1// SPDX-License-Identifier: GPL-2.0-only
   2/* Updated: Karl MacMillan <kmacmillan@tresys.com>
   3 *
   4 *	Added conditional policy language extensions
   5 *
   6 *  Updated: Hewlett-Packard <paul@paul-moore.com>
   7 *
   8 *	Added support for the policy capability bitmap
   9 *
  10 * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
  11 * Copyright (C) 2003 - 2004 Tresys Technology, LLC
  12 * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
 
 
 
  13 */
  14
  15#include <linux/kernel.h>
  16#include <linux/pagemap.h>
  17#include <linux/slab.h>
  18#include <linux/vmalloc.h>
  19#include <linux/fs.h>
  20#include <linux/fs_context.h>
  21#include <linux/mount.h>
  22#include <linux/mutex.h>
  23#include <linux/namei.h>
  24#include <linux/init.h>
  25#include <linux/string.h>
  26#include <linux/security.h>
  27#include <linux/major.h>
  28#include <linux/seq_file.h>
  29#include <linux/percpu.h>
  30#include <linux/audit.h>
  31#include <linux/uaccess.h>
  32#include <linux/kobject.h>
  33#include <linux/ctype.h>
  34
  35/* selinuxfs pseudo filesystem for exporting the security policy API.
  36   Based on the proc code and the fs/nfsd/nfsctl.c code. */
  37
  38#include "flask.h"
  39#include "avc.h"
  40#include "avc_ss.h"
  41#include "security.h"
  42#include "objsec.h"
  43#include "conditional.h"
  44#include "ima.h"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  45
  46enum sel_inos {
  47	SEL_ROOT_INO = 2,
  48	SEL_LOAD,	/* load policy */
  49	SEL_ENFORCE,	/* get or set enforcing status */
  50	SEL_CONTEXT,	/* validate context */
  51	SEL_ACCESS,	/* compute access decision */
  52	SEL_CREATE,	/* compute create labeling decision */
  53	SEL_RELABEL,	/* compute relabeling decision */
  54	SEL_USER,	/* compute reachable user contexts */
  55	SEL_POLICYVERS,	/* return policy version for this kernel */
  56	SEL_COMMIT_BOOLS, /* commit new boolean values */
  57	SEL_MLS,	/* return if MLS policy is enabled */
  58	SEL_DISABLE,	/* disable SELinux until next reboot */
  59	SEL_MEMBER,	/* compute polyinstantiation membership decision */
  60	SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
  61	SEL_COMPAT_NET,	/* whether to use old compat network packet controls */
  62	SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
  63	SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
  64	SEL_STATUS,	/* export current status using mmap() */
  65	SEL_POLICY,	/* allow userspace to read the in kernel policy */
  66	SEL_VALIDATE_TRANS, /* compute validatetrans decision */
  67	SEL_INO_NEXT,	/* The next inode number to use */
  68};
  69
  70struct selinux_fs_info {
  71	struct dentry *bool_dir;
  72	unsigned int bool_num;
  73	char **bool_pending_names;
  74	int *bool_pending_values;
  75	struct dentry *class_dir;
  76	unsigned long last_class_ino;
  77	bool policy_opened;
  78	struct dentry *policycap_dir;
  79	unsigned long last_ino;
  80	struct super_block *sb;
  81};
  82
  83static int selinux_fs_info_create(struct super_block *sb)
  84{
  85	struct selinux_fs_info *fsi;
  86
  87	fsi = kzalloc(sizeof(*fsi), GFP_KERNEL);
  88	if (!fsi)
  89		return -ENOMEM;
  90
  91	fsi->last_ino = SEL_INO_NEXT - 1;
  92	fsi->sb = sb;
  93	sb->s_fs_info = fsi;
  94	return 0;
  95}
  96
  97static void selinux_fs_info_free(struct super_block *sb)
  98{
  99	struct selinux_fs_info *fsi = sb->s_fs_info;
 100	unsigned int i;
 101
 102	if (fsi) {
 103		for (i = 0; i < fsi->bool_num; i++)
 104			kfree(fsi->bool_pending_names[i]);
 105		kfree(fsi->bool_pending_names);
 106		kfree(fsi->bool_pending_values);
 107	}
 108	kfree(sb->s_fs_info);
 109	sb->s_fs_info = NULL;
 110}
 111
 112#define SEL_INITCON_INO_OFFSET		0x01000000
 113#define SEL_BOOL_INO_OFFSET		0x02000000
 114#define SEL_CLASS_INO_OFFSET		0x04000000
 115#define SEL_POLICYCAP_INO_OFFSET	0x08000000
 116#define SEL_INO_MASK			0x00ffffff
 117
 118#define BOOL_DIR_NAME "booleans"
 119#define CLASS_DIR_NAME "class"
 120#define POLICYCAP_DIR_NAME "policy_capabilities"
 121
 122#define TMPBUFLEN	12
 123static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
 124				size_t count, loff_t *ppos)
 125{
 126	char tmpbuf[TMPBUFLEN];
 127	ssize_t length;
 128
 129	length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 130			   enforcing_enabled());
 131	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 132}
 133
 134#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 135static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
 136				 size_t count, loff_t *ppos)
 137
 138{
 139	char *page = NULL;
 140	ssize_t length;
 141	int scan_value;
 142	bool old_value, new_value;
 143
 144	if (count >= PAGE_SIZE)
 145		return -ENOMEM;
 146
 147	/* No partial writes. */
 148	if (*ppos != 0)
 149		return -EINVAL;
 150
 151	page = memdup_user_nul(buf, count);
 152	if (IS_ERR(page))
 153		return PTR_ERR(page);
 154
 155	length = -EINVAL;
 156	if (sscanf(page, "%d", &scan_value) != 1)
 157		goto out;
 158
 159	new_value = !!scan_value;
 160
 161	old_value = enforcing_enabled();
 162	if (new_value != old_value) {
 163		length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 164				      SECCLASS_SECURITY, SECURITY__SETENFORCE,
 165				      NULL);
 166		if (length)
 167			goto out;
 168		audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
 169			"enforcing=%d old_enforcing=%d auid=%u ses=%u"
 170			" enabled=1 old-enabled=1 lsm=selinux res=1",
 171			new_value, old_value,
 172			from_kuid(&init_user_ns, audit_get_loginuid(current)),
 173			audit_get_sessionid(current));
 174		enforcing_set(new_value);
 175		if (new_value)
 176			avc_ss_reset(0);
 177		selnl_notify_setenforce(new_value);
 178		selinux_status_update_setenforce(new_value);
 179		if (!new_value)
 180			call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 181
 182		selinux_ima_measure_state();
 183	}
 184	length = count;
 185out:
 186	kfree(page);
 187	return length;
 188}
 189#else
 190#define sel_write_enforce NULL
 191#endif
 192
 193static const struct file_operations sel_enforce_ops = {
 194	.read		= sel_read_enforce,
 195	.write		= sel_write_enforce,
 196	.llseek		= generic_file_llseek,
 197};
 198
 199static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 200					size_t count, loff_t *ppos)
 201{
 202	char tmpbuf[TMPBUFLEN];
 203	ssize_t length;
 204	ino_t ino = file_inode(filp)->i_ino;
 205	int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
 206		security_get_reject_unknown() :
 207		!security_get_allow_unknown();
 208
 209	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
 210	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 211}
 212
 213static const struct file_operations sel_handle_unknown_ops = {
 214	.read		= sel_read_handle_unknown,
 215	.llseek		= generic_file_llseek,
 216};
 217
 218static int sel_open_handle_status(struct inode *inode, struct file *filp)
 219{
 220	struct page    *status = selinux_kernel_status_page();
 221
 222	if (!status)
 223		return -ENOMEM;
 224
 225	filp->private_data = status;
 226
 227	return 0;
 228}
 229
 230static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
 231				      size_t count, loff_t *ppos)
 232{
 233	struct page    *status = filp->private_data;
 234
 235	BUG_ON(!status);
 236
 237	return simple_read_from_buffer(buf, count, ppos,
 238				       page_address(status),
 239				       sizeof(struct selinux_kernel_status));
 240}
 241
 242static int sel_mmap_handle_status(struct file *filp,
 243				  struct vm_area_struct *vma)
 244{
 245	struct page    *status = filp->private_data;
 246	unsigned long	size = vma->vm_end - vma->vm_start;
 247
 248	BUG_ON(!status);
 249
 250	/* only allows one page from the head */
 251	if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
 252		return -EIO;
 253	/* disallow writable mapping */
 254	if (vma->vm_flags & VM_WRITE)
 255		return -EPERM;
 256	/* disallow mprotect() turns it into writable */
 257	vm_flags_clear(vma, VM_MAYWRITE);
 258
 259	return remap_pfn_range(vma, vma->vm_start,
 260			       page_to_pfn(status),
 261			       size, vma->vm_page_prot);
 262}
 263
 264static const struct file_operations sel_handle_status_ops = {
 265	.open		= sel_open_handle_status,
 266	.read		= sel_read_handle_status,
 267	.mmap		= sel_mmap_handle_status,
 268	.llseek		= generic_file_llseek,
 269};
 270
 
