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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;
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 __lsm_ro_after_init = 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 = 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 return 1;
148}
149__setup("checkreqprot=", checkreqprot_setup);
150
151/**
152 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
153 *
154 * Description:
155 * This function checks the SECMARK reference counter to see if any SECMARK
156 * targets are currently configured, if the reference counter is greater than
157 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
158 * enabled, false (0) if SECMARK is disabled. If the always_check_network
159 * policy capability is enabled, SECMARK is always considered enabled.
160 *
161 */
162static int selinux_secmark_enabled(void)
163{
164 return (selinux_policycap_alwaysnetwork() ||
165 atomic_read(&selinux_secmark_refcount));
166}
167
168/**
169 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
170 *
171 * Description:
172 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
173 * (1) if any are enabled or false (0) if neither are enabled. If the
174 * always_check_network policy capability is enabled, peer labeling
175 * is always considered enabled.
176 *
177 */
178static int selinux_peerlbl_enabled(void)
179{
180 return (selinux_policycap_alwaysnetwork() ||
181 netlbl_enabled() || selinux_xfrm_enabled());
182}
183
184static int selinux_netcache_avc_callback(u32 event)
185{
186 if (event == AVC_CALLBACK_RESET) {
187 sel_netif_flush();
188 sel_netnode_flush();
189 sel_netport_flush();
190 synchronize_net();
191 }
192 return 0;
193}
194
195static int selinux_lsm_notifier_avc_callback(u32 event)
196{
197 if (event == AVC_CALLBACK_RESET) {
198 sel_ib_pkey_flush();
199 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
200 }
201
202 return 0;
203}
204
205/*
206 * initialise the security for the init task
207 */
208static void cred_init_security(void)
209{
210 struct cred *cred = (struct cred *) current->real_cred;
211 struct task_security_struct *tsec;
212
213 tsec = selinux_cred(cred);
214 tsec->osid = tsec->sid = SECINITSID_KERNEL;
215}
216
217/*
218 * get the security ID of a set of credentials
219 */
220static inline u32 cred_sid(const struct cred *cred)
221{
222 const struct task_security_struct *tsec;
223
224 tsec = selinux_cred(cred);
225 return tsec->sid;
226}
227
228/*
229 * get the objective security ID of a task
230 */
231static inline u32 task_sid(const struct task_struct *task)
232{
233 u32 sid;
234
235 rcu_read_lock();
236 sid = cred_sid(__task_cred(task));
237 rcu_read_unlock();
238 return sid;
239}
240
241/* Allocate and free functions for each kind of security blob. */
242
243static int inode_alloc_security(struct inode *inode)
244{
245 struct inode_security_struct *isec = selinux_inode(inode);
246 u32 sid = current_sid();
247
248 spin_lock_init(&isec->lock);
249 INIT_LIST_HEAD(&isec->list);
250 isec->inode = inode;
251 isec->sid = SECINITSID_UNLABELED;
252 isec->sclass = SECCLASS_FILE;
253 isec->task_sid = sid;
254 isec->initialized = LABEL_INVALID;
255
256 return 0;
257}
258
259static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
260
261/*
262 * Try reloading inode security labels that have been marked as invalid. The
263 * @may_sleep parameter indicates when sleeping and thus reloading labels is
264 * allowed; when set to false, returns -ECHILD when the label is
265 * invalid. The @dentry parameter should be set to a dentry of the inode.
266 */
267static int __inode_security_revalidate(struct inode *inode,
268 struct dentry *dentry,
269 bool may_sleep)
270{
271 struct inode_security_struct *isec = selinux_inode(inode);
272
273 might_sleep_if(may_sleep);
274
275 if (selinux_state.initialized &&
276 isec->initialized != LABEL_INITIALIZED) {
277 if (!may_sleep)
278 return -ECHILD;
279
280 /*
281 * Try reloading the inode security label. This will fail if
282 * @opt_dentry is NULL and no dentry for this inode can be
283 * found; in that case, continue using the old label.
284 */
285 inode_doinit_with_dentry(inode, dentry);
286 }
287 return 0;
288}
289
290static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
291{
292 return selinux_inode(inode);
293}
294
295static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
296{
297 int error;
298
299 error = __inode_security_revalidate(inode, NULL, !rcu);
300 if (error)
301 return ERR_PTR(error);
302 return selinux_inode(inode);
303}
304
305/*
306 * Get the security label of an inode.
