819	struct file *file;
3820	u32 sid = task_sid(tsk);
3821	u32 perm;
3822	struct file_security_struct *fsec;
3823
3824	/* struct fown_struct is never outside the context of a struct file */
3825	file = container_of(fown, struct file, f_owner);
3826
3827	fsec = selinux_file(file);
3828
3829	if (!signum)
3830		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3831	else
3832		perm = signal_to_av(signum);
3833
3834	return avc_has_perm(&selinux_state,
3835			    fsec->fown_sid, sid,
3836			    SECCLASS_PROCESS, perm, NULL);
3837}
3838
3839static int selinux_file_receive(struct file *file)
3840{
3841	const struct cred *cred = current_cred();
3842
3843	return file_has_perm(cred, file, file_to_av(file));
3844}
3845
3846static int selinux_file_open(struct file *file)
3847{
3848	struct file_security_struct *fsec;
3849	struct inode_security_struct *isec;
3850
3851	fsec = selinux_file(file);
3852	isec = inode_security(file_inode(file));
3853	/*
3854	 * Save inode label and policy sequence number
3855	 * at open-time so that selinux_file_permission
3856	 * can determine whether revalidation is necessary.
3857	 * Task label is already saved in the file security
3858	 * struct as its SID.
3859	 */
3860	fsec->isid = isec->sid;
3861	fsec->pseqno = avc_policy_seqno(&selinux_state);
3862	/*
3863	 * Since the inode label or policy seqno may have changed
3864	 * between the selinux_inode_permission check and the saving
3865	 * of state above, recheck that access is still permitted.
3866	 * Otherwise, access might never be revalidated against the
3867	 * new inode label or new policy.
3868	 * This check is not redundant - do not remove.
3869	 */
3870	return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3871}
3872
3873/* task security operations */
3874
3875static int selinux_task_alloc(struct task_struct *task,
3876			      unsigned long clone_flags)
3877{
3878	u32 sid = current_sid();
3879
3880	return avc_has_perm(&selinux_state,
3881			    sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3882}
3883
3884/*
3885 * prepare a new set of credentials for modification
3886 */
3887static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3888				gfp_t gfp)
3889{
3890	const struct task_security_struct *old_tsec = selinux_cred(old);
3891	struct task_security_struct *tsec = selinux_cred(new);
3892
3893	*tsec = *old_tsec;
3894	return 0;
3895}
3896
3897/*
3898 * transfer the SELinux data to a blank set of creds
3899 */
3900static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3901{
3902	const struct task_security_struct *old_tsec = selinux_cred(old);
3903	struct task_security_struct *tsec = selinux_cred(new);
3904
3905	*tsec = *old_tsec;
3906}
3907
3908static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3909{
3910	*secid = cred_sid(c);
3911}
3912
3913/*
3914 * set the security data for a kernel service
3915 * - all the creation contexts are set to unlabelled
3916 */
3917static int selinux_kernel_act_as(struct cred *new, u32 secid)
3918{
3919	struct task_security_struct *tsec = selinux_cred(new);
3920	u32 sid = current_sid();
3921	int ret;
3922
3923	ret = avc_has_perm(&selinux_state,
3924			   sid, secid,
3925			   SECCLASS_KERNEL_SERVICE,
3926			   KERNEL_SERVICE__USE_AS_OVERRIDE,
3927			   NULL);
3928	if (ret == 0) {
3929		tsec->sid = secid;
3930		tsec->create_sid = 0;
3931		tsec->keycreate_sid = 0;
3932		tsec->sockcreate_sid = 0;
3933	}
3934	return ret;
3935}
3936
3937/*
3938 * set the file creation context in a security record to the same as the
3939 * objective context of the specified inode
3940 */
3941static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3942{
3943	struct inode_security_struct *isec = inode_security(inode);
3944	struct task_security_struct *tsec = selinux_cred(new);
3945	u32 sid = current_sid();
3946	int ret;
3947
3948	ret = avc_has_perm(&selinux_state,
3949			   sid, isec->sid,
3950			   SECCLASS_KERNEL_SERVICE,
3951			   KERNEL_SERVICE__CREATE_FILES_AS,
3952			   NULL);
3953
3954	if (ret == 0)
3955		tsec->create_sid = isec->sid;
3956	return ret;
3957}
3958
3959static int selinux_kernel_module_request(char *kmod_name)
3960{
3961	struct common_audit_data ad;
3962
3963	ad.type = LSM_AUDIT_DATA_KMOD;
3964	ad.u.kmod_name = kmod_name;
3965
3966	return avc_has_perm(&selinux_state,
3967			    current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3968			    SYSTEM__MODULE_REQUEST, &ad);
3969}
3970
3971static int selinux_kernel_module_from_file(struct file *file)
3972{
3973	struct common_audit_data ad;
3974	struct inode_security_struct *isec;
3975	struct file_security_struct *fsec;
3976	u32 sid = current_sid();
3977	int rc;
3978
3979	/* init_module */
3980	if (file == NULL)
3981		return avc_has_perm(&selinux_state,
3982				    sid, sid, SECCLASS_SYSTEM,
3983					SYSTEM__MODULE_LOAD, NULL);
3984
3985	/* finit_module */
3986
3987	ad.type = LSM_AUDIT_DATA_FILE;
3988	ad.u.file = file;
3989
3990	fsec = selinux_file(file);
3991	if (sid != fsec->sid) {
3992		rc = avc_has_perm(&selinux_state,
3993				  sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3994		if (rc)
3995			return rc;
3996	}
3997
3998	isec = inode_security(file_inode(file));
3999	return avc_has_perm(&selinux_state,
4000			    sid, isec->sid, SECCLASS_SYSTEM,
4001				SYSTEM__MODULE_LOAD, &ad);
4002}
4003
4004static int selinux_kernel_read_file(struct file *file,
4005				    enum kernel_read_file_id id)
 
4006{
4007	int rc = 0;
4008
4009	switch (id) {
4010	case READING_MODULE:
4011		rc = selinux_kernel_module_from_file(file);
4012		break;
4013	default:
4014		break;
4015	}
4016
4017	return rc;
4018}
4019
4020static int selinux_kernel_load_data(enum kernel_load_data_id id)
4021{
4022	int rc = 0;
4023
4024	switch (id) {
4025	case LOADING_MODULE:
4026		rc = selinux_kernel_module_from_file(NULL);
 
4027	default:
4028		break;
4029	}
4030
4031	return rc;
4032}
4033
4034static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4035{
4036	return avc_has_perm(&selinux_state,
4037			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4038			    PROCESS__SETPGID, NULL);
4039}
4040
4041static int selinux_task_getpgid(struct task_struct *p)
4042{
4043	return avc_has_perm(&selinux_state,
4044			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4045			    PROCESS__GETPGID, NULL);
4046}
4047
4048static int selinux_task_getsid(struct task_struct *p)
4049{
4050	return avc_has_perm(&selinux_state,
4051			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4052			    PROCESS__GETSESSION, NULL);
4053}
4054
4055static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4056{
4057	*secid = task_sid(p);
 
 
 
 
 
4058}
4059
4060static int selinux_task_setnice(struct task_struct *p, int nice)
4061{
4062	return avc_has_perm(&selinux_state,
4063			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4064			    PROCESS__SETSCHED, NULL);
4065}
4066
4067static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4068{
4069	return avc_has_perm(&selinux_state,
4070			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4071			    PROCESS__SETSCHED, NULL);
4072}
4073
4074static int selinux_task_getioprio(struct task_struct *p)
4075{
4076	return avc_has_perm(&selinux_state,
4077			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4078			    PROCESS__GETSCHED, NULL);
4079}
4080
4081static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4082				unsigned int flags)
4083{
4084	u32 av = 0;
4085
4086	if (!flags)
4087		return 0;
4088	if (flags & LSM_PRLIMIT_WRITE)
4089		av |= PROCESS__SETRLIMIT;
4090	if (flags & LSM_PRLIMIT_READ)
4091		av |= PROCESS__GETRLIMIT;
4092	return avc_has_perm(&selinux_state,
4093			    cred_sid(cred), cred_sid(tcred),
4094			    SECCLASS_PROCESS, av, NULL);
4095}
4096
4097static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4098		struct rlimit *new_rlim)
4099{
4100	struct rlimit *old_rlim = p->signal->rlim + resource;
4101
4102	/* Control the ability to change the hard limit (whether
4103	   lowering or raising it), so that the hard limit can
4104	   later be used as a safe reset point for the soft limit
4105	   upon context transitions.  See selinux_bprm_committing_creds. */
4106	if (old_rlim->rlim_max != new_rlim->rlim_max)
4107		return avc_has_perm(&selinux_state,
4108				    current_sid(), task_sid(p),
4109				    SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4110
4111	return 0;
4112}
4113
4114static int selinux_task_setscheduler(struct task_struct *p)
4115{
4116	return avc_has_perm(&selinux_state,
4117			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4118			    PROCESS__SETSCHED, NULL);
4119}
4120
4121static int selinux_task_getscheduler(struct task_struct *p)
4122{
4123	return avc_has_perm(&selinux_state,
4124			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4125			    PROCESS__GETSCHED, NULL);
4126}
4127
4128static int selinux_task_movememory(struct task_struct *p)
4129{
4130	return avc_has_perm(&selinux_state,
4131			    current_sid(), task_sid(p), SECCLASS_PROCESS,
4132			    PROCESS__SETSCHED, NULL);
4133}
4134
4135static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4136				int sig, const struct cred *cred)
4137{
4138	u32 secid;
4139	u32 perm;
4140
4141	if (!sig)
4142		perm = PROCESS__SIGNULL; /* null signal; existence test */
4143	else
4144		perm = signal_to_av(sig);
4145	if (!cred)
4146		secid = current_sid();
4147	else
4148		secid = cred_sid(cred);
4149	return avc_has_perm(&selinux_state,
4150			    secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4151}
4152
4153static void selinux_task_to_inode(struct task_struct *p,
4154				  struct inode *inode)
4155{
4156	struct inode_security_struct *isec = selinux_inode(inode);
4157	u32 sid = task_sid(p);
4158
4159	spin_lock(&isec->lock);
4160	isec->sclass = inode_mode_to_security_class(inode->i_mode);
4161	isec->sid = sid;
4162	isec->initialized = LABEL_INITIALIZED;
4163	spin_unlock(&isec->lock);
4164}
4165
 
 
 
 
 
 
 