 271static ssize_t sel_write_disable(struct file *file, const char __user *buf,
 272				 size_t count, loff_t *ppos)
 273
 274{
 275	char *page;
 276	ssize_t length;
 277	int new_value;
 278
 279	if (count >= PAGE_SIZE)
 280		return -ENOMEM;
 281
 282	/* No partial writes. */
 283	if (*ppos != 0)
 284		return -EINVAL;
 285
 286	page = memdup_user_nul(buf, count);
 287	if (IS_ERR(page))
 288		return PTR_ERR(page);
 289
 290	if (sscanf(page, "%d", &new_value) != 1) {
 291		length = -EINVAL;
 292		goto out;
 293	}
 294	length = count;
 295
 296	if (new_value) {
 297		pr_err("SELinux: https://github.com/SELinuxProject/selinux-kernel/wiki/DEPRECATE-runtime-disable\n");
 298		pr_err("SELinux: Runtime disable is not supported, use selinux=0 on the kernel cmdline.\n");
 
 
 
 
 
 299	}
 300
 
 301out:
 302	kfree(page);
 303	return length;
 304}
 
 
 
 305
 306static const struct file_operations sel_disable_ops = {
 307	.write		= sel_write_disable,
 308	.llseek		= generic_file_llseek,
 309};
 310
 311static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 312				   size_t count, loff_t *ppos)
 313{
 314	char tmpbuf[TMPBUFLEN];
 315	ssize_t length;
 316
 317	length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 318	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 319}
 320
 321static const struct file_operations sel_policyvers_ops = {
 322	.read		= sel_read_policyvers,
 323	.llseek		= generic_file_llseek,
 324};
 325
 326/* declaration for sel_write_load */
 327static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
 328			  unsigned int *bool_num, char ***bool_pending_names,
 329			  int **bool_pending_values);
 330static int sel_make_classes(struct selinux_policy *newpolicy,
 331			    struct dentry *class_dir,
 332			    unsigned long *last_class_ino);
 333
 334/* declaration for sel_make_class_dirs */
 335static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
 336			unsigned long *ino);
 337
 338/* declaration for sel_make_policy_nodes */
 339static struct dentry *sel_make_swapover_dir(struct super_block *sb,
 340						unsigned long *ino);
 341
 342static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 343				size_t count, loff_t *ppos)
 344{
 345	char tmpbuf[TMPBUFLEN];
 346	ssize_t length;
 347
 348	length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 349			   security_mls_enabled());
 350	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 351}
 352
 353static const struct file_operations sel_mls_ops = {
 354	.read		= sel_read_mls,
 355	.llseek		= generic_file_llseek,
 356};
 357
 358struct policy_load_memory {
 359	size_t len;
 360	void *data;
 361};
 362
 363static int sel_open_policy(struct inode *inode, struct file *filp)
 364{
 365	struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
 366	struct policy_load_memory *plm = NULL;
 367	int rc;
 368
 369	BUG_ON(filp->private_data);
 370
 371	mutex_lock(&selinux_state.policy_mutex);
 372
 373	rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 374			  SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 375	if (rc)
 376		goto err;
 377
 378	rc = -EBUSY;
 379	if (fsi->policy_opened)
 380		goto err;
 381
 382	rc = -ENOMEM;
 383	plm = kzalloc(sizeof(*plm), GFP_KERNEL);
 384	if (!plm)
 385		goto err;
 386
 387	rc = security_read_policy(&plm->data, &plm->len);
 388	if (rc)
 389		goto err;
 390
 391	if ((size_t)i_size_read(inode) != plm->len) {
 392		inode_lock(inode);
 393		i_size_write(inode, plm->len);
 394		inode_unlock(inode);
 395	}
 396
 397	fsi->policy_opened = 1;
 
 
 
 
 398
 399	filp->private_data = plm;
 400
 401	mutex_unlock(&selinux_state.policy_mutex);
 402
 403	return 0;
 404err:
 405	mutex_unlock(&selinux_state.policy_mutex);
 406
 407	if (plm)
 408		vfree(plm->data);
 409	kfree(plm);
 410	return rc;
 411}
 412
 413static int sel_release_policy(struct inode *inode, struct file *filp)
 414{
 415	struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
 416	struct policy_load_memory *plm = filp->private_data;
 417
 418	BUG_ON(!plm);
 419
 420	fsi->policy_opened = 0;
 421
 422	vfree(plm->data);
 423	kfree(plm);
 424
 425	return 0;
 426}
 427
 428static ssize_t sel_read_policy(struct file *filp, char __user *buf,
 429			       size_t count, loff_t *ppos)
 430{
 431	struct policy_load_memory *plm = filp->private_data;
 432	int ret;
 433
 434	ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 435			  SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 
 436	if (ret)
 437		return ret;
 438
 439	return simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
 
 
 
 440}
 441
 442static vm_fault_t sel_mmap_policy_fault(struct vm_fault *vmf)
 