307 */
308static struct inode_security_struct *inode_security(struct inode *inode)
309{
310 __inode_security_revalidate(inode, NULL, true);
311 return selinux_inode(inode);
312}
313
314static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
315{
316 struct inode *inode = d_backing_inode(dentry);
317
318 return selinux_inode(inode);
319}
320
321/*
322 * Get the security label of a dentry's backing inode.
323 */
324static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
325{
326 struct inode *inode = d_backing_inode(dentry);
327
328 __inode_security_revalidate(inode, dentry, true);
329 return selinux_inode(inode);
330}
331
332static void inode_free_security(struct inode *inode)
333{
334 struct inode_security_struct *isec = selinux_inode(inode);
335 struct superblock_security_struct *sbsec;
336
337 if (!isec)
338 return;
339 sbsec = inode->i_sb->s_security;
340 /*
341 * As not all inode security structures are in a list, we check for
342 * empty list outside of the lock to make sure that we won't waste
343 * time taking a lock doing nothing.
344 *
345 * The list_del_init() function can be safely called more than once.
346 * It should not be possible for this function to be called with
347 * concurrent list_add(), but for better safety against future changes
348 * in the code, we use list_empty_careful() here.
349 */
350 if (!list_empty_careful(&isec->list)) {
351 spin_lock(&sbsec->isec_lock);
352 list_del_init(&isec->list);
353 spin_unlock(&sbsec->isec_lock);
354 }
355}
356
357static int file_alloc_security(struct file *file)
358{
359 struct file_security_struct *fsec = selinux_file(file);
360 u32 sid = current_sid();
361
362 fsec->sid = sid;
363 fsec->fown_sid = sid;
364
365 return 0;
366}
367
368static int superblock_alloc_security(struct super_block *sb)
369{
370 struct superblock_security_struct *sbsec;
371
372 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
373 if (!sbsec)
374 return -ENOMEM;
375
376 mutex_init(&sbsec->lock);
377 INIT_LIST_HEAD(&sbsec->isec_head);
378 spin_lock_init(&sbsec->isec_lock);
379 sbsec->sb = sb;
380 sbsec->sid = SECINITSID_UNLABELED;
381 sbsec->def_sid = SECINITSID_FILE;
382 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
383 sb->s_security = sbsec;
384
385 return 0;
386}
387
388static void superblock_free_security(struct super_block *sb)
389{
390 struct superblock_security_struct *sbsec = sb->s_security;
391 sb->s_security = NULL;
392 kfree(sbsec);
393}
394
395struct selinux_mnt_opts {
396 const char *fscontext, *context, *rootcontext, *defcontext;
397};
398
399static void selinux_free_mnt_opts(void *mnt_opts)
400{
401 struct selinux_mnt_opts *opts = mnt_opts;
402 kfree(opts->fscontext);
403 kfree(opts->context);
404 kfree(opts->rootcontext);
405 kfree(opts->defcontext);
406 kfree(opts);
407}
408
409static inline int inode_doinit(struct inode *inode)
410{
411 return inode_doinit_with_dentry(inode, NULL);
412}
413
414enum {
415 Opt_error = -1,
416 Opt_context = 0,
417 Opt_defcontext = 1,
418 Opt_fscontext = 2,
419 Opt_rootcontext = 3,
420 Opt_seclabel = 4,
421};
422
423#define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
424static struct {
425 const char *name;
426 int len;
427 int opt;
428 bool has_arg;
429} tokens[] = {
430 A(context, true),
431 A(fscontext, true),
432 A(defcontext, true),
433 A(rootcontext, true),
434 A(seclabel, false),
435};
436#undef A
437
438static int match_opt_prefix(char *s, int l, char **arg)
439{
440 int i;
441
442 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
443 size_t len = tokens[i].len;
444 if (len > l || memcmp(s, tokens[i].name, len))
445 continue;
446 if (tokens[i].has_arg) {
447 if (len == l || s[len] != '=')
448 continue;
449 *arg = s + len + 1;
450 } else if (len != l)
451 continue;
452 return tokens[i].opt;