 
4166/* Returns error only if unable to parse addresses */
4167static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4168			struct common_audit_data *ad, u8 *proto)
4169{
4170	int offset, ihlen, ret = -EINVAL;
4171	struct iphdr _iph, *ih;
4172
4173	offset = skb_network_offset(skb);
4174	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4175	if (ih == NULL)
4176		goto out;
4177
4178	ihlen = ih->ihl * 4;
4179	if (ihlen < sizeof(_iph))
4180		goto out;
4181
4182	ad->u.net->v4info.saddr = ih->saddr;
4183	ad->u.net->v4info.daddr = ih->daddr;
4184	ret = 0;
4185
4186	if (proto)
4187		*proto = ih->protocol;
4188
4189	switch (ih->protocol) {
4190	case IPPROTO_TCP: {
4191		struct tcphdr _tcph, *th;
4192
4193		if (ntohs(ih->frag_off) & IP_OFFSET)
4194			break;
4195
4196		offset += ihlen;
4197		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4198		if (th == NULL)
4199			break;
4200
4201		ad->u.net->sport = th->source;
4202		ad->u.net->dport = th->dest;
4203		break;
4204	}
4205
4206	case IPPROTO_UDP: {
4207		struct udphdr _udph, *uh;
4208
4209		if (ntohs(ih->frag_off) & IP_OFFSET)
4210			break;
4211
4212		offset += ihlen;
4213		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4214		if (uh == NULL)
4215			break;
4216
4217		ad->u.net->sport = uh->source;
4218		ad->u.net->dport = uh->dest;
4219		break;
4220	}
4221
4222	case IPPROTO_DCCP: {
4223		struct dccp_hdr _dccph, *dh;
4224
4225		if (ntohs(ih->frag_off) & IP_OFFSET)
4226			break;
4227
4228		offset += ihlen;
4229		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4230		if (dh == NULL)
4231			break;
4232
4233		ad->u.net->sport = dh->dccph_sport;
4234		ad->u.net->dport = dh->dccph_dport;
4235		break;
4236	}
4237
4238#if IS_ENABLED(CONFIG_IP_SCTP)
4239	case IPPROTO_SCTP: {
4240		struct sctphdr _sctph, *sh;
4241
4242		if (ntohs(ih->frag_off) & IP_OFFSET)
4243			break;
4244
4245		offset += ihlen;
4246		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4247		if (sh == NULL)
4248			break;
4249
4250		ad->u.net->sport = sh->source;
4251		ad->u.net->dport = sh->dest;
4252		break;
4253	}
4254#endif
4255	default:
4256		break;
4257	}
4258out:
4259	return ret;
4260}
4261
4262#if IS_ENABLED(CONFIG_IPV6)
4263
4264/* Returns error only if unable to parse addresses */
4265static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4266			struct common_audit_data *ad, u8 *proto)
4267{
4268	u8 nexthdr;
4269	int ret = -EINVAL, offset;
4270	struct ipv6hdr _ipv6h, *ip6;
4271	__be16 frag_off;
4272
4273	offset = skb_network_offset(skb);
4274	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4275	if (ip6 == NULL)
4276		goto out;
4277
4278	ad->u.net->v6info.saddr = ip6->saddr;
4279	ad->u.net->v6info.daddr = ip6->daddr;
4280	ret = 0;
4281
4282	nexthdr = ip6->nexthdr;
4283	offset += sizeof(_ipv6h);
4284	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4285	if (offset < 0)
4286		goto out;
4287
4288	if (proto)
4289		*proto = nexthdr;
4290
4291	switch (nexthdr) {
4292	case IPPROTO_TCP: {
4293		struct tcphdr _tcph, *th;
4294
4295		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4296		if (th == NULL)
4297			break;
4298
4299		ad->u.net->sport = th->source;
4300		ad->u.net->dport = th->dest;
4301		break;
4302	}
4303
4304	case IPPROTO_UDP: {
4305		struct udphdr _udph, *uh;
4306
4307		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4308		if (uh == NULL)
4309			break;
4310
4311		ad->u.net->sport = uh->source;
4312		ad->u.net->dport = uh->dest;
4313		break;
4314	}
4315
4316	case IPPROTO_DCCP: {
4317		struct dccp_hdr _dccph, *dh;
4318
4319		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4320		if (dh == NULL)
4321			break;
4322
4323		ad->u.net->sport = dh->dccph_sport;
4324		ad->u.net->dport = dh->dccph_dport;
4325		break;
4326	}
4327
4328#if IS_ENABLED(CONFIG_IP_SCTP)
4329	case IPPROTO_SCTP: {
4330		struct sctphdr _sctph, *sh;
4331
4332		sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4333		if (sh == NULL)
4334			break;
4335
4336		ad->u.net->sport = sh->source;
4337		ad->u.net->dport = sh->dest;
4338		break;
4339	}
4340#endif
4341	/* includes fragments */
4342	default:
4343		break;
4344	}
4345out:
4346	return ret;
4347}
4348
4349#endif /* IPV6 */
4350
4351static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4352			     char **_addrp, int src, u8 *proto)
4353{
4354	char *addrp;
4355	int ret;
4356
4357	switch (ad->u.net->family) {
4358	case PF_INET:
4359		ret = selinux_parse_skb_ipv4(skb, ad, proto);
4360		if (ret)
4361			goto parse_error;
4362		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4363				       &ad->u.net->v4info.daddr);
4364		goto okay;
4365
4366#if IS_ENABLED(CONFIG_IPV6)
4367	case PF_INET6:
4368		ret = selinux_parse_skb_ipv6(skb, ad, proto);
4369		if (ret)
4370			goto parse_error;
4371		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4372				       &ad->u.net->v6info.daddr);
4373		goto okay;
4374#endif	/* IPV6 */
4375	default:
4376		addrp = NULL;
4377		goto okay;
4378	}
4379
4380parse_error:
4381	pr_warn(
4382	       "SELinux: failure in selinux_parse_skb(),"
4383	       " unable to parse packet\n");
4384	return ret;
4385
4386okay:
4387	if (_addrp)
4388		*_addrp = addrp;
4389	return 0;
4390}
4391
4392/**
4393 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4394 * @skb: the packet
4395 * @family: protocol family
4396 * @sid: the packet's peer label SID
4397 *
4398 * Description:
4399 * Check the various different forms of network peer labeling and determine
4400 * the peer label/SID for the packet; most of the magic actually occurs in
4401 * the security server function security_net_peersid_cmp().  The function
4402 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4403 * or -EACCES if @sid is invalid due to inconsistencies with the different
4404 * peer labels.
4405 *
4406 */
4407static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4408{
4409	int err;
4410	u32 xfrm_sid;
4411	u32 nlbl_sid;
4412	u32 nlbl_type;
4413
4414	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4415	if (unlikely(err))
4416		return -EACCES;
4417	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4418	if (unlikely(err))
4419		return -EACCES;
4420
4421	err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4422					   nlbl_type, xfrm_sid, sid);
4423	if (unlikely(err)) {
4424		pr_warn(
4425		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
4426		       " unable to determine packet's peer label\n");
4427		return -EACCES;
4428	}
4429
4430	return 0;
4431}
4432
4433/**
4434 * selinux_conn_sid - Determine the child socket label for a connection
4435 * @sk_sid: the parent socket's SID
4436 * @skb_sid: the packet's SID
4437 * @conn_sid: the resulting connection SID
4438 *
4439 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4440 * combined with the MLS information from @skb_sid in order to create
4441 * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
4442 * of @sk_sid.  Returns zero on success, negative values on failure.
4443 *
4444 */
4445static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4446{
4447	int err = 0;
4448
4449	if (skb_sid != SECSID_NULL)
4450		err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4451					    conn_sid);
4452	else
4453		*conn_sid = sk_sid;
4454
4455	return err;
4456}
4457
4458/* socket security operations */
4459
4460static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4461				 u16 secclass, u32 *socksid)
4462{
4463	if (tsec->sockcreate_sid > SECSID_NULL) {
4464		*socksid = tsec->sockcreate_sid;
4465		return 0;
4466	}
4467
4468	return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4469				       secclass, NULL, socksid);
4470}
4471
4472static int sock_has_perm(struct sock *sk, u32 perms)
4473{
4474	struct sk_security_struct *sksec = sk->sk_security;
4475	struct common_audit_data ad;
4476	struct lsm_network_audit net = {0,};
4477
4478	if (sksec->sid == SECINITSID_KERNEL)
4479		return 0;
4480
4481	ad.type = LSM_AUDIT_DATA_NET;
4482	ad.u.net = &net;
4483	ad.u.net->sk = sk;
 
 
 
 
 
 
 
 
 
 
 
 
 
4484
4485	return avc_has_perm(&selinux_state,
4486			    current_sid(), sksec->sid, sksec->sclass, perms,
4487			    &ad);
4488}
4489
4490static int selinux_socket_create(int family, int type,
4491				 int protocol, int kern)
4492{
4493	const struct task_security_struct *tsec = selinux_cred(current_cred());
4494	u32 newsid;
4495	u16 secclass;
4496	int rc;
4497
4498	if (kern)
4499		return 0;
4500
4501	secclass = socket_type_to_security_class(family, type, protocol);
4502	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4503	if (rc)
4504		return rc;
4505
4506	return avc_has_perm(&selinux_state,
4507			    tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4508}
4509
4510static int selinux_socket_post_create(struct socket *sock, int family,
4511				      int type, int protocol, int kern)
4512{
4513	const struct task_security_struct *tsec = selinux_cred(current_cred());
4514	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4515	struct sk_security_struct *sksec;
4516	u16 sclass = socket_type_to_security_class(family, type, protocol);
4517	u32 sid = SECINITSID_KERNEL;
4518	int err = 0;
4519
4520	if (!kern) {
4521		err = socket_sockcreate_sid(tsec, sclass, &sid);
4522		if (err)
4523			return err;
4524	}
4525
4526	isec->sclass = sclass;
4527	isec->sid = sid;
4528	isec->initialized = LABEL_INITIALIZED;
4529
4530	if (sock->sk) {
4531		sksec = sock->sk->sk_security;
4532		sksec->sclass = sclass;
4533		sksec->sid = sid;
4534		/* Allows detection of the first association on this socket */
4535		if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4536			sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4537
4538		err = selinux_netlbl_socket_post_create(sock->sk, family);
4539	}
4540
4541	return err;
4542}
4543
4544static int selinux_socket_socketpair(struct socket *socka,
4545				     struct socket *sockb)
4546{
4547	struct sk_security_struct *sksec_a = socka->sk->sk_security;
4548	struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4549
4550	sksec_a->peer_sid = sksec_b->sid;
4551	sksec_b->peer_sid = sksec_a->sid;
4552
4553	return 0;
4554}
4555
4556/* Range of port numbers used to automatically bind.
4557   Need to determine whether we should perform a name_bind
4558   permission check between the socket and the port number. */
4559
4560static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4561{
4562	struct sock *sk = sock->sk;
4563	struct sk_security_struct *sksec = sk->sk_security;
4564	u16 family;
4565	int err;
4566
4567	err = sock_has_perm(sk, SOCKET__BIND);
4568	if (err)
4569		goto out;
4570
4571	/* If PF_INET or PF_INET6, check name_bind permission for the port. */
4572	family = sk->sk_family;
4573	if (family == PF_INET || family == PF_INET6) {
4574		char *addrp;
4575		struct common_audit_data ad;
4576		struct lsm_network_audit net = {0,};
4577		struct sockaddr_in *addr4 = NULL;
4578		struct sockaddr_in6 *addr6 = NULL;
4579		u16 family_sa;
4580		unsigned short snum;
4581		u32 sid, node_perm;
4582
4583		/*
4584		 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4585		 * that validates multiple binding addresses. Because of this
4586		 * need to check address->sa_family as it is possible to have
4587		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4588		 */
4589		if (addrlen < offsetofend(struct sockaddr, sa_family))
4590			return -EINVAL;
4591		family_sa = address->sa_family;
4592		switch (family_sa) {
4593		case AF_UNSPEC:
4594		case AF_INET:
4595			if (addrlen < sizeof(struct sockaddr_in))
4596				return -EINVAL;
4597			addr4 = (struct sockaddr_in *)address;
4598			if (family_sa == AF_UNSPEC) {
 
 
 
 
 
 
 