 443{
 444	struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
 445	unsigned long offset;
 446	struct page *page;
 447
 448	if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
 449		return VM_FAULT_SIGBUS;
 450
 451	offset = vmf->pgoff << PAGE_SHIFT;
 452	if (offset >= roundup(plm->len, PAGE_SIZE))
 453		return VM_FAULT_SIGBUS;
 454
 455	page = vmalloc_to_page(plm->data + offset);
 456	get_page(page);
 457
 458	vmf->page = page;
 459
 460	return 0;
 461}
 462
 463static const struct vm_operations_struct sel_mmap_policy_ops = {
 464	.fault = sel_mmap_policy_fault,
 465	.page_mkwrite = sel_mmap_policy_fault,
 466};
 467
 468static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
 469{
 470	if (vma->vm_flags & VM_SHARED) {
 471		/* do not allow mprotect to make mapping writable */
 472		vm_flags_clear(vma, VM_MAYWRITE);
 473
 474		if (vma->vm_flags & VM_WRITE)
 475			return -EACCES;
 476	}
 477
 478	vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
 479	vma->vm_ops = &sel_mmap_policy_ops;
 480
 481	return 0;
 482}
 483
 484static const struct file_operations sel_policy_ops = {
 485	.open		= sel_open_policy,
 486	.read		= sel_read_policy,
 487	.mmap		= sel_mmap_policy,
 488	.release	= sel_release_policy,
 489	.llseek		= generic_file_llseek,
 490};
 491
 492static void sel_remove_old_bool_data(unsigned int bool_num, char **bool_names,
 493				     int *bool_values)
 494{
 495	u32 i;
 496
 497	/* bool_dir cleanup */
 498	for (i = 0; i < bool_num; i++)
 499		kfree(bool_names[i]);
 500	kfree(bool_names);
 501	kfree(bool_values);
 502}
 503
 504static int sel_make_policy_nodes(struct selinux_fs_info *fsi,
 505				struct selinux_policy *newpolicy)
 506{
 507	int ret = 0;
 508	struct dentry *tmp_parent, *tmp_bool_dir, *tmp_class_dir;
 509	unsigned int bool_num = 0;
 510	char **bool_names = NULL;
 511	int *bool_values = NULL;
 512	unsigned long tmp_ino = fsi->last_ino; /* Don't increment last_ino in this function */
 513
 514	tmp_parent = sel_make_swapover_dir(fsi->sb, &tmp_ino);
 515	if (IS_ERR(tmp_parent))
 516		return PTR_ERR(tmp_parent);
 517
 518	tmp_ino = fsi->bool_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
 519	tmp_bool_dir = sel_make_dir(tmp_parent, BOOL_DIR_NAME, &tmp_ino);
 520	if (IS_ERR(tmp_bool_dir)) {
 521		ret = PTR_ERR(tmp_bool_dir);
 522		goto out;
 523	}
 524
 525	tmp_ino = fsi->class_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
 526	tmp_class_dir = sel_make_dir(tmp_parent, CLASS_DIR_NAME, &tmp_ino);
 527	if (IS_ERR(tmp_class_dir)) {
 528		ret = PTR_ERR(tmp_class_dir);
 529		goto out;
 530	}
 531
 532	ret = sel_make_bools(newpolicy, tmp_bool_dir, &bool_num,
 533			     &bool_names, &bool_values);
 534	if (ret)
 535		goto out;
 536
 537	ret = sel_make_classes(newpolicy, tmp_class_dir,
 538			       &fsi->last_class_ino);
 539	if (ret)
 540		goto out;
 541
 542	lock_rename(tmp_parent, fsi->sb->s_root);
 543
 544	/* booleans */
 545	d_exchange(tmp_bool_dir, fsi->bool_dir);
 546
 547	swap(fsi->bool_num, bool_num);
 548	swap(fsi->bool_pending_names, bool_names);
 549	swap(fsi->bool_pending_values, bool_values);
 550
 551	fsi->bool_dir = tmp_bool_dir;
 552
 553	/* classes */
 554	d_exchange(tmp_class_dir, fsi->class_dir);
 555	fsi->class_dir = tmp_class_dir;
 556
 557	unlock_rename(tmp_parent, fsi->sb->s_root);
 558
 559out:
 560	sel_remove_old_bool_data(bool_num, bool_names, bool_values);
 561	/* Since the other temporary dirs are children of tmp_parent
 562	 * this will handle all the cleanup in the case of a failure before
 563	 * the swapover
 564	 */
 565	simple_recursive_removal(tmp_parent, NULL);
 566
 567	return ret;
 568}
 569
 570static ssize_t sel_write_load(struct file *file, const char __user *buf,
 571			      size_t count, loff_t *ppos)
 572
 573{
 574	struct selinux_fs_info *fsi;
 575	struct selinux_load_state load_state;
 576	ssize_t length;
 577	void *data = NULL;
 578
 579	/* no partial writes */
 580	if (*ppos)
 581		return -EINVAL;
 582	/* no empty policies */
 583	if (!count)
 584		return -EINVAL;
 585
 586	mutex_lock(&selinux_state.policy_mutex);
 587
 588	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 589			      SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
 590	if (length)
 591		goto out;
 592
 593	data = vmalloc(count);
 594	if (!data) {
 595		length = -ENOMEM;
 596		goto out;
 597	}
 598	if (copy_from_user(data, buf, count) != 0) {
 599		length = -EFAULT;
 600		goto out;
 601	}
 602
 603	length = security_load_policy(data, count, &load_state);
 604	if (length) {
 605		pr_warn_ratelimited("SELinux: failed to load policy\n");
 606		goto out;
 607	}
 608	fsi = file_inode(file)->i_sb->s_fs_info;
 609	length = sel_make_policy_nodes(fsi, load_state.policy);
 610	if (length) {
 611		pr_warn_ratelimited("SELinux: failed to initialize selinuxfs\n");
 612		selinux_policy_cancel(&load_state);
 613		goto out;
 614	}
 615
 616	selinux_policy_commit(&load_state);
 617	length = count;
 618	audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 619		"auid=%u ses=%u lsm=selinux res=1",
 
 
 620		from_kuid(&init_user_ns, audit_get_loginuid(current)),
 621		audit_get_sessionid(current));
 622
 623out:
 624	mutex_unlock(&selinux_state.policy_mutex);
 625	vfree(data);
 626	return length;
 627}
 628
 629static const struct file_operations sel_load_ops = {
 630	.write		= sel_write_load,
 631	.llseek		= generic_file_llseek,
 632};
 633
 634static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
 635{
 636	char *canon = NULL;
 637	u32 sid, len;
 638	ssize_t length;
 639
 640	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 641			      SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
 642	if (length)
 643		goto out;
 644
 645	length = security_context_to_sid(buf, size, &sid, GFP_KERNEL);
 646	if (length)
 647		goto out;
 648
 649	length = security_sid_to_context(sid, &canon, &len);
 650	if (length)
 651		goto out;
 652
 653	length = -ERANGE;
 654	if (len > SIMPLE_TRANSACTION_LIMIT) {
 655		pr_err("SELinux: %s:  context size (%u) exceeds "
 656			"payload max\n", __func__, len);
 657		goto out;
 658	}
 659
 660	memcpy(buf, canon, len);
 661	length = len;
 662out:
 663	kfree(canon);
 664	return length;
 665}
 666
 667static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 668				     size_t count, loff_t *ppos)
 669{
 670	char tmpbuf[TMPBUFLEN];
 671	ssize_t length;
 672
 673	length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
 674			   checkreqprot_get());
 675	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 676}
 677
 678static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
 679				      size_t count, loff_t *ppos)
 680{
 681	char *page;
 682	ssize_t length;
 683	unsigned int new_value;
 684
 685	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 686			      SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
 687			      NULL);
 688	if (length)
 689		return length;
 690
 691	if (count >= PAGE_SIZE)
 692		return -ENOMEM;
 693
 694	/* No partial writes. */
 695	if (*ppos != 0)
 696		return -EINVAL;
 697
 698	page = memdup_user_nul(buf, count);
 699	if (IS_ERR(page))
 700		return PTR_ERR(page);
 701
 702	if (sscanf(page, "%u", &new_value) != 1) {
 703		length = -EINVAL;
 704		goto out;
 705	}
 706	length = count;
 707
 708	if (new_value) {
 709		char comm[sizeof(current->comm)];
 710
 711		strscpy(comm, current->comm);
 712		pr_err("SELinux: %s (%d) set checkreqprot to 1. This is no longer supported.\n",
 713		       comm, current->pid);
 714	}
 715
 716	selinux_ima_measure_state();
 717
 
 
 718out:
 719	kfree(page);
 720	return length;
 721}
 722static const struct file_operations sel_checkreqprot_ops = {
 723	.read		= sel_read_checkreqprot,
 724	.write		= sel_write_checkreqprot,
 725	.llseek		= generic_file_llseek,
 726};
 727
 728static ssize_t sel_write_validatetrans(struct file *file,
 729					const char __user *buf,
 730					size_t count, loff_t *ppos)
 731{
 732	char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
 733	char *req = NULL;
 734	u32 osid, nsid, tsid;
 735	u16 tclass;
 736	int rc;
 737
 738	rc = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 739			  SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
 740	if (rc)
 741		goto out;
 742
 743	rc = -ENOMEM;
 744	if (count >= PAGE_SIZE)
 745		goto out;
 746
 747	/* No partial writes. */
 748	rc = -EINVAL;
 749	if (*ppos != 0)
 750		goto out;
 751
 752	req = memdup_user_nul(buf, count);
 753	if (IS_ERR(req)) {
 754		rc = PTR_ERR(req);
 755		req = NULL;
 
 
 