453 }
454 return Opt_error;
455}
456
457#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
458
459static int may_context_mount_sb_relabel(u32 sid,
460 struct superblock_security_struct *sbsec,
461 const struct cred *cred)
462{
463 const struct task_security_struct *tsec = selinux_cred(cred);
464 int rc;
465
466 rc = avc_has_perm(&selinux_state,
467 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
468 FILESYSTEM__RELABELFROM, NULL);
469 if (rc)
470 return rc;
471
472 rc = avc_has_perm(&selinux_state,
473 tsec->sid, sid, SECCLASS_FILESYSTEM,
474 FILESYSTEM__RELABELTO, NULL);
475 return rc;
476}
477
478static int may_context_mount_inode_relabel(u32 sid,
479 struct superblock_security_struct *sbsec,
480 const struct cred *cred)
481{
482 const struct task_security_struct *tsec = selinux_cred(cred);
483 int rc;
484 rc = avc_has_perm(&selinux_state,
485 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
486 FILESYSTEM__RELABELFROM, NULL);
487 if (rc)
488 return rc;
489
490 rc = avc_has_perm(&selinux_state,
491 sid, sbsec->sid, SECCLASS_FILESYSTEM,
492 FILESYSTEM__ASSOCIATE, NULL);
493 return rc;
494}
495
496static int selinux_is_genfs_special_handling(struct super_block *sb)
497{
498 /* Special handling. Genfs but also in-core setxattr handler */
499 return !strcmp(sb->s_type->name, "sysfs") ||
500 !strcmp(sb->s_type->name, "pstore") ||
501 !strcmp(sb->s_type->name, "debugfs") ||
502 !strcmp(sb->s_type->name, "tracefs") ||
503 !strcmp(sb->s_type->name, "rootfs") ||
504 (selinux_policycap_cgroupseclabel() &&
505 (!strcmp(sb->s_type->name, "cgroup") ||
506 !strcmp(sb->s_type->name, "cgroup2")));
507}
508
509static int selinux_is_sblabel_mnt(struct super_block *sb)
510{
511 struct superblock_security_struct *sbsec = sb->s_security;
512
513 /*
514 * IMPORTANT: Double-check logic in this function when adding a new
515 * SECURITY_FS_USE_* definition!
516 */
517 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
518
519 switch (sbsec->behavior) {
520 case SECURITY_FS_USE_XATTR:
521 case SECURITY_FS_USE_TRANS:
522 case SECURITY_FS_USE_TASK:
523 case SECURITY_FS_USE_NATIVE:
524 return 1;
525
526 case SECURITY_FS_USE_GENFS:
527 return selinux_is_genfs_special_handling(sb);
528
529 /* Never allow relabeling on context mounts */
530 case SECURITY_FS_USE_MNTPOINT:
531 case SECURITY_FS_USE_NONE:
532 default:
533 return 0;
534 }
535}
536
537static int sb_finish_set_opts(struct super_block *sb)
538{
539 struct superblock_security_struct *sbsec = sb->s_security;
540 struct dentry *root = sb->s_root;
541 struct inode *root_inode = d_backing_inode(root);
542 int rc = 0;
543
544 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
545 /* Make sure that the xattr handler exists and that no
546 error other than -ENODATA is returned by getxattr on
547 the root directory. -ENODATA is ok, as this may be
548 the first boot of the SELinux kernel before we have
549 assigned xattr values to the filesystem. */
550 if (!(root_inode->i_opflags & IOP_XATTR)) {
551 pr_warn("SELinux: (dev %s, type %s) has no "
552 "xattr support\n", sb->s_id, sb->s_type->name);
553 rc = -EOPNOTSUPP;
554 goto out;
555 }
556
557 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
558 if (rc < 0 && rc != -ENODATA) {
559 if (rc == -EOPNOTSUPP)
560 pr_warn("SELinux: (dev %s, type "
561 "%s) has no security xattr handler\n",
562 sb->s_id, sb->s_type->name);
563 else
564 pr_warn("SELinux: (dev %s, type "
565 "%s) getxattr errno %d\n", sb->s_id,
566 sb->s_type->name, -rc);
567 goto out;
568 }
569 }
570
571 sbsec->flags |= SE_SBINITIALIZED;
572
573 /*
574 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply
575 * leave the flag untouched because sb_clone_mnt_opts might be handing
576 * us a superblock that needs the flag to be cleared.