4599				/* see __inet_bind(), we only want to allow
4600				 * AF_UNSPEC if the address is INADDR_ANY
4601				 */
4602				if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4603					goto err_af;
4604				family_sa = AF_INET;
4605			}
4606			snum = ntohs(addr4->sin_port);
4607			addrp = (char *)&addr4->sin_addr.s_addr;
4608			break;
4609		case AF_INET6:
4610			if (addrlen < SIN6_LEN_RFC2133)
4611				return -EINVAL;
4612			addr6 = (struct sockaddr_in6 *)address;
4613			snum = ntohs(addr6->sin6_port);
4614			addrp = (char *)&addr6->sin6_addr.s6_addr;
4615			break;
4616		default:
4617			goto err_af;
4618		}
4619
4620		ad.type = LSM_AUDIT_DATA_NET;
4621		ad.u.net = &net;
4622		ad.u.net->sport = htons(snum);
4623		ad.u.net->family = family_sa;
4624
4625		if (snum) {
4626			int low, high;
4627
4628			inet_get_local_port_range(sock_net(sk), &low, &high);
4629
4630			if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4631			    snum < low || snum > high) {
4632				err = sel_netport_sid(sk->sk_protocol,
4633						      snum, &sid);
4634				if (err)
4635					goto out;
4636				err = avc_has_perm(&selinux_state,
4637						   sksec->sid, sid,
4638						   sksec->sclass,
4639						   SOCKET__NAME_BIND, &ad);
4640				if (err)
4641					goto out;
4642			}
4643		}
4644
4645		switch (sksec->sclass) {
4646		case SECCLASS_TCP_SOCKET:
4647			node_perm = TCP_SOCKET__NODE_BIND;
4648			break;
4649
4650		case SECCLASS_UDP_SOCKET:
4651			node_perm = UDP_SOCKET__NODE_BIND;
4652			break;
4653
4654		case SECCLASS_DCCP_SOCKET:
4655			node_perm = DCCP_SOCKET__NODE_BIND;
4656			break;
4657
4658		case SECCLASS_SCTP_SOCKET:
4659			node_perm = SCTP_SOCKET__NODE_BIND;
4660			break;
4661
4662		default:
4663			node_perm = RAWIP_SOCKET__NODE_BIND;
4664			break;
4665		}
4666
4667		err = sel_netnode_sid(addrp, family_sa, &sid);
4668		if (err)
4669			goto out;
4670
4671		if (family_sa == AF_INET)
4672			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4673		else
4674			ad.u.net->v6info.saddr = addr6->sin6_addr;
4675
4676		err = avc_has_perm(&selinux_state,
4677				   sksec->sid, sid,
4678				   sksec->sclass, node_perm, &ad);
4679		if (err)
4680			goto out;
4681	}
4682out:
4683	return err;
4684err_af:
4685	/* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4686	if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4687		return -EINVAL;
4688	return -EAFNOSUPPORT;
4689}
4690
4691/* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4692 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4693 */
4694static int selinux_socket_connect_helper(struct socket *sock,
4695					 struct sockaddr *address, int addrlen)
4696{
4697	struct sock *sk = sock->sk;
4698	struct sk_security_struct *sksec = sk->sk_security;
4699	int err;
4700
4701	err = sock_has_perm(sk, SOCKET__CONNECT);
4702	if (err)
4703		return err;
4704	if (addrlen < offsetofend(struct sockaddr, sa_family))
4705		return -EINVAL;
4706
4707	/* connect(AF_UNSPEC) has special handling, as it is a documented
4708	 * way to disconnect the socket
4709	 */
4710	if (address->sa_family == AF_UNSPEC)
4711		return 0;
4712
4713	/*
4714	 * If a TCP, DCCP or SCTP socket, check name_connect permission
4715	 * for the port.
4716	 */
4717	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4718	    sksec->sclass == SECCLASS_DCCP_SOCKET ||
4719	    sksec->sclass == SECCLASS_SCTP_SOCKET) {
4720		struct common_audit_data ad;
4721		struct lsm_network_audit net = {0,};
4722		struct sockaddr_in *addr4 = NULL;
4723		struct sockaddr_in6 *addr6 = NULL;
4724		unsigned short snum;
4725		u32 sid, perm;
4726
4727		/* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4728		 * that validates multiple connect addresses. Because of this
4729		 * need to check address->sa_family as it is possible to have
4730		 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4731		 */
4732		switch (address->sa_family) {
4733		case AF_INET:
4734			addr4 = (struct sockaddr_in *)address;
4735			if (addrlen < sizeof(struct sockaddr_in))
4736				return -EINVAL;
4737			snum = ntohs(addr4->sin_port);
4738			break;
4739		case AF_INET6:
4740			addr6 = (struct sockaddr_in6 *)address;
4741			if (addrlen < SIN6_LEN_RFC2133)
4742				return -EINVAL;
4743			snum = ntohs(addr6->sin6_port);
4744			break;
4745		default:
4746			/* Note that SCTP services expect -EINVAL, whereas
4747			 * others expect -EAFNOSUPPORT.
4748			 */
4749			if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4750				return -EINVAL;
4751			else
4752				return -EAFNOSUPPORT;
4753		}
4754
4755		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4756		if (err)
4757			return err;
4758
4759		switch (sksec->sclass) {
4760		case SECCLASS_TCP_SOCKET:
4761			perm = TCP_SOCKET__NAME_CONNECT;
4762			break;
4763		case SECCLASS_DCCP_SOCKET:
4764			perm = DCCP_SOCKET__NAME_CONNECT;
4765			break;
4766		case SECCLASS_SCTP_SOCKET:
4767			perm = SCTP_SOCKET__NAME_CONNECT;
4768			break;
4769		}
4770
4771		ad.type = LSM_AUDIT_DATA_NET;
4772		ad.u.net = &net;
4773		ad.u.net->dport = htons(snum);
4774		ad.u.net->family = address->sa_family;
4775		err = avc_has_perm(&selinux_state,
4776				   sksec->sid, sid, sksec->sclass, perm, &ad);
4777		if (err)
4778			return err;
4779	}
4780
4781	return 0;
4782}
4783
4784/* Supports connect(2), see comments in selinux_socket_connect_helper() */
4785static int selinux_socket_connect(struct socket *sock,
4786				  struct sockaddr *address, int addrlen)
4787{
4788	int err;
4789	struct sock *sk = sock->sk;
4790
4791	err = selinux_socket_connect_helper(sock, address, addrlen);
4792	if (err)
4793		return err;
4794
4795	return selinux_netlbl_socket_connect(sk, address);
4796}
4797
4798static int selinux_socket_listen(struct socket *sock, int backlog)
4799{
4800	return sock_has_perm(sock->sk, SOCKET__LISTEN);
4801}
4802
4803static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4804{
4805	int err;
4806	struct inode_security_struct *isec;
4807	struct inode_security_struct *newisec;
4808	u16 sclass;
4809	u32 sid;
4810
4811	err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4812	if (err)
4813		return err;
4814
4815	isec = inode_security_novalidate(SOCK_INODE(sock));
4816	spin_lock(&isec->lock);
4817	sclass = isec->sclass;
4818	sid = isec->sid;
4819	spin_unlock(&isec->lock);
4820
4821	newisec = inode_security_novalidate(SOCK_INODE(newsock));
4822	newisec->sclass = sclass;
4823	newisec->sid = sid;
4824	newisec->initialized = LABEL_INITIALIZED;
4825
4826	return 0;
4827}
4828
4829static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4830				  int size)
4831{
4832	return sock_has_perm(sock->sk, SOCKET__WRITE);
4833}
4834
4835static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4836				  int size, int flags)
4837{
4838	return sock_has_perm(sock->sk, SOCKET__READ);
4839}
4840
4841static int selinux_socket_getsockname(struct socket *sock)
4842{
4843	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4844}
4845
4846static int selinux_socket_getpeername(struct socket *sock)
4847{
4848	return sock_has_perm(sock->sk, SOCKET__GETATTR);
4849}
4850
4851static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4852{
4853	int err;
4854
4855	err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4856	if (err)
4857		return err;
4858
4859	return selinux_netlbl_socket_setsockopt(sock, level, optname);
4860}
4861
4862static int selinux_socket_getsockopt(struct socket *sock, int level,
4863				     int optname)
4864{
4865	return sock_has_perm(sock->sk, SOCKET__GETOPT);
4866}
4867
4868static int selinux_socket_shutdown(struct socket *sock, int how)
4869{
4870	return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4871}
4872
4873static int selinux_socket_unix_stream_connect(struct sock *sock,
4874					      struct sock *other,
4875					      struct sock *newsk)
4876{
4877	struct sk_security_struct *sksec_sock = sock->sk_security;
4878	struct sk_security_struct *sksec_other = other->sk_security;
4879	struct sk_security_struct *sksec_new = newsk->sk_security;
4880	struct common_audit_data ad;
4881	struct lsm_network_audit net = {0,};
4882	int err;
4883
4884	ad.type = LSM_AUDIT_DATA_NET;
4885	ad.u.net = &net;
4886	ad.u.net->sk = other;
4887
4888	err = avc_has_perm(&selinux_state,
4889			   sksec_sock->sid, sksec_other->sid,
4890			   sksec_other->sclass,
4891			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4892	if (err)
4893		return err;
4894
4895	/* server child socket */
4896	sksec_new->peer_sid = sksec_sock->sid;
4897	err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4898				    sksec_sock->sid, &sksec_new->sid);
4899	if (err)
4900		return err;
4901
4902	/* connecting socket */
4903	sksec_sock->peer_sid = sksec_new->sid;
4904
4905	return 0;
4906}
4907
4908static int selinux_socket_unix_may_send(struct socket *sock,
4909					struct socket *other)
4910{
4911	struct sk_security_struct *ssec = sock->sk->sk_security;
4912	struct sk_security_struct *osec = other->sk->sk_security;
4913	struct common_audit_data ad;
4914	struct lsm_network_audit net = {0,};
4915
4916	ad.type = LSM_AUDIT_DATA_NET;
4917	ad.u.net = &net;
4918	ad.u.net->sk = other->sk;
4919
4920	return avc_has_perm(&selinux_state,
4921			    ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4922			    &ad);
4923}
4924
4925static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4926				    char *addrp, u16 family, u32 peer_sid,
4927				    struct common_audit_data *ad)
4928{
4929	int err;
4930	u32 if_sid;
4931	u32 node_sid;
4932
4933	err = sel_netif_sid(ns, ifindex, &if_sid);
4934	if (err)
4935		return err;
4936	err = avc_has_perm(&selinux_state,
4937			   peer_sid, if_sid,
4938			   SECCLASS_NETIF, NETIF__INGRESS, ad);
4939	if (err)
4940		return err;
4941
4942	err = sel_netnode_sid(addrp, family, &node_sid);
4943	if (err)
4944		return err;
4945	return avc_has_perm(&selinux_state,
4946			    peer_sid, node_sid,
4947			    SECCLASS_NODE, NODE__RECVFROM, ad);
4948}
4949
4950static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4951				       u16 family)
4952{
4953	int err = 0;
4954	struct sk_security_struct *sksec = sk->sk_security;
4955	u32 sk_sid = sksec->sid;
4956	struct common_audit_data ad;
4957	struct lsm_network_audit net = {0,};
4958	char *addrp;
4959
4960	ad.type = LSM_AUDIT_DATA_NET;
4961	ad.u.net = &net;
4962	ad.u.net->netif = skb->skb_iif;
4963	ad.u.net->family = family;
4964	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4965	if (err)
4966		return err;
4967
4968	if (selinux_secmark_enabled()) {
4969		err = avc_has_perm(&selinux_state,
4970				   sk_sid, skb->secmark, SECCLASS_PACKET,
4971				   PACKET__RECV, &ad);
4972		if (err)
4973			return err;
4974	}
4975
4976	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4977	if (err)
4978		return err;
4979	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4980
4981	return err;
4982}
4983
4984static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4985{
4986	int err;
4987	struct sk_security_struct *sksec = sk->sk_security;
4988	u16 family = sk->sk_family;
4989	u32 sk_sid = sksec->sid;
4990	struct common_audit_data ad;
4991	struct lsm_network_audit net = {0,};
4992	char *addrp;
4993	u8 secmark_active;
4994	u8 peerlbl_active;
4995
4996	if (family != PF_INET && family != PF_INET6)
4997		return 0;
4998
4999	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
5000	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5001		family = PF_INET;
5002
5003	/* If any sort of compatibility mode is enabled then handoff processing
5004	 * to the selinux_sock_rcv_skb_compat() function to deal with the
5005	 * special handling.  We do this in an attempt to keep this function
5006	 * as fast and as clean as possible. */
5007	if (!selinux_policycap_netpeer())
5008		return selinux_sock_rcv_skb_compat(sk, skb, family);
5009
5010	secmark_active = selinux_secmark_enabled();
5011	peerlbl_active = selinux_peerlbl_enabled();
5012	if (!secmark_active && !peerlbl_active)
5013		return 0;
5014
5015	ad.type = LSM_AUDIT_DATA_NET;
5016	ad.u.net = &net;
5017	ad.u.net->netif = skb->skb_iif;
5018	ad.u.net->family = family;
5019	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5020	if (err)
5021		return err;
5022
5023	if (peerlbl_active) {
5024		u32 peer_sid;
5025
5026		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5027		if (err)
5028			return err;
5029		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5030					       addrp, family, peer_sid, &ad);
5031		if (err) {
5032			selinux_netlbl_err(skb, family, err, 0);
5033			return err;
5034		}
5035		err = avc_has_perm(&selinux_state,
5036				   sk_sid, peer_sid, SECCLASS_PEER,
5037				   PEER__RECV, &ad);
5038		if (err) {
5039			selinux_netlbl_err(skb, family, err, 0);
5040			return err;
5041		}
5042	}
5043
5044	if (secmark_active) {
5045		err = avc_has_perm(&selinux_state,
5046				   sk_sid, skb->secmark, SECCLASS_PACKET,
5047				   PACKET__RECV, &ad);
5048		if (err)
5049			return err;
5050	}
5051
5052	return err;
5053}
5054
5055static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5056					    int __user *optlen, unsigned len)
 
5057{
5058	int err = 0;
5059	char *scontext;
5060	u32 scontext_len;
5061	struct sk_security_struct *sksec = sock->sk->sk_security;
5062	u32 peer_sid = SECSID_NULL;
5063
5064	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5065	    sksec->sclass == SECCLASS_TCP_SOCKET ||
5066	    sksec->sclass == SECCLASS_SCTP_SOCKET)
5067		peer_sid = sksec->peer_sid;
5068	if (peer_sid == SECSID_NULL)
5069		return -ENOPROTOOPT;
5070
5071	err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5072				      &scontext_len);
5073	if (err)
5074		return err;
5075
5076	if (scontext_len > len) {
5077		err = -ERANGE;
5078		goto out_len;
5079	}
5080
5081	if (copy_to_user(optval, scontext, scontext_len))
5082		err = -EFAULT;
5083
5084out_len:
5085	if (put_user(scontext_len, optlen))
5086		err = -EFAULT;
5087	kfree(scontext);
5088	return err;
5089}
5090
5091static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5092{
5093	u32 peer_secid = SECSID_NULL;
5094	u16 family;
5095	struct inode_security_struct *isec;
5096
5097	if (skb && skb->protocol == htons(ETH_P_IP))
5098		family = PF_INET;
5099	else if (skb && skb->protocol == htons(ETH_P_IPV6))
5100		family = PF_INET6;
5101	else if (sock)
5102		family = sock->sk->sk_family;
5103	else
5104		goto out;
5105
5106	if (sock && family == PF_UNIX) {
5107		isec = inode_security_novalidate(SOCK_INODE(sock));
5108		peer_secid = isec->sid;
5109	} else if (skb)
5110		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5111
5112out:
5113	*secid = peer_secid;
5114	if (peer_secid == SECSID_NULL)
5115		return -EINVAL;
5116	return 0;
5117}
5118
5119static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5120{
5121	struct sk_security_struct *sksec;
5122
5123	sksec = kzalloc(sizeof(*sksec), priority);
5124	if (!sksec)
5125		return -ENOMEM;
5126
5127	sksec->peer_sid = SECINITSID_UNLABELED;
5128	sksec->sid = SECINITSID_UNLABELED;
5129	sksec->sclass = SECCLASS_SOCKET;
5130	selinux_netlbl_sk_security_reset(sksec);
5131	sk->sk_security = sksec;
5132
5133	return 0;
5134}
5135
5136static void selinux_sk_free_security(struct sock *sk)
5137{
5138	struct sk_security_struct *sksec = sk->sk_security;
5139
5140	sk->sk_security = NULL;
5141	selinux_netlbl_sk_security_free(sksec);
5142	kfree(sksec);
5143}
5144
5145static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5146{
5147	struct sk_security_struct *sksec = sk->sk_security;
5148	struct sk_security_struct *newsksec = newsk->sk_security;
5149
5150	newsksec->sid = sksec->sid;
5151	newsksec->peer_sid = sksec->peer_sid;
5152	newsksec->sclass = sksec->sclass;
5153
5154	selinux_netlbl_sk_security_reset(newsksec);
5155}
5156
5157static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5158{
5159	if (!sk)
5160		*secid = SECINITSID_ANY_SOCKET;
5161	else {
5162		struct sk_security_struct *sksec = sk->sk_security;
5163
5164		*secid = sksec->sid;
5165	}
5166}
5167
5168static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5169{
5170	struct inode_security_struct *isec =
5171		inode_security_novalidate(SOCK_INODE(parent));
5172	struct sk_security_struct *sksec = sk->sk_security;
5173
5174	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5175	    sk->sk_family == PF_UNIX)
5176		isec->sid = sksec->sid;
5177	sksec->sclass = isec->sclass;
5178}
5179
5180/* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5181 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5182 * already present).
5183 */
5184static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5185				      struct sk_buff *skb)
5186{
5187	struct sk_security_struct *sksec = ep->base.sk->sk_security;
 
 
5188	struct common_audit_data ad;
5189	struct lsm_network_audit net = {0,};
5190	u8 peerlbl_active;
5191	u32 peer_sid = SECINITSID_UNLABELED;
5192	u32 conn_sid;
5193	int err = 0;
5194
5195	if (!selinux_policycap_extsockclass())
5196		return 0;
 
5197
5198	peerlbl_active = selinux_peerlbl_enabled();
 