 756		goto out;
 757	}
 758
 759	rc = -ENOMEM;
 760	oldcon = kzalloc(count + 1, GFP_KERNEL);
 761	if (!oldcon)
 762		goto out;
 763
 764	newcon = kzalloc(count + 1, GFP_KERNEL);
 765	if (!newcon)
 766		goto out;
 767
 768	taskcon = kzalloc(count + 1, GFP_KERNEL);
 769	if (!taskcon)
 770		goto out;
 771
 772	rc = -EINVAL;
 773	if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
 774		goto out;
 775
 776	rc = security_context_str_to_sid(oldcon, &osid, GFP_KERNEL);
 777	if (rc)
 778		goto out;
 779
 780	rc = security_context_str_to_sid(newcon, &nsid, GFP_KERNEL);
 781	if (rc)
 782		goto out;
 783
 784	rc = security_context_str_to_sid(taskcon, &tsid, GFP_KERNEL);
 785	if (rc)
 786		goto out;
 787
 788	rc = security_validate_transition_user(osid, nsid, tsid, tclass);
 789	if (!rc)
 790		rc = count;
 791out:
 792	kfree(req);
 793	kfree(oldcon);
 794	kfree(newcon);
 795	kfree(taskcon);
 796	return rc;
 797}
 798
 799static const struct file_operations sel_transition_ops = {
 800	.write		= sel_write_validatetrans,
 801	.llseek		= generic_file_llseek,
 802};
 803
 804/*
 805 * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 806 */
 807static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 808static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 809static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 810static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 811static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 812
 813static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
 814	[SEL_ACCESS] = sel_write_access,
 815	[SEL_CREATE] = sel_write_create,
 816	[SEL_RELABEL] = sel_write_relabel,
 817	[SEL_USER] = sel_write_user,
 818	[SEL_MEMBER] = sel_write_member,
 819	[SEL_CONTEXT] = sel_write_context,
 820};
 821
 822static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 823{
 824	ino_t ino = file_inode(file)->i_ino;
 825	char *data;
 826	ssize_t rv;
 827
 828	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 829		return -EINVAL;
 830
 831	data = simple_transaction_get(file, buf, size);
 832	if (IS_ERR(data))
 833		return PTR_ERR(data);
 834
 835	rv = write_op[ino](file, data, size);
 836	if (rv > 0) {
 837		simple_transaction_set(file, rv);
 838		rv = size;
 839	}
 840	return rv;
 841}
 842
 843static const struct file_operations transaction_ops = {
 844	.write		= selinux_transaction_write,
 845	.read		= simple_transaction_read,
 846	.release	= simple_transaction_release,
 847	.llseek		= generic_file_llseek,
 848};
 849
 850/*
 851 * payload - write methods
 852 * If the method has a response, the response should be put in buf,
 853 * and the length returned.  Otherwise return 0 or and -error.
 854 */
 855
 856static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
 857{
 858	char *scon = NULL, *tcon = NULL;
 859	u32 ssid, tsid;
 860	u16 tclass;
 861	struct av_decision avd;
 862	ssize_t length;
 863
 864	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 865			      SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
 866	if (length)
 867		goto out;
 868
 869	length = -ENOMEM;
 870	scon = kzalloc(size + 1, GFP_KERNEL);
 871	if (!scon)
 872		goto out;
 873
 874	length = -ENOMEM;
 875	tcon = kzalloc(size + 1, GFP_KERNEL);
 876	if (!tcon)
 877		goto out;
 878
 879	length = -EINVAL;
 880	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 881		goto out;
 882
 883	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
 884	if (length)
 885		goto out;
 886
 887	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
 888	if (length)
 889		goto out;
 890
 891	security_compute_av_user(ssid, tsid, tclass, &avd);
 892
 893	length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 894			  "%x %x %x %x %u %x",
 895			  avd.allowed, 0xffffffff,
 896			  avd.auditallow, avd.auditdeny,
 897			  avd.seqno, avd.flags);
 898out:
 899	kfree(tcon);
 900	kfree(scon);
 901	return length;
 902}
 903
 904static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 905{
 906	char *scon = NULL, *tcon = NULL;
 907	char *namebuf = NULL, *objname = NULL;
 908	u32 ssid, tsid, newsid;
 909	u16 tclass;
 910	ssize_t length;
 911	char *newcon = NULL;
 912	u32 len;
 913	int nargs;
 914
 915	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
 916			      SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
 917			      NULL);
 918	if (length)
 919		goto out;
 920
 921	length = -ENOMEM;
 922	scon = kzalloc(size + 1, GFP_KERNEL);
 923	if (!scon)
 924		goto out;
 925
 926	length = -ENOMEM;
 927	tcon = kzalloc(size + 1, GFP_KERNEL);
 928	if (!tcon)
 929		goto out;
 930
 931	length = -ENOMEM;
 932	namebuf = kzalloc(size + 1, GFP_KERNEL);
 933	if (!namebuf)
 934		goto out;
 935
 936	length = -EINVAL;
 937	nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
 938	if (nargs < 3 || nargs > 4)
 939		goto out;
 940	if (nargs == 4) {
 941		/*
 942		 * If and when the name of new object to be queried contains
 943		 * either whitespace or multibyte characters, they shall be
 944		 * encoded based on the percentage-encoding rule.
 945		 * If not encoded, the sscanf logic picks up only left-half
 946		 * of the supplied name; split by a whitespace unexpectedly.
 947		 */
 948		char   *r, *w;
 949		int     c1, c2;
 950
 951		r = w = namebuf;
 952		do {
 953			c1 = *r++;
 954			if (c1 == '+')
 955				c1 = ' ';
 956			else if (c1 == '%') {
 957				c1 = hex_to_bin(*r++);
 958				if (c1 < 0)
 959					goto out;
 960				c2 = hex_to_bin(*r++);
 961				if (c2 < 0)
 962					goto out;
 963				c1 = (c1 << 4) | c2;
 964			}
 965			*w++ = c1;
 966		} while (c1 != '\0');
 967
 968		objname = namebuf;
 969	}
 970
 971	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
 972	if (length)
 973		goto out;
 974
 975	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
 976	if (length)
 977		goto out;
 978
 979	length = security_transition_sid_user(ssid, tsid, tclass,
 980					      objname, &newsid);
 981	if (length)
 982		goto out;
 983
 984	length = security_sid_to_context(newsid, &newcon, &len);
 985	if (length)
 986		goto out;
 987
 988	length = -ERANGE;
 989	if (len > SIMPLE_TRANSACTION_LIMIT) {
 990		pr_err("SELinux: %s:  context size (%u) exceeds "
 991			"payload max\n", __func__, len);
 992		goto out;
 993	}
 994
 995	memcpy(buf, newcon, len);
 996	length = len;
 997out:
 998	kfree(newcon);
 999	kfree(namebuf);
1000	kfree(tcon);
1001	kfree(scon);
1002	return length;
1003}
1004
1005static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
1006{
1007	char *scon = NULL, *tcon = NULL;
1008	u32 ssid, tsid, newsid;
1009	u16 tclass;
1010	ssize_t length;
1011	char *newcon = NULL;
1012	u32 len;
1013
1014	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1015			      SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
1016			      NULL);
1017	if (length)
1018		goto out;
1019
1020	length = -ENOMEM;
1021	scon = kzalloc(size + 1, GFP_KERNEL);
1022	if (!scon)
1023		goto out;
1024
1025	length = -ENOMEM;
1026	tcon = kzalloc(size + 1, GFP_KERNEL);
1027	if (!tcon)
1028		goto out;
1029
1030	length = -EINVAL;
1031	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1032		goto out;
1033
1034	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
1035	if (length)
1036		goto out;
1037
1038	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
1039	if (length)
1040		goto out;
1041
1042	length = security_change_sid(ssid, tsid, tclass, &newsid);
1043	if (length)
1044		goto out;
1045
1046	length = security_sid_to_context(newsid, &newcon, &len);
1047	if (length)
1048		goto out;
1049
1050	length = -ERANGE;
1051	if (len > SIMPLE_TRANSACTION_LIMIT)
1052		goto out;
1053
1054	memcpy(buf, newcon, len);
1055	length = len;
1056out:
1057	kfree(newcon);
1058	kfree(tcon);
1059	kfree(scon);
1060	return length;
1061}
1062
1063static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
1064{
1065	char *con = NULL, *user = NULL, *ptr;
1066	u32 sid, *sids = NULL;
1067	ssize_t length;
1068	char *newcon;
1069	int rc;
1070	u32 i, len, nsids;
1071
1072	pr_warn_ratelimited("SELinux: %s (%d) wrote to /sys/fs/selinux/user!"
1073		" This will not be supported in the future; please update your"
1074		" userspace.\n", current->comm, current->pid);
1075
1076	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1077			      SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
1078			      NULL);
1079	if (length)
1080		goto out;
1081
1082	length = -ENOMEM;
1083	con = kzalloc(size + 1, GFP_KERNEL);
1084	if (!con)
1085		goto out;
1086
1087	length = -ENOMEM;
1088	user = kzalloc(size + 1, GFP_KERNEL);
1089	if (!user)
1090		goto out;
1091
1092	length = -EINVAL;
1093	if (sscanf(buf, "%s %s", con, user) != 2)
1094		goto out;
1095
1096	length = security_context_str_to_sid(con, &sid, GFP_KERNEL);
1097	if (length)
1098		goto out;
1099
1100	length = security_get_user_sids(sid, user, &sids, &nsids);
1101	if (length)
1102		goto out;
1103
1104	length = sprintf(buf, "%u", nsids) + 1;
1105	ptr = buf + length;
1106	for (i = 0; i < nsids; i++) {
1107		rc = security_sid_to_context(sids[i], &newcon, &len);
1108		if (rc) {
1109			length = rc;
1110			goto out;
1111		}
1112		if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1113			kfree(newcon);
1114			length = -ERANGE;
1115			goto out;
1116		}
1117		memcpy(ptr, newcon, len);
1118		kfree(newcon);
1119		ptr += len;
1120		length += len;
1121	}
1122out:
1123	kfree(sids);
1124	kfree(user);
1125	kfree(con);
1126	return length;
1127}
1128
1129static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1130{
1131	char *scon = NULL, *tcon = NULL;
1132	u32 ssid, tsid, newsid;
1133	u16 tclass;
1134	ssize_t length;
1135	char *newcon = NULL;
1136	u32 len;
1137
1138	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1139			      SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1140			      NULL);
1141	if (length)
1142		goto out;
1143
1144	length = -ENOMEM;
1145	scon = kzalloc(size + 1, GFP_KERNEL);
1146	if (!scon)
1147		goto out;
1148
1149	length = -ENOMEM;
1150	tcon = kzalloc(size + 1, GFP_KERNEL);
1151	if (!tcon)
1152		goto out;
1153
1154	length = -EINVAL;
1155	if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1156		goto out;
1157
1158	length = security_context_str_to_sid(scon, &ssid, GFP_KERNEL);
1159	if (length)
1160		goto out;
1161
1162	length = security_context_str_to_sid(tcon, &tsid, GFP_KERNEL);
1163	if (length)
1164		goto out;
1165
1166	length = security_member_sid(ssid, tsid, tclass, &newsid);
1167	if (length)
1168		goto out;
1169
1170	length = security_sid_to_context(newsid, &newcon, &len);
1171	if (length)
1172		goto out;
1173
1174	length = -ERANGE;
1175	if (len > SIMPLE_TRANSACTION_LIMIT) {
1176		pr_err("SELinux: %s:  context size (%u) exceeds "
1177			"payload max\n", __func__, len);
1178		goto out;
1179	}
1180
1181	memcpy(buf, newcon, len);
1182	length = len;
1183out:
1184	kfree(newcon);
1185	kfree(tcon);
1186	kfree(scon);
1187	return length;
1188}
1189
1190static struct inode *sel_make_inode(struct super_block *sb, umode_t mode)
1191{
1192	struct inode *ret = new_inode(sb);
1193
1194	if (ret) {
1195		ret->i_mode = mode;
1196		simple_inode_init_ts(ret);
1197	}
1198	return ret;
1199}
1200
1201static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1202			     size_t count, loff_t *ppos)
1203{
1204	struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1205	char *page = NULL;
1206	ssize_t length;
1207	ssize_t ret;
1208	int cur_enforcing;
1209	unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1210	const char *name = filep->f_path.dentry->d_name.name;
1211
1212	mutex_lock(&selinux_state.policy_mutex);
1213
1214	ret = -EINVAL;
1215	if (index >= fsi->bool_num || strcmp(name,
1216					     fsi->bool_pending_names[index]))
1217		goto out_unlock;
1218
1219	ret = -ENOMEM;
1220	page = (char *)get_zeroed_page(GFP_KERNEL);
1221	if (!page)
1222		goto out_unlock;
1223
1224	cur_enforcing = security_get_bool_value(index);
1225	if (cur_enforcing < 0) {
1226		ret = cur_enforcing;
1227		goto out_unlock;
1228	}
1229	length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1230			  fsi->bool_pending_values[index]);
1231	mutex_unlock(&selinux_state.policy_mutex);
1232	ret = simple_read_from_buffer(buf, count, ppos, page, length);
1233out_free:
 