5199
5200	if (peerlbl_active) {
5201		/* This will return peer_sid = SECSID_NULL if there are
5202		 * no peer labels, see security_net_peersid_resolve().
5203		 */
5204		err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5205					      &peer_sid);
5206		if (err)
5207			return err;
5208
5209		if (peer_sid == SECSID_NULL)
5210			peer_sid = SECINITSID_UNLABELED;
 
 
5211	}
5212
5213	if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5214		sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5215
5216		/* Here as first association on socket. As the peer SID
5217		 * was allowed by peer recv (and the netif/node checks),
5218		 * then it is approved by policy and used as the primary
5219		 * peer SID for getpeercon(3).
5220		 */
5221		sksec->peer_sid = peer_sid;
5222	} else if  (sksec->peer_sid != peer_sid) {
5223		/* Other association peer SIDs are checked to enforce
5224		 * consistency among the peer SIDs.
5225		 */
5226		ad.type = LSM_AUDIT_DATA_NET;
5227		ad.u.net = &net;
5228		ad.u.net->sk = ep->base.sk;
5229		err = avc_has_perm(&selinux_state,
5230				   sksec->peer_sid, peer_sid, sksec->sclass,
5231				   SCTP_SOCKET__ASSOCIATION, &ad);
5232		if (err)
5233			return err;
5234	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5235
5236	/* Compute the MLS component for the connection and store
5237	 * the information in ep. This will be used by SCTP TCP type
5238	 * sockets and peeled off connections as they cause a new
5239	 * socket to be generated. selinux_sctp_sk_clone() will then
5240	 * plug this into the new socket.
5241	 */
5242	err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5243	if (err)
5244		return err;
5245
5246	ep->secid = conn_sid;
5247	ep->peer_secid = peer_sid;
5248
5249	/* Set any NetLabel labels including CIPSO/CALIPSO options. */
5250	return selinux_netlbl_sctp_assoc_request(ep, skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5251}
5252
5253/* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5254 * based on their @optname.
5255 */
5256static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5257				     struct sockaddr *address,
5258				     int addrlen)
5259{
5260	int len, err = 0, walk_size = 0;
5261	void *addr_buf;
5262	struct sockaddr *addr;
5263	struct socket *sock;
5264
5265	if (!selinux_policycap_extsockclass())
5266		return 0;
5267
5268	/* Process one or more addresses that may be IPv4 or IPv6 */
5269	sock = sk->sk_socket;
5270	addr_buf = address;
5271
5272	while (walk_size < addrlen) {
5273		if (walk_size + sizeof(sa_family_t) > addrlen)
5274			return -EINVAL;
5275
5276		addr = addr_buf;
5277		switch (addr->sa_family) {
5278		case AF_UNSPEC:
5279		case AF_INET:
5280			len = sizeof(struct sockaddr_in);
5281			break;
5282		case AF_INET6:
5283			len = sizeof(struct sockaddr_in6);
5284			break;
5285		default:
5286			return -EINVAL;
5287		}
5288
5289		if (walk_size + len > addrlen)
5290			return -EINVAL;
5291
5292		err = -EINVAL;
5293		switch (optname) {
5294		/* Bind checks */
5295		case SCTP_PRIMARY_ADDR:
5296		case SCTP_SET_PEER_PRIMARY_ADDR:
5297		case SCTP_SOCKOPT_BINDX_ADD:
5298			err = selinux_socket_bind(sock, addr, len);
5299			break;
5300		/* Connect checks */
5301		case SCTP_SOCKOPT_CONNECTX:
5302		case SCTP_PARAM_SET_PRIMARY:
5303		case SCTP_PARAM_ADD_IP:
5304		case SCTP_SENDMSG_CONNECT:
5305			err = selinux_socket_connect_helper(sock, addr, len);
5306			if (err)
5307				return err;
5308
5309			/* As selinux_sctp_bind_connect() is called by the
5310			 * SCTP protocol layer, the socket is already locked,
5311			 * therefore selinux_netlbl_socket_connect_locked() is
5312			 * is called here. The situations handled are:
5313			 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5314			 * whenever a new IP address is added or when a new
5315			 * primary address is selected.
5316			 * Note that an SCTP connect(2) call happens before
5317			 * the SCTP protocol layer and is handled via
5318			 * selinux_socket_connect().
5319			 */
5320			err = selinux_netlbl_socket_connect_locked(sk, addr);
5321			break;
5322		}
5323
5324		if (err)
5325			return err;
5326
5327		addr_buf += len;
5328		walk_size += len;
5329	}
5330
5331	return 0;
5332}
5333
5334/* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5335static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5336				  struct sock *newsk)
5337{
5338	struct sk_security_struct *sksec = sk->sk_security;
5339	struct sk_security_struct *newsksec = newsk->sk_security;
5340
5341	/* If policy does not support SECCLASS_SCTP_SOCKET then call
5342	 * the non-sctp clone version.
5343	 */
5344	if (!selinux_policycap_extsockclass())
5345		return selinux_sk_clone_security(sk, newsk);
5346
5347	newsksec->sid = ep->secid;
5348	newsksec->peer_sid = ep->peer_secid;
5349	newsksec->sclass = sksec->sclass;
5350	selinux_netlbl_sctp_sk_clone(sk, newsk);
5351}
5352
5353static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5354				     struct request_sock *req)
5355{
5356	struct sk_security_struct *sksec = sk->sk_security;
5357	int err;
5358	u16 family = req->rsk_ops->family;
5359	u32 connsid;
5360	u32 peersid;
5361
5362	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5363	if (err)
5364		return err;
5365	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5366	if (err)
5367		return err;
5368	req->secid = connsid;
5369	req->peer_secid = peersid;
5370
5371	return selinux_netlbl_inet_conn_request(req, family);
5372}
5373
5374static void selinux_inet_csk_clone(struct sock *newsk,
5375				   const struct request_sock *req)
5376{
5377	struct sk_security_struct *newsksec = newsk->sk_security;
5378
5379	newsksec->sid = req->secid;
5380	newsksec->peer_sid = req->peer_secid;
5381	/* NOTE: Ideally, we should also get the isec->sid for the
5382	   new socket in sync, but we don't have the isec available yet.
5383	   So we will wait until sock_graft to do it, by which
5384	   time it will have been created and available. */
5385
5386	/* We don't need to take any sort of lock here as we are the only
5387	 * thread with access to newsksec */
5388	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5389}
5390
5391static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5392{
5393	u16 family = sk->sk_family;
5394	struct sk_security_struct *sksec = sk->sk_security;
5395
5396	/* handle mapped IPv4 packets arriving via IPv6 sockets */
5397	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5398		family = PF_INET;
5399
5400	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5401}
5402
5403static int selinux_secmark_relabel_packet(u32 sid)
5404{
5405	const struct task_security_struct *__tsec;
5406	u32 tsid;
5407
5408	__tsec = selinux_cred(current_cred());
5409	tsid = __tsec->sid;
5410
5411	return avc_has_perm(&selinux_state,
5412			    tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5413			    NULL);
5414}
5415
5416static void selinux_secmark_refcount_inc(void)
5417{
5418	atomic_inc(&selinux_secmark_refcount);
5419}
5420
5421static void selinux_secmark_refcount_dec(void)
5422{
5423	atomic_dec(&selinux_secmark_refcount);
5424}
5425
5426static void selinux_req_classify_flow(const struct request_sock *req,
5427				      struct flowi *fl)
5428{
5429	fl->flowi_secid = req->secid;
5430}
5431
5432static int selinux_tun_dev_alloc_security(void **security)
5433{
5434	struct tun_security_struct *tunsec;
5435
5436	tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5437	if (!tunsec)
5438		return -ENOMEM;
5439	tunsec->sid = current_sid();
5440
5441	*security = tunsec;
5442	return 0;
5443}
5444
5445static void selinux_tun_dev_free_security(void *security)
5446{
5447	kfree(security);
5448}
5449
5450static int selinux_tun_dev_create(void)
5451{
5452	u32 sid = current_sid();
5453
5454	/* we aren't taking into account the "sockcreate" SID since the socket
5455	 * that is being created here is not a socket in the traditional sense,
5456	 * instead it is a private sock, accessible only to the kernel, and
5457	 * representing a wide range of network traffic spanning multiple
5458	 * connections unlike traditional sockets - check the TUN driver to
5459	 * get a better understanding of why this socket is special */
5460
5461	return avc_has_perm(&selinux_state,
5462			    sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5463			    NULL);
5464}
5465
5466static int selinux_tun_dev_attach_queue(void *security)
5467{
5468	struct tun_security_struct *tunsec = security;
5469
5470	return avc_has_perm(&selinux_state,
5471			    current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5472			    TUN_SOCKET__ATTACH_QUEUE, NULL);
5473}
5474
5475static int selinux_tun_dev_attach(struct sock *sk, void *security)
5476{
5477	struct tun_security_struct *tunsec = security;
5478	struct sk_security_struct *sksec = sk->sk_security;
5479
5480	/* we don't currently perform any NetLabel based labeling here and it
5481	 * isn't clear that we would want to do so anyway; while we could apply
5482	 * labeling without the support of the TUN user the resulting labeled
5483	 * traffic from the other end of the connection would almost certainly
5484	 * cause confusion to the TUN user that had no idea network labeling
5485	 * protocols were being used */
5486
5487	sksec->sid = tunsec->sid;
5488	sksec->sclass = SECCLASS_TUN_SOCKET;
5489
5490	return 0;
5491}
5492
5493static int selinux_tun_dev_open(void *security)
5494{
5495	struct tun_security_struct *tunsec = security;
5496	u32 sid = current_sid();
5497	int err;
5498
5499	err = avc_has_perm(&selinux_state,
5500			   sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5501			   TUN_SOCKET__RELABELFROM, NULL);
5502	if (err)
5503		return err;
5504	err = avc_has_perm(&selinux_state,
5505			   sid, sid, SECCLASS_TUN_SOCKET,
5506			   TUN_SOCKET__RELABELTO, NULL);
5507	if (err)
5508		return err;
5509	tunsec->sid = sid;
5510
5511	return 0;
5512}
5513
5514#ifdef CONFIG_NETFILTER
5515
5516static unsigned int selinux_ip_forward(struct sk_buff *skb,
5517				       const struct net_device *indev,
5518				       u16 family)
5519{
5520	int err;
 
5521	char *addrp;
5522	u32 peer_sid;
5523	struct common_audit_data ad;
5524	struct lsm_network_audit net = {0,};
5525	u8 secmark_active;
5526	u8 netlbl_active;
5527	u8 peerlbl_active;
5528
5529	if (!selinux_policycap_netpeer())
5530		return NF_ACCEPT;
5531
5532	secmark_active = selinux_secmark_enabled();
5533	netlbl_active = netlbl_enabled();
5534	peerlbl_active = selinux_peerlbl_enabled();
5535	if (!secmark_active && !peerlbl_active)
5536		return NF_ACCEPT;
5537
 
5538	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5539		return NF_DROP;
5540
5541	ad.type = LSM_AUDIT_DATA_NET;
5542	ad.u.net = &net;
5543	ad.u.net->netif = indev->ifindex;
5544	ad.u.net->family = family;
5545	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5546		return NF_DROP;
5547
5548	if (peerlbl_active) {
5549		err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
 
 
5550					       addrp, family, peer_sid, &ad);
5551		if (err) {
5552			selinux_netlbl_err(skb, family, err, 1);
5553			return NF_DROP;
5554		}
5555	}
5556
5557	if (secmark_active)
5558		if (avc_has_perm(&selinux_state,
5559				 peer_sid, skb->secmark,
5560				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5561			return NF_DROP;
5562
5563	if (netlbl_active)
5564		/* we do this in the FORWARD path and not the POST_ROUTING
5565		 * path because we want to make sure we apply the necessary
5566		 * labeling before IPsec is applied so we can leverage AH
5567		 * protection */
5568		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5569			return NF_DROP;
5570
5571	return NF_ACCEPT;
5572}
5573
5574static unsigned int selinux_ipv4_forward(void *priv,
5575					 struct sk_buff *skb,
5576					 const struct nf_hook_state *state)
5577{
5578	return selinux_ip_forward(skb, state->in, PF_INET);
5579}
5580
5581#if IS_ENABLED(CONFIG_IPV6)
5582static unsigned int selinux_ipv6_forward(void *priv,
5583					 struct sk_buff *skb,
5584					 const struct nf_hook_state *state)
5585{
5586	return selinux_ip_forward(skb, state->in, PF_INET6);
5587}
5588#endif	/* IPV6 */
5589
5590static unsigned int selinux_ip_output(struct sk_buff *skb,
5591				      u16 family)
5592{
5593	struct sock *sk;
5594	u32 sid;
5595
5596	if (!netlbl_enabled())
5597		return NF_ACCEPT;
5598
5599	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5600	 * because we want to make sure we apply the necessary labeling
5601	 * before IPsec is applied so we can leverage AH protection */
5602	sk = skb->sk;
5603	if (sk) {
5604		struct sk_security_struct *sksec;
5605
5606		if (sk_listener(sk))
5607			/* if the socket is the listening state then this
5608			 * packet is a SYN-ACK packet which means it needs to
5609			 * be labeled based on the connection/request_sock and
5610			 * not the parent socket.  unfortunately, we can't
5611			 * lookup the request_sock yet as it isn't queued on
5612			 * the parent socket until after the SYN-ACK is sent.
5613			 * the "solution" is to simply pass the packet as-is
5614			 * as any IP option based labeling should be copied
5615			 * from the initial connection request (in the IP
5616			 * layer).  it is far from ideal, but until we get a
5617			 * security label in the packet itself this is the
5618			 * best we can do. */
5619			return NF_ACCEPT;
5620
5621		/* standard practice, label using the parent socket */
5622		sksec = sk->sk_security;
5623		sid = sksec->sid;
5624	} else
5625		sid = SECINITSID_KERNEL;
5626	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5627		return NF_DROP;
5628
5629	return NF_ACCEPT;
5630}
5631
5632static unsigned int selinux_ipv4_output(void *priv,
5633					struct sk_buff *skb,
5634					const struct nf_hook_state *state)
5635{
5636	return selinux_ip_output(skb, PF_INET);
5637}
5638
5639#if IS_ENABLED(CONFIG_IPV6)
5640static unsigned int selinux_ipv6_output(void *priv,
5641					struct sk_buff *skb,
5642					const struct nf_hook_state *state)
5643{
5644	return selinux_ip_output(skb, PF_INET6);
5645}
5646#endif	/* IPV6 */
5647
5648static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5649						int ifindex,
5650						u16 family)
5651{
5652	struct sock *sk = skb_to_full_sk(skb);
5653	struct sk_security_struct *sksec;
5654	struct common_audit_data ad;
5655	struct lsm_network_audit net = {0,};
5656	char *addrp;
5657	u8 proto;
5658
 