1234	free_page((unsigned long)page);
1235	return ret;
1236
1237out_unlock:
1238	mutex_unlock(&selinux_state.policy_mutex);
1239	goto out_free;
1240}
1241
1242static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1243			      size_t count, loff_t *ppos)
1244{
1245	struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1246	char *page = NULL;
1247	ssize_t length;
1248	int new_value;
1249	unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1250	const char *name = filep->f_path.dentry->d_name.name;
1251
1252	if (count >= PAGE_SIZE)
1253		return -ENOMEM;
1254
1255	/* No partial writes. */
1256	if (*ppos != 0)
1257		return -EINVAL;
1258
1259	page = memdup_user_nul(buf, count);
1260	if (IS_ERR(page))
1261		return PTR_ERR(page);
1262
1263	mutex_lock(&selinux_state.policy_mutex);
 
 
1264
1265	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1266			      SECCLASS_SECURITY, SECURITY__SETBOOL,
1267			      NULL);
1268	if (length)
1269		goto out;
1270
 
1271	length = -EINVAL;
1272	if (index >= fsi->bool_num || strcmp(name,
1273					     fsi->bool_pending_names[index]))
1274		goto out;
1275
 
 
 
 
 
 
 
1276	length = -EINVAL;
1277	if (sscanf(page, "%d", &new_value) != 1)
1278		goto out;
1279
1280	if (new_value)
1281		new_value = 1;
1282
1283	fsi->bool_pending_values[index] = new_value;
1284	length = count;
1285
1286out:
1287	mutex_unlock(&selinux_state.policy_mutex);
1288	kfree(page);
1289	return length;
1290}
1291
1292static const struct file_operations sel_bool_ops = {
1293	.read		= sel_read_bool,
1294	.write		= sel_write_bool,
1295	.llseek		= generic_file_llseek,
1296};
1297
1298static ssize_t sel_commit_bools_write(struct file *filep,
1299				      const char __user *buf,
1300				      size_t count, loff_t *ppos)
1301{
1302	struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1303	char *page = NULL;
1304	ssize_t length;
1305	int new_value;
1306
 
 
 
 
 
 
 
1307	if (count >= PAGE_SIZE)
1308		return -ENOMEM;
1309
1310	/* No partial writes. */
 
1311	if (*ppos != 0)
1312		return -EINVAL;
1313
1314	page = memdup_user_nul(buf, count);
1315	if (IS_ERR(page))
1316		return PTR_ERR(page);
1317
1318	mutex_lock(&selinux_state.policy_mutex);
1319
1320	length = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1321			      SECCLASS_SECURITY, SECURITY__SETBOOL,
1322			      NULL);
1323	if (length)
1324		goto out;
 
1325
1326	length = -EINVAL;
1327	if (sscanf(page, "%d", &new_value) != 1)
1328		goto out;
1329
1330	length = 0;
1331	if (new_value && fsi->bool_pending_values)
1332		length = security_set_bools(fsi->bool_num,
1333					    fsi->bool_pending_values);
1334
1335	if (!length)
1336		length = count;
1337
1338out:
1339	mutex_unlock(&selinux_state.policy_mutex);
1340	kfree(page);
1341	return length;
1342}
1343
1344static const struct file_operations sel_commit_bools_ops = {
1345	.write		= sel_commit_bools_write,
1346	.llseek		= generic_file_llseek,
1347};
1348
1349static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
1350			  unsigned int *bool_num, char ***bool_pending_names,
1351			  int **bool_pending_values)
1352{
1353	int ret;
1354	char **names, *page;
1355	u32 i, num;
1356
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1357	page = (char *)get_zeroed_page(GFP_KERNEL);
1358	if (!page)
1359		return -ENOMEM;
1360
1361	ret = security_get_bools(newpolicy, &num, &names, bool_pending_values);
1362	if (ret)
1363		goto out;
1364
1365	*bool_num = num;
1366	*bool_pending_names = names;
1367
1368	for (i = 0; i < num; i++) {
1369		struct dentry *dentry;
1370		struct inode *inode;
1371		struct inode_security_struct *isec;
1372		ssize_t len;
1373		u32 sid;
1374
1375		len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1376		if (len >= PAGE_SIZE) {
1377			ret = -ENAMETOOLONG;
1378			break;
1379		}
1380		dentry = d_alloc_name(bool_dir, names[i]);
1381		if (!dentry) {
1382			ret = -ENOMEM;
1383			break;
1384		}
1385
1386		inode = sel_make_inode(bool_dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1387		if (!inode) {
1388			dput(dentry);
1389			ret = -ENOMEM;
1390			break;
1391		}
1392
1393		isec = selinux_inode(inode);
1394		ret = selinux_policy_genfs_sid(newpolicy, "selinuxfs", page,
1395					 SECCLASS_FILE, &sid);
1396		if (ret) {
1397			pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1398					   page);
1399			sid = SECINITSID_SECURITY;
1400		}
1401
1402		isec->sid = sid;
1403		isec->initialized = LABEL_INITIALIZED;
1404		inode->i_fop = &sel_bool_ops;
1405		inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1406		d_add(dentry, inode);
1407	}
 
 
 
 
 
 
1408out:
1409	free_page((unsigned long)page);
 
 
 
 
 
 
 
 
 
1410	return ret;
1411}
1412
 
 
 
 
1413static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1414					    size_t count, loff_t *ppos)
1415{
1416	char tmpbuf[TMPBUFLEN];
1417	ssize_t length;
1418
1419	length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1420			   avc_get_cache_threshold());
1421	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1422}
1423
1424static ssize_t sel_write_avc_cache_threshold(struct file *file,
1425					     const char __user *buf,
1426					     size_t count, loff_t *ppos)
1427
1428{
1429	char *page;
1430	ssize_t ret;
1431	unsigned int new_value;
1432
1433	ret = avc_has_perm(current_sid(), SECINITSID_SECURITY,
1434			   SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1435			   NULL);
1436	if (ret)
1437		return ret;
1438
1439	if (count >= PAGE_SIZE)
1440		return -ENOMEM;
1441
1442	/* No partial writes. */
1443	if (*ppos != 0)
1444		return -EINVAL;
1445
1446	page = memdup_user_nul(buf, count);
1447	if (IS_ERR(page))
1448		return PTR_ERR(page);
1449
1450	ret = -EINVAL;
1451	if (sscanf(page, "%u", &new_value) != 1)
1452		goto out;
1453
1454	avc_set_cache_threshold(new_value);
1455
1456	ret = count;
1457out:
1458	kfree(page);
1459	return ret;
1460}
1461
1462static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1463				       size_t count, loff_t *ppos)
1464{
1465	char *page;
1466	ssize_t length;
1467
1468	page = (char *)__get_free_page(GFP_KERNEL);
1469	if (!page)
1470		return -ENOMEM;
1471
1472	length = avc_get_hash_stats(page);
1473	if (length >= 0)
1474		length = simple_read_from_buffer(buf, count, ppos, page, length);
1475	free_page((unsigned long)page);
1476
1477	return length;
1478}
1479
1480static ssize_t sel_read_sidtab_hash_stats(struct file *filp, char __user *buf,
1481					size_t count, loff_t *ppos)
1482{
1483	char *page;
1484	ssize_t length;
1485
1486	page = (char *)__get_free_page(GFP_KERNEL);
1487	if (!page)
1488		return -ENOMEM;
1489
1490	length = security_sidtab_hash_stats(page);
1491	if (length >= 0)
1492		length = simple_read_from_buffer(buf, count, ppos, page,
1493						length);
1494	free_page((unsigned long)page);
1495
1496	return length;
1497}
1498
1499static const struct file_operations sel_sidtab_hash_stats_ops = {
1500	.read		= sel_read_sidtab_hash_stats,
1501	.llseek		= generic_file_llseek,
1502};
1503
1504static const struct file_operations sel_avc_cache_threshold_ops = {
1505	.read		= sel_read_avc_cache_threshold,
1506	.write		= sel_write_avc_cache_threshold,
1507	.llseek		= generic_file_llseek,
1508};
1509
1510static const struct file_operations sel_avc_hash_stats_ops = {
1511	.read		= sel_read_avc_hash_stats,
1512	.llseek		= generic_file_llseek,
1513};
1514
1515#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1516static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1517{
1518	int cpu;
1519
1520	for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1521		if (!cpu_possible(cpu))
1522			continue;
1523		*idx = cpu + 1;
1524		return &per_cpu(avc_cache_stats, cpu);
1525	}
1526	(*idx)++;
1527	return NULL;
1528}
1529
1530static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1531{
1532	loff_t n = *pos - 1;
1533
1534	if (*pos == 0)
1535		return SEQ_START_TOKEN;
1536
1537	return sel_avc_get_stat_idx(&n);
1538}
1539
1540static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1541{
1542	return sel_avc_get_stat_idx(pos);
1543}
1544
1545static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1546{
1547	struct avc_cache_stats *st = v;
1548
1549	if (v == SEQ_START_TOKEN) {
1550		seq_puts(seq,
1551			 "lookups hits misses allocations reclaims frees\n");
1552	} else {
1553		unsigned int lookups = st->lookups;
1554		unsigned int misses = st->misses;
1555		unsigned int hits = lookups - misses;
1556		seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1557			   hits, misses, st->allocations,
1558			   st->reclaims, st->frees);
1559	}
1560	return 0;
1561}
1562
1563static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1564{ }
1565
1566static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1567	.start		= sel_avc_stats_seq_start,
1568	.next		= sel_avc_stats_seq_next,
1569	.show		= sel_avc_stats_seq_show,
1570	.stop		= sel_avc_stats_seq_stop,
1571};
1572
1573static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1574{
1575	return seq_open(file, &sel_avc_cache_stats_seq_ops);
1576}
1577
1578static const struct file_operations sel_avc_cache_stats_ops = {
1579	.open		= sel_open_avc_cache_stats,
1580	.read		= seq_read,
1581	.llseek		= seq_lseek,
1582	.release	= seq_release,
1583};
1584#endif
1585
1586static int sel_make_avc_files(struct dentry *dir)
1587{
1588	struct super_block *sb = dir->d_sb;
1589	struct selinux_fs_info *fsi = sb->s_fs_info;
1590	unsigned int i;
1591	static const struct tree_descr files[] = {
1592		{ "cache_threshold",
1593		  &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1594		{ "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1595#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1596		{ "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1597#endif
1598	};
1599
1600	for (i = 0; i < ARRAY_SIZE(files); i++) {
1601		struct inode *inode;
1602		struct dentry *dentry;
1603
1604		dentry = d_alloc_name(dir, files[i].name);
1605		if (!dentry)
1606			return -ENOMEM;
1607
1608		inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1609		if (!inode) {
1610			dput(dentry);
1611			return -ENOMEM;
1612		}
1613
1614		inode->i_fop = files[i].ops;
1615		inode->i_ino = ++fsi->last_ino;
1616		d_add(dentry, inode);
1617	}
1618
1619	return 0;
1620}
1621
1622static int sel_make_ss_files(struct dentry *dir)
1623{
1624	struct super_block *sb = dir->d_sb;
1625	struct selinux_fs_info *fsi = sb->s_fs_info;
1626	unsigned int i;
1627	static const struct tree_descr files[] = {
1628		{ "sidtab_hash_stats", &sel_sidtab_hash_stats_ops, S_IRUGO },
1629	};
1630
1631	for (i = 0; i < ARRAY_SIZE(files); i++) {
1632		struct inode *inode;
1633		struct dentry *dentry;
1634
1635		dentry = d_alloc_name(dir, files[i].name);
1636		if (!dentry)
1637			return -ENOMEM;
1638
1639		inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1640		if (!inode) {
1641			dput(dentry);
1642			return -ENOMEM;
1643		}
1644
1645		inode->i_fop = files[i].ops;
1646		inode->i_ino = ++fsi->last_ino;
1647		d_add(dentry, inode);
1648	}
1649
1650	return 0;
1651}
1652
1653static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1654				size_t count, loff_t *ppos)
1655{
1656	char *con;
1657	u32 sid, len;
1658	ssize_t ret;
1659
1660	sid = file_inode(file)->i_ino&SEL_INO_MASK;
1661	ret = security_sid_to_context(sid, &con, &len);
1662	if (ret)
1663		return ret;
1664
1665	ret = simple_read_from_buffer(buf, count, ppos, con, len);
1666	kfree(con);
1667	return ret;
1668}
1669
1670static const struct file_operations sel_initcon_ops = {
1671	.read		= sel_read_initcon,
1672	.llseek		= generic_file_llseek,
1673};
1674
1675static int sel_make_initcon_files(struct dentry *dir)
1676{
1677	unsigned int i;
1678
1679	for (i = 1; i <= SECINITSID_NUM; i++) {
1680		struct inode *inode;
1681		struct dentry *dentry;
1682		const char *s = security_get_initial_sid_context(i);
1683
1684		if (!s)
1685			continue;
1686		dentry = d_alloc_name(dir, s);
1687		if (!dentry)
1688			return -ENOMEM;
1689
1690		inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1691		if (!inode) {
1692			dput(dentry);
1693			return -ENOMEM;
1694		}
1695
1696		inode->i_fop = &sel_initcon_ops;
1697		inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1698		d_add(dentry, inode);
1699	}
1700
1701	return 0;
1702}
1703
1704static inline unsigned long sel_class_to_ino(u16 class)
1705{
1706	return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1707}
1708
1709static inline u16 sel_ino_to_class(unsigned long ino)
1710{
1711	return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1712}
1713
1714static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1715{
1716	return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1717}
1718
1719static inline u32 sel_ino_to_perm(unsigned long ino)
1720{
1721	return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1722}
1723
1724static ssize_t sel_read_class(struct file *file, char __user *buf,
1725				size_t count, loff_t *ppos)
1726{
1727	unsigned long ino = file_inode(file)->i_ino;
1728	char res[TMPBUFLEN];
1729	ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1730	return simple_read_from_buffer(buf, count, ppos, res, len);
1731}
1732
1733static const struct file_operations sel_class_ops = {
1734	.read		= sel_read_class,
1735	.llseek		= generic_file_llseek,
1736};
1737
1738static ssize_t sel_read_perm(struct file *file, char __user *buf,
1739				size_t count, loff_t *ppos)
1740{
1741	unsigned long ino = file_inode(file)->i_ino;
1742	char res[TMPBUFLEN];
1743	ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1744	return simple_read_from_buffer(buf, count, ppos, res, len);
1745}
1746
1747static const struct file_operations sel_perm_ops = {
1748	.read		= sel_read_perm,
1749	.llseek		= generic_file_llseek,
1750};
1751
1752static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1753				  size_t count, loff_t *ppos)
1754{
1755	int value;
1756	char tmpbuf[TMPBUFLEN];
1757	ssize_t length;
1758	unsigned long i_ino = file_inode(file)->i_ino;
1759
1760	value = security_policycap_supported(i_ino & SEL_INO_MASK);
1761	length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1762
1763	return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1764}
1765
1766static const struct file_operations sel_policycap_ops = {
1767	.read		= sel_read_policycap,
1768	.llseek		= generic_file_llseek,
1769};
1770
1771static int sel_make_perm_files(struct selinux_policy *newpolicy,
1772			char *objclass, int classvalue,
1773			struct dentry *dir)
1774{
1775	u32 i, nperms;
1776	int rc;
1777	char **perms;
1778
1779	rc = security_get_permissions(newpolicy, objclass, &perms, &nperms);
1780	if (rc)
1781		return rc;
1782
1783	for (i = 0; i < nperms; i++) {
1784		struct inode *inode;
1785		struct dentry *dentry;
1786
1787		rc = -ENOMEM;
1788		dentry = d_alloc_name(dir, perms[i]);
1789		if (!dentry)
1790			goto out;
1791
1792		rc = -ENOMEM;
1793		inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1794		if (!inode) {
1795			dput(dentry);
1796			goto out;
1797		}
1798
1799		inode->i_fop = &sel_perm_ops;
1800		/* i+1 since perm values are 1-indexed */
1801		inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1802		d_add(dentry, inode);
1803	}
1804	rc = 0;
1805out:
1806	for (i = 0; i < nperms; i++)
1807		kfree(perms[i]);
1808	kfree(perms);
1809	return rc;
1810}
1811
1812static int sel_make_class_dir_entries(struct selinux_policy *newpolicy,
1813				char *classname, int index,
1814				struct dentry *dir)
1815{
1816	struct super_block *sb = dir->d_sb;
1817	struct selinux_fs_info *fsi = sb->s_fs_info;
1818	struct dentry *dentry = NULL;
1819	struct inode *inode = NULL;
 