5659	if (sk == NULL)
5660		return NF_ACCEPT;
5661	sksec = sk->sk_security;
5662
5663	ad.type = LSM_AUDIT_DATA_NET;
5664	ad.u.net = &net;
5665	ad.u.net->netif = ifindex;
5666	ad.u.net->family = family;
5667	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5668		return NF_DROP;
5669
5670	if (selinux_secmark_enabled())
5671		if (avc_has_perm(&selinux_state,
5672				 sksec->sid, skb->secmark,
5673				 SECCLASS_PACKET, PACKET__SEND, &ad))
5674			return NF_DROP_ERR(-ECONNREFUSED);
5675
5676	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5677		return NF_DROP_ERR(-ECONNREFUSED);
5678
5679	return NF_ACCEPT;
5680}
5681
5682static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5683					 const struct net_device *outdev,
5684					 u16 family)
5685{
 
5686	u32 secmark_perm;
5687	u32 peer_sid;
5688	int ifindex = outdev->ifindex;
5689	struct sock *sk;
5690	struct common_audit_data ad;
5691	struct lsm_network_audit net = {0,};
5692	char *addrp;
5693	u8 secmark_active;
5694	u8 peerlbl_active;
5695
5696	/* If any sort of compatibility mode is enabled then handoff processing
5697	 * to the selinux_ip_postroute_compat() function to deal with the
5698	 * special handling.  We do this in an attempt to keep this function
5699	 * as fast and as clean as possible. */
5700	if (!selinux_policycap_netpeer())
5701		return selinux_ip_postroute_compat(skb, ifindex, family);
5702
5703	secmark_active = selinux_secmark_enabled();
5704	peerlbl_active = selinux_peerlbl_enabled();
5705	if (!secmark_active && !peerlbl_active)
5706		return NF_ACCEPT;
5707
5708	sk = skb_to_full_sk(skb);
5709
5710#ifdef CONFIG_XFRM
5711	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5712	 * packet transformation so allow the packet to pass without any checks
5713	 * since we'll have another chance to perform access control checks
5714	 * when the packet is on it's final way out.
5715	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5716	 *       is NULL, in this case go ahead and apply access control.
5717	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5718	 *       TCP listening state we cannot wait until the XFRM processing
5719	 *       is done as we will miss out on the SA label if we do;
5720	 *       unfortunately, this means more work, but it is only once per
5721	 *       connection. */
5722	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5723	    !(sk && sk_listener(sk)))
5724		return NF_ACCEPT;
5725#endif
5726
 
5727	if (sk == NULL) {
5728		/* Without an associated socket the packet is either coming
5729		 * from the kernel or it is being forwarded; check the packet
5730		 * to determine which and if the packet is being forwarded
5731		 * query the packet directly to determine the security label. */
5732		if (skb->skb_iif) {
5733			secmark_perm = PACKET__FORWARD_OUT;
5734			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5735				return NF_DROP;
5736		} else {
5737			secmark_perm = PACKET__SEND;
5738			peer_sid = SECINITSID_KERNEL;
5739		}
5740	} else if (sk_listener(sk)) {
5741		/* Locally generated packet but the associated socket is in the
5742		 * listening state which means this is a SYN-ACK packet.  In
5743		 * this particular case the correct security label is assigned
5744		 * to the connection/request_sock but unfortunately we can't
5745		 * query the request_sock as it isn't queued on the parent
5746		 * socket until after the SYN-ACK packet is sent; the only
5747		 * viable choice is to regenerate the label like we do in
5748		 * selinux_inet_conn_request().  See also selinux_ip_output()
5749		 * for similar problems. */
5750		u32 skb_sid;
5751		struct sk_security_struct *sksec;
5752
5753		sksec = sk->sk_security;
5754		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5755			return NF_DROP;
5756		/* At this point, if the returned skb peerlbl is SECSID_NULL
5757		 * and the packet has been through at least one XFRM
5758		 * transformation then we must be dealing with the "final"
5759		 * form of labeled IPsec packet; since we've already applied
5760		 * all of our access controls on this packet we can safely
5761		 * pass the packet. */
5762		if (skb_sid == SECSID_NULL) {
5763			switch (family) {
5764			case PF_INET:
5765				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5766					return NF_ACCEPT;
5767				break;
5768			case PF_INET6:
5769				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5770					return NF_ACCEPT;
5771				break;
5772			default:
5773				return NF_DROP_ERR(-ECONNREFUSED);
5774			}
5775		}
5776		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5777			return NF_DROP;
5778		secmark_perm = PACKET__SEND;
5779	} else {
5780		/* Locally generated packet, fetch the security label from the
5781		 * associated socket. */
5782		struct sk_security_struct *sksec = sk->sk_security;
5783		peer_sid = sksec->sid;
5784		secmark_perm = PACKET__SEND;
5785	}
5786
5787	ad.type = LSM_AUDIT_DATA_NET;
5788	ad.u.net = &net;
5789	ad.u.net->netif = ifindex;
5790	ad.u.net->family = family;
5791	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5792		return NF_DROP;
5793
5794	if (secmark_active)
5795		if (avc_has_perm(&selinux_state,
5796				 peer_sid, skb->secmark,
5797				 SECCLASS_PACKET, secmark_perm, &ad))
5798			return NF_DROP_ERR(-ECONNREFUSED);
5799
5800	if (peerlbl_active) {
5801		u32 if_sid;
5802		u32 node_sid;
5803
5804		if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5805			return NF_DROP;
5806		if (avc_has_perm(&selinux_state,
5807				 peer_sid, if_sid,
5808				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5809			return NF_DROP_ERR(-ECONNREFUSED);
5810
5811		if (sel_netnode_sid(addrp, family, &node_sid))
5812			return NF_DROP;
5813		if (avc_has_perm(&selinux_state,
5814				 peer_sid, node_sid,
5815				 SECCLASS_NODE, NODE__SENDTO, &ad))
5816			return NF_DROP_ERR(-ECONNREFUSED);
5817	}
5818
5819	return NF_ACCEPT;
5820}
5821
5822static unsigned int selinux_ipv4_postroute(void *priv,
5823					   struct sk_buff *skb,
5824					   const struct nf_hook_state *state)
5825{
5826	return selinux_ip_postroute(skb, state->out, PF_INET);
5827}
5828
5829#if IS_ENABLED(CONFIG_IPV6)
5830static unsigned int selinux_ipv6_postroute(void *priv,
5831					   struct sk_buff *skb,
5832					   const struct nf_hook_state *state)
5833{
5834	return selinux_ip_postroute(skb, state->out, PF_INET6);
5835}
5836#endif	/* IPV6 */
5837
5838#endif	/* CONFIG_NETFILTER */
5839
5840static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5841{
5842	int rc = 0;
5843	unsigned int msg_len;
5844	unsigned int data_len = skb->len;
5845	unsigned char *data = skb->data;
5846	struct nlmsghdr *nlh;
5847	struct sk_security_struct *sksec = sk->sk_security;
5848	u16 sclass = sksec->sclass;
5849	u32 perm;
5850
5851	while (data_len >= nlmsg_total_size(0)) {
5852		nlh = (struct nlmsghdr *)data;
5853
5854		/* NOTE: the nlmsg_len field isn't reliably set by some netlink
5855		 *       users which means we can't reject skb's with bogus
5856		 *       length fields; our solution is to follow what
5857		 *       netlink_rcv_skb() does and simply skip processing at
5858		 *       messages with length fields that are clearly junk
5859		 */
5860		if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5861			return 0;
5862
5863		rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5864		if (rc == 0) {
5865			rc = sock_has_perm(sk, perm);
5866			if (rc)
5867				return rc;
5868		} else if (rc == -EINVAL) {
5869			/* -EINVAL is a missing msg/perm mapping */
5870			pr_warn_ratelimited("SELinux: unrecognized netlink"
5871				" message: protocol=%hu nlmsg_type=%hu sclass=%s"
5872				" pid=%d comm=%s\n",
5873				sk->sk_protocol, nlh->nlmsg_type,
5874				secclass_map[sclass - 1].name,
5875				task_pid_nr(current), current->comm);
5876			if (enforcing_enabled(&selinux_state) &&
5877			    !security_get_allow_unknown(&selinux_state))
5878				return rc;
5879			rc = 0;
5880		} else if (rc == -ENOENT) {
5881			/* -ENOENT is a missing socket/class mapping, ignore */
5882			rc = 0;
5883		} else {
5884			return rc;
5885		}
5886
5887		/* move to the next message after applying netlink padding */
5888		msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5889		if (msg_len >= data_len)
5890			return 0;
5891		data_len -= msg_len;
5892		data += msg_len;
5893	}
5894
5895	return rc;
5896}
5897
5898static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5899{
5900	isec->sclass = sclass;
5901	isec->sid = current_sid();
5902}
5903
5904static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5905			u32 perms)
5906{
5907	struct ipc_security_struct *isec;
5908	struct common_audit_data ad;
5909	u32 sid = current_sid();
5910
5911	isec = selinux_ipc(ipc_perms);
5912
5913	ad.type = LSM_AUDIT_DATA_IPC;
5914	ad.u.ipc_id = ipc_perms->key;
5915
5916	return avc_has_perm(&selinux_state,
5917			    sid, isec->sid, isec->sclass, perms, &ad);
5918}
5919
5920static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5921{
5922	struct msg_security_struct *msec;
5923
5924	msec = selinux_msg_msg(msg);
5925	msec->sid = SECINITSID_UNLABELED;
5926
5927	return 0;
5928}
5929
5930/* message queue security operations */
5931static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5932{
5933	struct ipc_security_struct *isec;
5934	struct common_audit_data ad;
5935	u32 sid = current_sid();
5936	int rc;
5937
5938	isec = selinux_ipc(msq);
5939	ipc_init_security(isec, SECCLASS_MSGQ);
5940
5941	ad.type = LSM_AUDIT_DATA_IPC;
5942	ad.u.ipc_id = msq->key;
5943
5944	rc = avc_has_perm(&selinux_state,
5945			  sid, isec->sid, SECCLASS_MSGQ,
5946			  MSGQ__CREATE, &ad);
5947	return rc;
5948}
5949
5950static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5951{
5952	struct ipc_security_struct *isec;
5953	struct common_audit_data ad;
5954	u32 sid = current_sid();
5955
5956	isec = selinux_ipc(msq);
5957
5958	ad.type = LSM_AUDIT_DATA_IPC;
5959	ad.u.ipc_id = msq->key;
5960
5961	return avc_has_perm(&selinux_state,
5962			    sid, isec->sid, SECCLASS_MSGQ,
5963			    MSGQ__ASSOCIATE, &ad);
5964}
5965
5966static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
5967{
5968	int err;
5969	int perms;
5970
5971	switch (cmd) {
5972	case IPC_INFO:
5973	case MSG_INFO:
5974		/* No specific object, just general system-wide information. */
5975		return avc_has_perm(&selinux_state,
5976				    current_sid(), SECINITSID_KERNEL,
5977				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
5978	case IPC_STAT:
5979	case MSG_STAT:
5980	case MSG_STAT_ANY:
5981		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5982		break;
5983	case IPC_SET:
5984		perms = MSGQ__SETATTR;
5985		break;
5986	case IPC_RMID:
5987		perms = MSGQ__DESTROY;
5988		break;
5989	default:
5990		return 0;
5991	}
5992
5993	err = ipc_has_perm(msq, perms);
5994	return err;
5995}
5996
5997static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
5998{
5999	struct ipc_security_struct *isec;
6000	struct msg_security_struct *msec;
6001	struct common_audit_data ad;
6002	u32 sid = current_sid();
6003	int rc;
6004
6005	isec = selinux_ipc(msq);
6006	msec = selinux_msg_msg(msg);
6007
6008	/*
6009	 * First time through, need to assign label to the message
6010	 */
6011	if (msec->sid == SECINITSID_UNLABELED) {
6012		/*
6013		 * Compute new sid based on current process and
6014		 * message queue this message will be stored in
6015		 */
6016		rc = security_transition_sid(&selinux_state, sid, isec->sid,
6017					     SECCLASS_MSG, NULL, &msec->sid);
6018		if (rc)
6019			return rc;
6020	}
6021
6022	ad.type = LSM_AUDIT_DATA_IPC;
6023	ad.u.ipc_id = msq->key;
6024
6025	/* Can this process write to the queue? */
6026	rc = avc_has_perm(&selinux_state,
6027			  sid, isec->sid, SECCLASS_MSGQ,
6028			  MSGQ__WRITE, &ad);
6029	if (!rc)
6030		/* Can this process send the message */
6031		rc = avc_has_perm(&selinux_state,
6032				  sid, msec->sid, SECCLASS_MSG,
6033				  MSG__SEND, &ad);
6034	if (!rc)
6035		/* Can the message be put in the queue? */
6036		rc = avc_has_perm(&selinux_state,
6037				  msec->sid, isec->sid, SECCLASS_MSGQ,
6038				  MSGQ__ENQUEUE, &ad);
6039
6040	return rc;
6041}
6042
6043static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6044				    struct task_struct *target,
6045				    long type, int mode)
6046{
6047	struct ipc_security_struct *isec;
6048	struct msg_security_struct *msec;
6049	struct common_audit_data ad;
6050	u32 sid = task_sid(target);
6051	int rc;
6052
6053	isec = selinux_ipc(msq);
6054	msec = selinux_msg_msg(msg);
6055
6056	ad.type = LSM_AUDIT_DATA_IPC;
6057	ad.u.ipc_id = msq->key;
6058
6059	rc = avc_has_perm(&selinux_state,
6060			  sid, isec->sid,
6061			  SECCLASS_MSGQ, MSGQ__READ, &ad);
6062	if (!rc)
6063		rc = avc_has_perm(&selinux_state,
6064				  sid, msec->sid,
6065				  SECCLASS_MSG, MSG__RECEIVE, &ad);
6066	return rc;
6067}
6068
6069/* Shared Memory security operations */
6070static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6071{
6072	struct ipc_security_struct *isec;
6073	struct common_audit_data ad;
6074	u32 sid = current_sid();
6075	int rc;
6076
6077	isec = selinux_ipc(shp);
6078	ipc_init_security(isec, SECCLASS_SHM);
6079
6080	ad.type = LSM_AUDIT_DATA_IPC;
6081	ad.u.ipc_id = shp->key;
6082
6083	rc = avc_has_perm(&selinux_state,
6084			  sid, isec->sid, SECCLASS_SHM,
6085			  SHM__CREATE, &ad);
6086	return rc;
6087}
6088
6089static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6090{
6091	struct ipc_security_struct *isec;
6092	struct common_audit_data ad;
6093	u32 sid = current_sid();
6094
6095	isec = selinux_ipc(shp);
6096
6097	ad.type = LSM_AUDIT_DATA_IPC;
6098	ad.u.ipc_id = shp->key;
6099
6100	return avc_has_perm(&selinux_state,
6101			    sid, isec->sid, SECCLASS_SHM,
6102			    SHM__ASSOCIATE, &ad);
6103}
6104
6105/* Note, at this point, shp is locked down */
6106static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6107{
6108	int perms;
6109	int err;
6110
6111	switch (cmd) {
6112	case IPC_INFO:
6113	case SHM_INFO:
6114		/* No specific object, just general system-wide information. */
6115		return avc_has_perm(&selinux_state,
6116				    current_sid(), SECINITSID_KERNEL,
6117				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6118	case IPC_STAT:
6119	case SHM_STAT:
6120	case SHM_STAT_ANY:
6121		perms = SHM__GETATTR | SHM__ASSOCIATE;
6122		break;
6123	case IPC_SET:
6124		perms = SHM__SETATTR;
6125		break;
6126	case SHM_LOCK:
6127	case SHM_UNLOCK:
6128		perms = SHM__LOCK;
6129		break;
6130	case IPC_RMID:
6131		perms = SHM__DESTROY;
6132		break;
6133	default:
6134		return 0;
6135	}
6136
6137	err = ipc_has_perm(shp, perms);
6138	return err;
6139}
6140
6141static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6142			     char __user *shmaddr, int shmflg)
6143{
6144	u32 perms;
6145
6146	if (shmflg & SHM_RDONLY)
6147		perms = SHM__READ;
6148	else
6149		perms = SHM__READ | SHM__WRITE;
6150
6151	return ipc_has_perm(shp, perms);
6152}
6153
6154/* Semaphore security operations */
6155static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6156{
6157	struct ipc_security_struct *isec;
6158	struct common_audit_data ad;
6159	u32 sid = current_sid();
6160	int rc;
6161
6162	isec = selinux_ipc(sma);
6163	ipc_init_security(isec, SECCLASS_SEM);
6164
6165	ad.type = LSM_AUDIT_DATA_IPC;
6166	ad.u.ipc_id = sma->key;
6167
6168	rc = avc_has_perm(&selinux_state,
6169			  sid, isec->sid, SECCLASS_SEM,
6170			  SEM__CREATE, &ad);
6171	return rc;
6172}
6173
6174static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6175{
6176	struct ipc_security_struct *isec;
6177	struct common_audit_data ad;
6178	u32 sid = current_sid();
6179
6180	isec = selinux_ipc(sma);
6181
6182	ad.type = LSM_AUDIT_DATA_IPC;
6183	ad.u.ipc_id = sma->key;
6184
6185	return avc_has_perm(&selinux_state,
6186			    sid, isec->sid, SECCLASS_SEM,
6187			    SEM__ASSOCIATE, &ad);
6188}
6189
6190/* Note, at this point, sma is locked down */
6191static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6192{
6193	int err;
6194	u32 perms;
6195
6196	switch (cmd) {
6197	case IPC_INFO:
6198	case SEM_INFO:
6199		/* No specific object, just general system-wide information. */
6200		return avc_has_perm(&selinux_state,
6201				    current_sid(), SECINITSID_KERNEL,
6202				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6203	case GETPID:
6204	case GETNCNT:
6205	case GETZCNT:
6206		perms = SEM__GETATTR;
6207		break;
6208	case GETVAL:
6209	case GETALL:
6210		perms = SEM__READ;
6211		break;
6212	case SETVAL:
6213	case SETALL:
6214		perms = SEM__WRITE;
6215		break;
6216	case IPC_RMID:
6217		perms = SEM__DESTROY;
6218		break;
6219	case IPC_SET:
6220		perms = SEM__SETATTR;
6221		break;
6222	case IPC_STAT:
6223	case SEM_STAT:
6224	case SEM_STAT_ANY:
6225		perms = SEM__GETATTR | SEM__ASSOCIATE;
6226		break;
6227	default:
6228		return 0;
6229	}
6230
6231	err = ipc_has_perm(sma, perms);
6232	return err;
6233}
6234
6235static int selinux_sem_semop(struct kern_ipc_perm *sma,
6236			     struct sembuf *sops, unsigned nsops, int alter)
6237{
6238	u32 perms;
6239
6240	if (alter)
6241		perms = SEM__READ | SEM__WRITE;
6242	else
6243		perms = SEM__READ;
6244
6245	return ipc_has_perm(sma, perms);
6246}
6247
6248static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6249{
6250	u32 av = 0;
6251
6252	av = 0;
6253	if (flag & S_IRUGO)
6254		av |= IPC__UNIX_READ;
6255	if (flag & S_IWUGO)
6256		av |= IPC__UNIX_WRITE;
6257
6258	if (av == 0)
6259		return 0;
6260
6261	return ipc_has_perm(ipcp, av);
6262}
6263
6264static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6265{
6266	struct ipc_security_struct *isec = selinux_ipc(ipcp);
6267	*secid = isec->sid;
6268}
6269
6270static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6271{
6272	if (inode)
6273		inode_doinit_with_dentry(inode, dentry);
6274}
6275
6276static int selinux_getprocattr(struct task_struct *p,
6277			       char *name, char **value)
6278{
6279	const struct task_security_struct *__tsec;
6280	u32 sid;
6281	int error;
6282	unsigned len;
6283
6284	rcu_read_lock();
6285	__tsec = selinux_cred(__task_cred(p));
6286
6287	if (current != p) {
6288		error = avc_has_perm(&selinux_state,
6289				     current_sid(), __tsec->sid,
6290				     SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6291		if (error)
6292			goto bad;
6293	}
6294
6295	if (!strcmp(name, "current"))
 
6296		sid = __tsec->sid;
6297	else if (!strcmp(name, "prev"))
 
6298		sid = __tsec->osid;
6299	else if (!strcmp(name, "exec"))
 
6300		sid = __tsec->exec_sid;
6301	else if (!strcmp(name, "fscreate"))
 
6302		sid = __tsec->create_sid;
6303	else if (!strcmp(name, "keycreate"))
 
6304		sid = __tsec->keycreate_sid;
6305	else if (!strcmp(name, "sockcreate"))
 
6306		sid = __tsec->sockcreate_sid;
6307	else {
6308		error = -EINVAL;
 
6309		goto bad;
6310	}
6311	rcu_read_unlock();
6312
6313	if (!sid)
6314		return 0;
6315
6316	error = security_sid_to_context(&selinux_state, sid, value, &len);
6317	if (error)
6318		return error;
6319	return len;
6320
6321bad:
6322	rcu_read_unlock();
6323	return error;
6324}
6325
6326static int selinux_setprocattr(const char *name, void *value, size_t size)
6327{
6328	struct task_security_struct *tsec;
6329	struct cred *new;
6330	u32 mysid = current_sid(), sid = 0, ptsid;
6331	int error;
6332	char *str = value;
6333
6334	/*
6335	 * Basic control over ability to set these attributes at all.
6336	 */
6337	if (!strcmp(name, "exec"))
6338		error = avc_has_perm(&selinux_state,
6339				     mysid, mysid, SECCLASS_PROCESS,
6340				     PROCESS__SETEXEC, NULL);
6341	else if (!strcmp(name, "fscreate"))
6342		error = avc_has_perm(&selinux_state,
6343				     mysid, mysid, SECCLASS_PROCESS,
6344				     PROCESS__SETFSCREATE, NULL);
6345	else if (!strcmp(name, "keycreate"))
6346		error = avc_has_perm(&selinux_state,
6347				     mysid, mysid, SECCLASS_PROCESS,
6348				     PROCESS__SETKEYCREATE, NULL);
6349	else if (!strcmp(name, "sockcreate"))
6350		error = avc_has_perm(&selinux_state,
6351				     mysid, mysid, SECCLASS_PROCESS,
6352				     PROCESS__SETSOCKCREATE, NULL);
6353	else if (!strcmp(name, "current"))
6354		error = avc_has_perm(&selinux_state,
6355				     mysid, mysid, SECCLASS_PROCESS,
6356				     PROCESS__SETCURRENT, NULL);
6357	else
6358		error = -EINVAL;
 
 
 
6359	if (error)
6360		return error;
6361
6362	/* Obtain a SID for the context, if one was specified. */
6363	if (size && str[0] && str[0] != '\n') {
6364		if (str[size-1] == '\n') {
6365			str[size-1] = 0;
6366			size--;
6367		}
6368		error = security_context_to_sid(&selinux_state, value, size,
6369						&sid, GFP_KERNEL);
6370		if (error == -EINVAL && !strcmp(name, "fscreate")) {
6371			if (!has_cap_mac_admin(true)) {
6372				struct audit_buffer *ab;
6373				size_t audit_size;
6374
6375				/* We strip a nul only if it is at the end, otherwise the
6376				 * context contains a nul and we should audit that */
 
6377				if (str[size - 1] == '\0')
6378					audit_size = size - 1;
6379				else
6380					audit_size = size;
6381				ab = audit_log_start(audit_context(),
6382						     GFP_ATOMIC,
6383						     AUDIT_SELINUX_ERR);
 
 
6384				audit_log_format(ab, "op=fscreate invalid_context=");
6385				audit_log_n_untrustedstring(ab, value, audit_size);
 
6386				audit_log_end(ab);
6387
6388				return error;
6389			}
6390			error = security_context_to_sid_force(
6391						      &selinux_state,
6392						      value, size, &sid);
6393		}
6394		if (error)
6395			return error;
6396	}
6397
6398	new = prepare_creds();
6399	if (!new)
6400		return -ENOMEM;
6401
6402	/* Permission checking based on the specified context is
6403	   performed during the actual operation (execve,
6404	   open/mkdir/...), when we know the full context of the
6405	   operation.  See selinux_bprm_creds_for_exec for the execve
6406	   checks and may_create for the file creation checks. The
6407	   operation will then fail if the context is not permitted. */
6408	tsec = selinux_cred(new);
6409	if (!strcmp(name, "exec")) {
6410		tsec->exec_sid = sid;
6411	} else if (!strcmp(name, "fscreate")) {
6412		tsec->create_sid = sid;
6413	} else if (!strcmp(name, "keycreate")) {
6414		if (sid) {
6415			error = avc_has_perm(&selinux_state, mysid, sid,
6416					     SECCLASS_KEY, KEY__CREATE, NULL);
6417			if (error)
6418				goto abort_change;
6419		}
6420		tsec->keycreate_sid = sid;
6421	} else if (!strcmp(name, "sockcreate")) {
6422		tsec->sockcreate_sid = sid;
6423	} else if (!strcmp(name, "current")) {
6424		error = -EINVAL;
6425		if (sid == 0)
6426			goto abort_change;
6427
6428		/* Only allow single threaded processes to change context */
6429		error = -EPERM;
6430		if (!current_is_single_threaded()) {
6431			error = security_bounded_transition(&selinux_state,
6432							    tsec->sid, sid);
6433			if (error)
6434				goto abort_change;
6435		}
6436
6437		/* Check permissions for the transition. */
6438		error = avc_has_perm(&selinux_state,
6439				     tsec->sid, sid, SECCLASS_PROCESS,
6440				     PROCESS__DYNTRANSITION, NULL);
6441		if (error)
6442			goto abort_change;
6443
6444		/* Check for ptracing, and update the task SID if ok.
6445		   Otherwise, leave SID unchanged and fail. */
6446		ptsid = ptrace_parent_sid();
6447		if (ptsid != 0) {
6448			error = avc_has_perm(&selinux_state,
6449					     ptsid, sid, SECCLASS_PROCESS,
6450					     PROCESS__PTRACE, NULL);
6451			if (error)
6452				goto abort_change;
6453		}
6454
6455		tsec->sid = sid;
6456	} else {
6457		error = -EINVAL;
6458		goto abort_change;
6459	}
6460
6461	commit_creds(new);
6462	return size;
6463
6464abort_change:
6465	abort_creds(new);
6466	return error;
6467}
6468
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6469static int selinux_ismaclabel(const char *name)
6470{
6471	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6472}
6473
6474static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6475{
6476	return security_sid_to_context(&selinux_state, secid,
6477				       secdata, seclen);
6478}
6479
6480static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6481{
6482	return security_context_to_sid(&selinux_state, secdata, seclen,
6483				       secid, GFP_KERNEL);
6484}
6485
6486static void selinux_release_secctx(char *secdata, u32 seclen)
6487{
6488	kfree(secdata);
6489}
6490
6491static void selinux_inode_invalidate_secctx(struct inode *inode)
6492{
6493	struct inode_security_struct *isec = selinux_inode(inode);
6494
6495	spin_lock(&isec->lock);
6496	isec->initialized = LABEL_INVALID;
6497	spin_unlock(&isec->lock);
6498}
6499
6500/*
6501 *	called with inode->i_mutex locked
6502 */
6503static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6504{
6505	int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6506					   ctx, ctxlen, 0);
6507	/* Do not return error when suppressing label (SBLABEL_MNT not set). */
6508	return rc == -EOPNOTSUPP ? 0 : rc;
6509}
6510
6511/*
6512 *	called with inode->i_mutex locked
6513 */
6514static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6515{
6516	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
 