1820
1821	dentry = d_alloc_name(dir, "index");
1822	if (!dentry)
1823		return -ENOMEM;
1824
1825	inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1826	if (!inode) {
1827		dput(dentry);
1828		return -ENOMEM;
1829	}
1830
1831	inode->i_fop = &sel_class_ops;
1832	inode->i_ino = sel_class_to_ino(index);
1833	d_add(dentry, inode);
1834
1835	dentry = sel_make_dir(dir, "perms", &fsi->last_class_ino);
1836	if (IS_ERR(dentry))
1837		return PTR_ERR(dentry);
1838
1839	return sel_make_perm_files(newpolicy, classname, index, dentry);
 
 
1840}
1841
1842static int sel_make_classes(struct selinux_policy *newpolicy,
1843			    struct dentry *class_dir,
1844			    unsigned long *last_class_ino)
1845{
1846	u32 i, nclasses;
1847	int rc;
1848	char **classes;
1849
1850	rc = security_get_classes(newpolicy, &classes, &nclasses);
 
 
 
1851	if (rc)
1852		return rc;
1853
1854	/* +2 since classes are 1-indexed */
1855	*last_class_ino = sel_class_to_ino(nclasses + 2);
1856
1857	for (i = 0; i < nclasses; i++) {
1858		struct dentry *class_name_dir;
1859
1860		class_name_dir = sel_make_dir(class_dir, classes[i],
1861					      last_class_ino);
1862		if (IS_ERR(class_name_dir)) {
1863			rc = PTR_ERR(class_name_dir);
1864			goto out;
1865		}
1866
1867		/* i+1 since class values are 1-indexed */
1868		rc = sel_make_class_dir_entries(newpolicy, classes[i], i + 1,
1869				class_name_dir);
1870		if (rc)
1871			goto out;
1872	}
1873	rc = 0;
1874out:
1875	for (i = 0; i < nclasses; i++)
1876		kfree(classes[i]);
1877	kfree(classes);
1878	return rc;
1879}
1880
1881static int sel_make_policycap(struct selinux_fs_info *fsi)
1882{
1883	unsigned int iter;
1884	struct dentry *dentry = NULL;
1885	struct inode *inode = NULL;
1886
1887	for (iter = 0; iter <= POLICYDB_CAP_MAX; iter++) {
1888		if (iter < ARRAY_SIZE(selinux_policycap_names))
1889			dentry = d_alloc_name(fsi->policycap_dir,
1890					      selinux_policycap_names[iter]);
 