6517}
6518
6519static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6520{
6521	int len = 0;
6522	len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6523						ctx, true);
6524	if (len < 0)
6525		return len;
6526	*ctxlen = len;
6527	return 0;
6528}
6529#ifdef CONFIG_KEYS
6530
6531static int selinux_key_alloc(struct key *k, const struct cred *cred,
6532			     unsigned long flags)
6533{
6534	const struct task_security_struct *tsec;
6535	struct key_security_struct *ksec;
6536
6537	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6538	if (!ksec)
6539		return -ENOMEM;
6540
6541	tsec = selinux_cred(cred);
6542	if (tsec->keycreate_sid)
6543		ksec->sid = tsec->keycreate_sid;
6544	else
6545		ksec->sid = tsec->sid;
6546
6547	k->security = ksec;
6548	return 0;
6549}
6550
6551static void selinux_key_free(struct key *k)
6552{
6553	struct key_security_struct *ksec = k->security;
6554
6555	k->security = NULL;
6556	kfree(ksec);
6557}
6558
6559static int selinux_key_permission(key_ref_t key_ref,
6560				  const struct cred *cred,
6561				  enum key_need_perm need_perm)
6562{
6563	struct key *key;
6564	struct key_security_struct *ksec;
6565	u32 perm, sid;
6566
6567	switch (need_perm) {
6568	case KEY_NEED_VIEW:
6569		perm = KEY__VIEW;
6570		break;
6571	case KEY_NEED_READ:
6572		perm = KEY__READ;
6573		break;
6574	case KEY_NEED_WRITE:
6575		perm = KEY__WRITE;
6576		break;
6577	case KEY_NEED_SEARCH:
6578		perm = KEY__SEARCH;
6579		break;
6580	case KEY_NEED_LINK:
6581		perm = KEY__LINK;
6582		break;
6583	case KEY_NEED_SETATTR:
6584		perm = KEY__SETATTR;
6585		break;
6586	case KEY_NEED_UNLINK:
6587	case KEY_SYSADMIN_OVERRIDE:
6588	case KEY_AUTHTOKEN_OVERRIDE:
6589	case KEY_DEFER_PERM_CHECK:
6590		return 0;
6591	default:
6592		WARN_ON(1);
6593		return -EPERM;
6594
6595	}
6596
6597	sid = cred_sid(cred);
6598	key = key_ref_to_ptr(key_ref);
6599	ksec = key->security;
6600
6601	return avc_has_perm(&selinux_state,
6602			    sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6603}
6604
6605static int selinux_key_getsecurity(struct key *key, char **_buffer)
6606{
6607	struct key_security_struct *ksec = key->security;
6608	char *context = NULL;
6609	unsigned len;
6610	int rc;
6611
6612	rc = security_sid_to_context(&selinux_state, ksec->sid,
6613				     &context, &len);
6614	if (!rc)
6615		rc = len;
6616	*_buffer = context;
6617	return rc;
6618}
6619
6620#ifdef CONFIG_KEY_NOTIFICATIONS
6621static int selinux_watch_key(struct key *key)
6622{
6623	struct key_security_struct *ksec = key->security;
6624	u32 sid = current_sid();
6625
6626	return avc_has_perm(&selinux_state,
6627			    sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6628}
6629#endif
6630#endif
6631
6632#ifdef CONFIG_SECURITY_INFINIBAND
6633static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6634{
6635	struct common_audit_data ad;
6636	int err;
6637	u32 sid = 0;
6638	struct ib_security_struct *sec = ib_sec;
6639	struct lsm_ibpkey_audit ibpkey;
6640
6641	err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6642	if (err)
6643		return err;
6644
6645	ad.type = LSM_AUDIT_DATA_IBPKEY;
6646	ibpkey.subnet_prefix = subnet_prefix;
6647	ibpkey.pkey = pkey_val;
6648	ad.u.ibpkey = &ibpkey;
6649	return avc_has_perm(&selinux_state,
6650			    sec->sid, sid,
6651			    SECCLASS_INFINIBAND_PKEY,
6652			    INFINIBAND_PKEY__ACCESS, &ad);
6653}
6654
6655static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6656					    u8 port_num)
6657{
6658	struct common_audit_data ad;
6659	int err;
6660	u32 sid = 0;
6661	struct ib_security_struct *sec = ib_sec;
6662	struct lsm_ibendport_audit ibendport;
6663
6664	err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6665				      &sid);
6666
6667	if (err)
6668		return err;
6669
6670	ad.type = LSM_AUDIT_DATA_IBENDPORT;
6671	strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6672	ibendport.port = port_num;
6673	ad.u.ibendport = &ibendport;
6674	return avc_has_perm(&selinux_state,
6675			    sec->sid, sid,
6676			    SECCLASS_INFINIBAND_ENDPORT,
6677			    INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6678}
6679
6680static int selinux_ib_alloc_security(void **ib_sec)
6681{
6682	struct ib_security_struct *sec;
6683
6684	sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6685	if (!sec)
6686		return -ENOMEM;
6687	sec->sid = current_sid();
6688
6689	*ib_sec = sec;
6690	return 0;
6691}
6692
6693static void selinux_ib_free_security(void *ib_sec)
6694{
6695	kfree(ib_sec);
6696}
6697#endif
6698
6699#ifdef CONFIG_BPF_SYSCALL
6700static int selinux_bpf(int cmd, union bpf_attr *attr,
6701				     unsigned int size)
6702{
6703	u32 sid = current_sid();
6704	int ret;
6705
6706	switch (cmd) {
6707	case BPF_MAP_CREATE:
6708		ret = avc_has_perm(&selinux_state,
6709				   sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6710				   NULL);
6711		break;
6712	case BPF_PROG_LOAD:
6713		ret = avc_has_perm(&selinux_state,
6714				   sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6715				   NULL);
6716		break;
6717	default:
6718		ret = 0;
6719		break;
6720	}
6721
6722	return ret;
6723}
6724
6725static u32 bpf_map_fmode_to_av(fmode_t fmode)
6726{
6727	u32 av = 0;
6728
6729	if (fmode & FMODE_READ)
6730		av |= BPF__MAP_READ;
6731	if (fmode & FMODE_WRITE)
6732		av |= BPF__MAP_WRITE;
6733	return av;
6734}
6735
6736/* This function will check the file pass through unix socket or binder to see
6737 * if it is a bpf related object. And apply correspinding checks on the bpf
6738 * object based on the type. The bpf maps and programs, not like other files and
6739 * socket, are using a shared anonymous inode inside the kernel as their inode.
6740 * So checking that inode cannot identify if the process have privilege to
6741 * access the bpf object and that's why we have to add this additional check in
6742 * selinux_file_receive and selinux_binder_transfer_files.
6743 */
6744static int bpf_fd_pass(struct file *file, u32 sid)
6745{
6746	struct bpf_security_struct *bpfsec;
6747	struct bpf_prog *prog;
6748	struct bpf_map *map;
6749	int ret;
6750
6751	if (file->f_op == &bpf_map_fops) {
6752		map = file->private_data;
6753		bpfsec = map->security;
6754		ret = avc_has_perm(&selinux_state,
6755				   sid, bpfsec->sid, SECCLASS_BPF,
6756				   bpf_map_fmode_to_av(file->f_mode), NULL);
6757		if (ret)
6758			return ret;
6759	} else if (file->f_op == &bpf_prog_fops) {
6760		prog = file->private_data;
6761		bpfsec = prog->aux->security;
6762		ret = avc_has_perm(&selinux_state,
6763				   sid, bpfsec->sid, SECCLASS_BPF,
6764				   BPF__PROG_RUN, NULL);
6765		if (ret)
6766			return ret;
6767	}
6768	return 0;
6769}
6770
6771static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6772{
6773	u32 sid = current_sid();
6774	struct bpf_security_struct *bpfsec;
6775
6776	bpfsec = map->security;
6777	return avc_has_perm(&selinux_state,
6778			    sid, bpfsec->sid, SECCLASS_BPF,
6779			    bpf_map_fmode_to_av(fmode), NULL);
6780}
6781
6782static int selinux_bpf_prog(struct bpf_prog *prog)
6783{
6784	u32 sid = current_sid();
6785	struct bpf_security_struct *bpfsec;
6786
6787	bpfsec = prog->aux->security;
6788	return avc_has_perm(&selinux_state,
6789			    sid, bpfsec->sid, SECCLASS_BPF,
6790			    BPF__PROG_RUN, NULL);
6791}
6792
6793static int selinux_bpf_map_alloc(struct bpf_map *map)
6794{
6795	struct bpf_security_struct *bpfsec;
6796
6797	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6798	if (!bpfsec)
6799		return -ENOMEM;
6800
6801	bpfsec->sid = current_sid();
6802	map->security = bpfsec;
6803
6804	return 0;
6805}
6806
6807static void selinux_bpf_map_free(struct bpf_map *map)
6808{
6809	struct bpf_security_struct *bpfsec = map->security;
6810
6811	map->security = NULL;
6812	kfree(bpfsec);
6813}
6814
6815static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6816{
6817	struct bpf_security_struct *bpfsec;
6818
6819	bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6820	if (!bpfsec)
6821		return -ENOMEM;
6822
6823	bpfsec->sid = current_sid();
6824	aux->security = bpfsec;
6825
6826	return 0;
6827}
6828
6829static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6830{
6831	struct bpf_security_struct *bpfsec = aux->security;
6832
6833	aux->security = NULL;
6834	kfree(bpfsec);
6835}
6836#endif
6837
6838static int selinux_lockdown(enum lockdown_reason what)
6839{
6840	struct common_audit_data ad;
6841	u32 sid = current_sid();
6842	int invalid_reason = (what <= LOCKDOWN_NONE) ||
6843			     (what == LOCKDOWN_INTEGRITY_MAX) ||
6844			     (what >= LOCKDOWN_CONFIDENTIALITY_MAX);
6845
6846	if (WARN(invalid_reason, "Invalid lockdown reason")) {
6847		audit_log(audit_context(),
6848			  GFP_ATOMIC, AUDIT_SELINUX_ERR,
6849			  "lockdown_reason=invalid");
6850		return -EINVAL;
6851	}
6852
6853	ad.type = LSM_AUDIT_DATA_LOCKDOWN;
6854	ad.u.reason = what;
6855
6856	if (what <= LOCKDOWN_INTEGRITY_MAX)
6857		return avc_has_perm(&selinux_state,
6858				    sid, sid, SECCLASS_LOCKDOWN,
6859				    LOCKDOWN__INTEGRITY, &ad);
6860	else
6861		return avc_has_perm(&selinux_state,
6862				    sid, sid, SECCLASS_LOCKDOWN,
6863				    LOCKDOWN__CONFIDENTIALITY, &ad);
6864}
6865
6866struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
6867	.lbs_cred = sizeof(struct task_security_struct),
6868	.lbs_file = sizeof(struct file_security_struct),
6869	.lbs_inode = sizeof(struct inode_security_struct),
6870	.lbs_ipc = sizeof(struct ipc_security_struct),
6871	.lbs_msg_msg = sizeof(struct msg_security_struct),
 
 
6872};
6873
6874#ifdef CONFIG_PERF_EVENTS
6875static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6876{
6877	u32 requested, sid = current_sid();
6878
6879	if (type == PERF_SECURITY_OPEN)
6880		requested = PERF_EVENT__OPEN;
6881	else if (type == PERF_SECURITY_CPU)
6882		requested = PERF_EVENT__CPU;
6883	else if (type == PERF_SECURITY_KERNEL)
6884		requested = PERF_EVENT__KERNEL;
6885	else if (type == PERF_SECURITY_TRACEPOINT)
6886		requested = PERF_EVENT__TRACEPOINT;
6887	else
6888		return -EINVAL;
6889
6890	return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT,
6891			    requested, NULL);
6892}
6893
6894static int selinux_perf_event_alloc(struct perf_event *event)
6895{
6896	struct perf_event_security_struct *perfsec;
6897
6898	perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
6899	if (!perfsec)
6900		return -ENOMEM;
6901
6902	perfsec->sid = current_sid();
6903	event->security = perfsec;
6904
6905	return 0;
6906}
6907
6908static void selinux_perf_event_free(struct perf_event *event)
6909{
6910	struct perf_event_security_struct *perfsec = event->security;
6911
6912	event->security = NULL;
6913	kfree(perfsec);
6914}
6915
6916static int selinux_perf_event_read(struct perf_event *event)
6917{
6918	struct perf_event_security_struct *perfsec = event->security;
6919	u32 sid = current_sid();
6920
6921	return avc_has_perm(&selinux_state, sid, perfsec->sid,
6922			    SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
6923}
6924
6925static int selinux_perf_event_write(struct perf_event *event)
6926{
6927	struct perf_event_security_struct *perfsec = event->security;
6928	u32 sid = current_sid();
6929
6930	return avc_has_perm(&selinux_state, sid, perfsec->sid,
6931			    SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
6932}
6933#endif
6934
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6935/*
6936 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
6937 * 1. any hooks that don't belong to (2.) or (3.) below,
6938 * 2. hooks that both access structures allocated by other hooks, and allocate
6939 *    structures that can be later accessed by other hooks (mostly "cloning"
6940 *    hooks),
6941 * 3. hooks that only allocate structures that can be later accessed by other
6942 *    hooks ("allocating" hooks).
6943 *
6944 * Please follow block comment delimiters in the list to keep this order.
6945 *
6946 * This ordering is needed for SELinux runtime disable to work at least somewhat
6947 * safely. Breaking the ordering rules above might lead to NULL pointer derefs
6948 * when disabling SELinux at runtime.
6949 */
6950static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6951	LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6952	LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6953	LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6954	LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6955
6956	LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6957	LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6958	LSM_HOOK_INIT(capget, selinux_capget),
6959	LSM_HOOK_INIT(capset, selinux_capset),
6960	LSM_HOOK_INIT(capable, selinux_capable),
6961	LSM_HOOK_INIT(quotactl, selinux_quotactl),
6962	LSM_HOOK_INIT(quota_on, selinux_quota_on),
6963	LSM_HOOK_INIT(syslog, selinux_syslog),
6964	LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6965
6966	LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6967
6968	LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
6969	LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6970	LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6971
6972	LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6973	LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
 
6974	LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6975	LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6976	LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6977	LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6978	LSM_HOOK_INIT(sb_mount, selinux_mount),
6979	LSM_HOOK_INIT(sb_umount, selinux_umount),
6980	LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6981	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6982
6983	LSM_HOOK_INIT(move_mount, selinux_move_mount),
6984
6985	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6986	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6987
6988	LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6989	LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
 
6990	LSM_HOOK_INIT(inode_create, selinux_inode_create),
6991	LSM_HOOK_INIT(inode_link, selinux_inode_link),
6992	LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6993	LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6994	LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6995	LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6996	LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6997	LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6998	LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6999	LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7000	LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7001	LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7002	LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7003	LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7004	LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7005	LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7006	LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7007	LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
 
 
 
7008	LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7009	LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7010	LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7011	LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7012	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7013	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7014	LSM_HOOK_INIT(path_notify, selinux_path_notify),
7015
7016	LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7017
7018	LSM_HOOK_INIT(file_permission, selinux_file_permission),
7019	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7020	LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
 
7021	LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7022	LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7023	LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7024	LSM_HOOK_INIT(file_lock, selinux_file_lock),
7025	LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7026	LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7027	LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7028	LSM_HOOK_INIT(file_receive, selinux_file_receive),
7029
7030	LSM_HOOK_INIT(file_open, selinux_file_open),
7031
7032	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7033	LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7034	LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7035	LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7036	LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7037	LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7038	LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7039	LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7040	LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7041	LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7042	LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7043	LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7044	LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
 
7045	LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7046	LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7047	LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7048	LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7049	LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7050	LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7051	LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7052	LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7053	LSM_HOOK_INIT(task_kill, selinux_task_kill),
7054	LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
 
7055
7056	LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7057	LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7058
7059	LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7060	LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7061	LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7062	LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7063
7064	LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7065	LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7066	LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7067
7068	LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7069	LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7070	LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7071
7072	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7073
 
 
7074	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7075	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7076
7077	LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7078	LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7079	LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7080	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7081	LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7082	LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7083
7084	LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7085	LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7086
7087	LSM_HOOK_INIT(socket_create, selinux_socket_create),
7088	LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7089	LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7090	LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7091	LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7092	LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7093	LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7094	LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7095	LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7096	LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7097	LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7098	LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7099	LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7100	LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7101	LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7102	LSM_HOOK_INIT(socket_getpeersec_stream,
7103			selinux_socket_getpeersec_stream),
7104	LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7105	LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7106	LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7107	LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7108	LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7109	LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7110	LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7111	LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
 
 
7112	LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7113	LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7114	LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7115	LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7116	LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7117	LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7118	LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7119	LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7120	LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7121	LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7122	LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7123	LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7124#ifdef CONFIG_SECURITY_INFINIBAND
7125	LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7126	LSM_HOOK_INIT(ib_endport_manage_subnet,
7127		      selinux_ib_endport_manage_subnet),
7128	LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7129#endif
7130#ifdef CONFIG_SECURITY_NETWORK_XFRM
7131	LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7132	LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7133	LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7134	LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7135	LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7136	LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7137			selinux_xfrm_state_pol_flow_match),
7138	LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7139#endif
7140
7141#ifdef CONFIG_KEYS
7142	LSM_HOOK_INIT(key_free, selinux_key_free),
7143	LSM_HOOK_INIT(key_permission, selinux_key_permission),
7144	LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7145#ifdef CONFIG_KEY_NOTIFICATIONS
7146	LSM_HOOK_INIT(watch_key, selinux_watch_key),
7147#endif
7148#endif
7149
7150#ifdef CONFIG_AUDIT
7151	LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7152	LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7153	LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7154#endif
7155
7156#ifdef CONFIG_BPF_SYSCALL
7157	LSM_HOOK_INIT(bpf, selinux_bpf),
7158	LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7159	LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7160	LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7161	LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7162#endif
7163
7164#ifdef CONFIG_PERF_EVENTS
7165	LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7166	LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7167	LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7168	LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7169#endif
7170
7171	LSM_HOOK_INIT(locked_down, selinux_lockdown),
 
 
 
 
7172
7173	/*
7174	 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7175	 */
 
7176	LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7177	LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7178	LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7179	LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
7180#ifdef CONFIG_SECURITY_NETWORK_XFRM
7181	LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7182#endif
7183
7184	/*
7185	 * PUT "ALLOCATING" HOOKS HERE
7186	 */
7187	LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7188	LSM_HOOK_INIT(msg_queue_alloc_security,
7189		      selinux_msg_queue_alloc_security),
7190	LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7191	LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7192	LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7193	LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7194	LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7195	LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7196	LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7197	LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7198#ifdef CONFIG_SECURITY_INFINIBAND
7199	LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7200#endif
7201#ifdef CONFIG_SECURITY_NETWORK_XFRM
7202	LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7203	LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7204	LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7205		      selinux_xfrm_state_alloc_acquire),
7206#endif
7207#ifdef CONFIG_KEYS
7208	LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7209#endif
7210#ifdef CONFIG_AUDIT
7211	LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7212#endif
7213#ifdef CONFIG_BPF_SYSCALL
7214	LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7215	LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7216#endif
7217#ifdef CONFIG_PERF_EVENTS
7218	LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7219#endif
7220};
7221
7222static __init int selinux_init(void)
7223{
7224	pr_info("SELinux:  Initializing.\n");
7225
7226	memset(&selinux_state, 0, sizeof(selinux_state));
7227	enforcing_set(&selinux_state, selinux_enforcing_boot);
7228	selinux_state.checkreqprot = selinux_checkreqprot_boot;
7229	selinux_ss_init(&selinux_state.ss);
7230	selinux_avc_init(&selinux_state.avc);
7231	mutex_init(&selinux_state.status_lock);
 
7232
7233	/* Set the security state for the initial task. */
7234	cred_init_security();
7235
7236	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
 
 
7237
7238	avc_init();
7239
7240	avtab_cache_init();
7241
7242	ebitmap_cache_init();
7243
7244	hashtab_cache_init();
7245
7246	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
 
7247
7248	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7249		panic("SELinux: Unable to register AVC netcache callback\n");
7250
7251	if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7252		panic("SELinux: Unable to register AVC LSM notifier callback\n");
7253
7254	if (selinux_enforcing_boot)
7255		pr_debug("SELinux:  Starting in enforcing mode\n");
7256	else
7257		pr_debug("SELinux:  Starting in permissive mode\n");
7258
7259	fs_validate_description("selinux", selinux_fs_parameters);
7260
7261	return 0;
7262}
7263
7264static void delayed_superblock_init(struct super_block *sb, void *unused)
7265{
7266	selinux_set_mnt_opts(sb, NULL, 0, NULL);
7267}
7268
7269void selinux_complete_init(void)
7270{
7271	pr_debug("SELinux:  Completing initialization.\n");
7272
7273	/* Set up any superblocks initialized prior to the policy load. */
7274	pr_debug("SELinux:  Setting up existing superblocks.\n");
7275	iterate_supers(delayed_superblock_init, NULL);
7276}
7277
7278/* SELinux requires early initialization in order to label
7279   all processes and objects when they are created. */
7280DEFINE_LSM(selinux) = {
7281	.name = "selinux",
7282	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7283	.enabled = &selinux_enabled_boot,
7284	.blobs = &selinux_blob_sizes,
7285	.init = selinux_init,
7286};
7287
7288#if defined(CONFIG_NETFILTER)
7289
7290static const struct nf_hook_ops selinux_nf_ops[] = {
7291	{
7292		.hook =		selinux_ipv4_postroute,
7293		.pf =		NFPROTO_IPV4,
7294		.hooknum =	NF_INET_POST_ROUTING,
7295		.priority =	NF_IP_PRI_SELINUX_LAST,
7296	},
7297	{
7298		.hook =		selinux_ipv4_forward,
7299		.pf =		NFPROTO_IPV4,
7300		.hooknum =	NF_INET_FORWARD,
7301		.priority =	NF_IP_PRI_SELINUX_FIRST,
7302	},
7303	{
7304		.hook =		selinux_ipv4_output,
7305		.pf =		NFPROTO_IPV4,
7306		.hooknum =	NF_INET_LOCAL_OUT,
7307		.priority =	NF_IP_PRI_SELINUX_FIRST,
7308	},
7309#if IS_ENABLED(CONFIG_IPV6)
7310	{
7311		.hook =		selinux_ipv6_postroute,
7312		.pf =		NFPROTO_IPV6,
7313		.hooknum =	NF_INET_POST_ROUTING,
7314		.priority =	NF_IP6_PRI_SELINUX_LAST,
7315	},
7316	{
7317		.hook =		selinux_ipv6_forward,
7318		.pf =		NFPROTO_IPV6,
7319		.hooknum =	NF_INET_FORWARD,
7320		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7321	},
7322	{
7323		.hook =		selinux_ipv6_output,
7324		.pf =		NFPROTO_IPV6,
7325		.hooknum =	NF_INET_LOCAL_OUT,
7326		.priority =	NF_IP6_PRI_SELINUX_FIRST,
7327	},
7328#endif	/* IPV6 */
7329};
7330
7331static int __net_init selinux_nf_register(struct net *net)
7332{
7333	return nf_register_net_hooks(net, selinux_nf_ops,
7334				     ARRAY_SIZE(selinux_nf_ops));
7335}
7336
7337static void __net_exit selinux_nf_unregister(struct net *net)
7338{
7339	nf_unregister_net_hooks(net, selinux_nf_ops,
7340				ARRAY_SIZE(selinux_nf_ops));
7341}
7342
7343static struct pernet_operations selinux_net_ops = {
7344	.init = selinux_nf_register,
7345	.exit = selinux_nf_unregister,
7346};
7347
7348static int __init selinux_nf_ip_init(void)
7349{
7350	int err;
7351
7352	if (!selinux_enabled_boot)
7353		return 0;
7354
7355	pr_debug("SELinux:  Registering netfilter hooks\n");
7356
7357	err = register_pernet_subsys(&selinux_net_ops);
7358	if (err)
7359		panic("SELinux: register_pernet_subsys: error %d\n", err);
7360
7361	return 0;
7362}
7363__initcall(selinux_nf_ip_init);
7364
7365#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7366static void selinux_nf_ip_exit(void)
7367{
7368	pr_debug("SELinux:  Unregistering netfilter hooks\n");
7369
7370	unregister_pernet_subsys(&selinux_net_ops);
7371}
7372#endif
7373
7374#else /* CONFIG_NETFILTER */
7375
7376#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7377#define selinux_nf_ip_exit()
7378#endif
7379
7380#endif /* CONFIG_NETFILTER */
7381
7382#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7383int selinux_disable(struct selinux_state *state)
7384{
7385	if (selinux_initialized(state)) {
7386		/* Not permitted after initial policy load. */
7387		return -EINVAL;
7388	}
7389
7390	if (selinux_disabled(state)) {
7391		/* Only do this once. */
7392		return -EINVAL;
7393	}
7394
7395	selinux_mark_disabled(state);
7396
7397	pr_info("SELinux:  Disabled at runtime.\n");
7398
7399	/*
7400	 * Unregister netfilter hooks.
7401	 * Must be done before security_delete_hooks() to avoid breaking
7402	 * runtime disable.
7403	 */
7404	selinux_nf_ip_exit();
7405
7406	security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7407
7408	/* Try to destroy the avc node cache */
7409	avc_disable();
7410
7411	/* Unregister selinuxfs. */
7412	exit_sel_fs();
7413
7414	return 0;
7415}
7416#endif