 
1891		else
1892			dentry = d_alloc_name(fsi->policycap_dir, "unknown");
1893
1894		if (dentry == NULL)
1895			return -ENOMEM;
1896
1897		inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
1898		if (inode == NULL) {
1899			dput(dentry);
1900			return -ENOMEM;
1901		}
1902
1903		inode->i_fop = &sel_policycap_ops;
1904		inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
1905		d_add(dentry, inode);
1906	}
1907
1908	return 0;
1909}
1910
1911static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
1912			unsigned long *ino)
1913{
1914	struct dentry *dentry = d_alloc_name(dir, name);
1915	struct inode *inode;
1916
1917	if (!dentry)
1918		return ERR_PTR(-ENOMEM);
1919
1920	inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
1921	if (!inode) {
1922		dput(dentry);
1923		return ERR_PTR(-ENOMEM);
1924	}
1925
1926	inode->i_op = &simple_dir_inode_operations;
1927	inode->i_fop = &simple_dir_operations;
1928	inode->i_ino = ++(*ino);
1929	/* directory inodes start off with i_nlink == 2 (for "." entry) */
1930	inc_nlink(inode);
1931	d_add(dentry, inode);
1932	/* bump link count on parent directory, too */
1933	inc_nlink(d_inode(dir));
1934
1935	return dentry;
1936}
1937
1938static int reject_all(struct mnt_idmap *idmap, struct inode *inode, int mask)
1939{
1940	return -EPERM;	// no access for anyone, root or no root.
1941}
1942
1943static const struct inode_operations swapover_dir_inode_operations = {
1944	.lookup		= simple_lookup,
1945	.permission	= reject_all,
1946};
1947
1948static struct dentry *sel_make_swapover_dir(struct super_block *sb,
1949						unsigned long *ino)
1950{
1951	struct dentry *dentry = d_alloc_name(sb->s_root, ".swapover");
1952	struct inode *inode;
1953
1954	if (!dentry)
1955		return ERR_PTR(-ENOMEM);
1956
1957	inode = sel_make_inode(sb, S_IFDIR);
1958	if (!inode) {
1959		dput(dentry);
1960		return ERR_PTR(-ENOMEM);
1961	}
1962
1963	inode->i_op = &swapover_dir_inode_operations;
1964	inode->i_ino = ++(*ino);
1965	/* directory inodes start off with i_nlink == 2 (for "." entry) */
1966	inc_nlink(inode);
1967	inode_lock(sb->s_root->d_inode);
1968	d_add(dentry, inode);
1969	inc_nlink(sb->s_root->d_inode);
1970	inode_unlock(sb->s_root->d_inode);
1971	return dentry;
1972}
1973
1974#define NULL_FILE_NAME "null"
1975
1976static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
1977{
1978	struct selinux_fs_info *fsi;
1979	int ret;
1980	struct dentry *dentry;
1981	struct inode *inode;
1982	struct inode_security_struct *isec;
1983
1984	static const struct tree_descr selinux_files[] = {
1985		[SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
1986		[SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
1987		[SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
1988		[SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
1989		[SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
1990		[SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
1991		[SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
1992		[SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
1993		[SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
1994		[SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
1995		[SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
1996		[SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
1997		[SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
1998		[SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
1999		[SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
2000		[SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
2001		[SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
2002		[SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
2003					S_IWUGO},
2004		/* last one */ {""}
2005	};
2006
2007	ret = selinux_fs_info_create(sb);
2008	if (ret)
2009		goto err;
2010
2011	ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
2012	if (ret)
2013		goto err;
2014
2015	fsi = sb->s_fs_info;
2016	fsi->bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &fsi->last_ino);
2017	if (IS_ERR(fsi->bool_dir)) {
2018		ret = PTR_ERR(fsi->bool_dir);
2019		fsi->bool_dir = NULL;
2020		goto err;
2021	}
2022
2023	ret = -ENOMEM;
2024	dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
2025	if (!dentry)
2026		goto err;
2027
2028	ret = -ENOMEM;
2029	inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
2030	if (!inode) {
2031		dput(dentry);
2032		goto err;
2033	}
2034
2035	inode->i_ino = ++fsi->last_ino;
2036	isec = selinux_inode(inode);
2037	isec->sid = SECINITSID_DEVNULL;
2038	isec->sclass = SECCLASS_CHR_FILE;
2039	isec->initialized = LABEL_INITIALIZED;
2040
2041	init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
2042	d_add(dentry, inode);
 
2043
2044	dentry = sel_make_dir(sb->s_root, "avc", &fsi->last_ino);
2045	if (IS_ERR(dentry)) {
2046		ret = PTR_ERR(dentry);
2047		goto err;
2048	}
2049
2050	ret = sel_make_avc_files(dentry);
2051	if (ret)
2052		goto err;
2053
2054	dentry = sel_make_dir(sb->s_root, "ss", &fsi->last_ino);
2055	if (IS_ERR(dentry)) {
2056		ret = PTR_ERR(dentry);
2057		goto err;
2058	}
2059
2060	ret = sel_make_ss_files(dentry);
2061	if (ret)
2062		goto err;
2063
2064	dentry = sel_make_dir(sb->s_root, "initial_contexts", &fsi->last_ino);
2065	if (IS_ERR(dentry)) {
2066		ret = PTR_ERR(dentry);
2067		goto err;
2068	}
2069
2070	ret = sel_make_initcon_files(dentry);
2071	if (ret)
2072		goto err;
2073
2074	fsi->class_dir = sel_make_dir(sb->s_root, CLASS_DIR_NAME, &fsi->last_ino);
2075	if (IS_ERR(fsi->class_dir)) {
2076		ret = PTR_ERR(fsi->class_dir);
2077		fsi->class_dir = NULL;
2078		goto err;
2079	}
2080
2081	fsi->policycap_dir = sel_make_dir(sb->s_root, POLICYCAP_DIR_NAME,
2082					  &fsi->last_ino);
2083	if (IS_ERR(fsi->policycap_dir)) {
2084		ret = PTR_ERR(fsi->policycap_dir);
2085		fsi->policycap_dir = NULL;
2086		goto err;
2087	}
2088
2089	ret = sel_make_policycap(fsi);
2090	if (ret) {
2091		pr_err("SELinux: failed to load policy capabilities\n");
2092		goto err;
2093	}
2094
2095	return 0;
2096err:
2097	pr_err("SELinux: %s:  failed while creating inodes\n",
2098		__func__);
2099
2100	selinux_fs_info_free(sb);
2101
2102	return ret;
2103}
2104
2105static int sel_get_tree(struct fs_context *fc)
2106{
2107	return get_tree_single(fc, sel_fill_super);
2108}
2109
2110static const struct fs_context_operations sel_context_ops = {
2111	.get_tree	= sel_get_tree,
2112};
2113
2114static int sel_init_fs_context(struct fs_context *fc)
2115{
2116	fc->ops = &sel_context_ops;
2117	return 0;
2118}
2119
2120static void sel_kill_sb(struct super_block *sb)
2121{
2122	selinux_fs_info_free(sb);
2123	kill_litter_super(sb);
2124}
2125
2126static struct file_system_type sel_fs_type = {
2127	.name		= "selinuxfs",
2128	.init_fs_context = sel_init_fs_context,
2129	.kill_sb	= sel_kill_sb,
2130};
2131
2132struct path selinux_null __ro_after_init;
2133
2134static int __init init_sel_fs(void)
2135{
2136	struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
2137					  sizeof(NULL_FILE_NAME)-1);
2138	int err;
2139
2140	if (!selinux_enabled_boot)
2141		return 0;
2142
2143	err = sysfs_create_mount_point(fs_kobj, "selinux");
2144	if (err)
2145		return err;
2146
2147	err = register_filesystem(&sel_fs_type);
2148	if (err) {
2149		sysfs_remove_mount_point(fs_kobj, "selinux");
2150		return err;
2151	}
2152
2153	selinux_null.mnt = kern_mount(&sel_fs_type);
2154	if (IS_ERR(selinux_null.mnt)) {
2155		pr_err("selinuxfs:  could not mount!\n");
2156		err = PTR_ERR(selinux_null.mnt);
2157		selinux_null.mnt = NULL;
2158		return err;
2159	}
2160
2161	selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
2162						&null_name);
2163	if (IS_ERR(selinux_null.dentry)) {
2164		pr_err("selinuxfs:  could not lookup null!\n");
2165		err = PTR_ERR(selinux_null.dentry);
2166		selinux_null.dentry = NULL;
2167		return err;
2168	}
2169
2170	/*
2171	 * Try to pre-allocate the status page, so the sequence number of the
2172	 * initial policy load can be stored.
2173	 */
2174	(void) selinux_kernel_status_page();
2175
2176	return err;
2177}
2178
2179__initcall(init_sel_fs);