577 */
578 if (selinux_is_sblabel_mnt(sb))
579 sbsec->flags |= SBLABEL_MNT;
580 else
581 sbsec->flags &= ~SBLABEL_MNT;
582
583 /* Initialize the root inode. */
584 rc = inode_doinit_with_dentry(root_inode, root);
585
586 /* Initialize any other inodes associated with the superblock, e.g.
587 inodes created prior to initial policy load or inodes created
588 during get_sb by a pseudo filesystem that directly
589 populates itself. */
590 spin_lock(&sbsec->isec_lock);
591 while (!list_empty(&sbsec->isec_head)) {
592 struct inode_security_struct *isec =
593 list_first_entry(&sbsec->isec_head,
594 struct inode_security_struct, list);
595 struct inode *inode = isec->inode;
596 list_del_init(&isec->list);
597 spin_unlock(&sbsec->isec_lock);
598 inode = igrab(inode);
599 if (inode) {
600 if (!IS_PRIVATE(inode))
601 inode_doinit(inode);
602 iput(inode);
603 }
604 spin_lock(&sbsec->isec_lock);
605 }
606 spin_unlock(&sbsec->isec_lock);
607out:
608 return rc;
609}
610
611static int bad_option(struct superblock_security_struct *sbsec, char flag,
612 u32 old_sid, u32 new_sid)
613{
614 char mnt_flags = sbsec->flags & SE_MNTMASK;
615
616 /* check if the old mount command had the same options */
617 if (sbsec->flags & SE_SBINITIALIZED)
618 if (!(sbsec->flags & flag) ||
619 (old_sid != new_sid))
620 return 1;
621
622 /* check if we were passed the same options twice,
623 * aka someone passed context=a,context=b
624 */
625 if (!(sbsec->flags & SE_SBINITIALIZED))
626 if (mnt_flags & flag)
627 return 1;
628 return 0;
629}
630
631static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
632{
633 int rc = security_context_str_to_sid(&selinux_state, s,
634 sid, GFP_KERNEL);
635 if (rc)
636 pr_warn("SELinux: security_context_str_to_sid"
637 "(%s) failed for (dev %s, type %s) errno=%d\n",
638 s, sb->s_id, sb->s_type->name, rc);
639 return rc;
640}
641
642/*
643 * Allow filesystems with binary mount data to explicitly set mount point
644 * labeling information.
645 */
646static int selinux_set_mnt_opts(struct super_block *sb,
647 void *mnt_opts,
648 unsigned long kern_flags,
649 unsigned long *set_kern_flags)
650{
651 const struct cred *cred = current_cred();
652 struct superblock_security_struct *sbsec = sb->s_security;
653 struct dentry *root = sbsec->sb->s_root;
654 struct selinux_mnt_opts *opts = mnt_opts;
655 struct inode_security_struct *root_isec;
656 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
657 u32 defcontext_sid = 0;
658 int rc = 0;
659
660 mutex_lock(&sbsec->lock);
661
662 if (!selinux_state.initialized) {
663 if (!opts) {
664 /* Defer initialization until selinux_complete_init,
665 after the initial policy is loaded and the security
666 server is ready to handle calls. */
667 goto out;
668 }
669 rc = -EINVAL;
670 pr_warn("SELinux: Unable to set superblock options "
671 "before the security server is initialized\n");
672 goto out;
673 }
674 if (kern_flags && !set_kern_flags) {
675 /* Specifying internal flags without providing a place to
676 * place the results is not allowed */
677 rc = -EINVAL;
678 goto out;
679 }
680
681 /*
682 * Binary mount data FS will come through this function twice. Once
683 * from an explicit call and once from the generic calls from the vfs.
684 * Since the generic VFS calls will not contain any security mount data
685 * we need to skip the double mount verification.
686 *
687 * This does open a hole in which we will not notice if the first
688 * mount using this sb set explict options and a second mount using
689 * this sb does not set any security options. (The first options
690 * will be used for both mounts)
691 */
692 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
693 && !opts)
694 goto out;
695
696 root_isec = backing_inode_security_novalidate(root);
697
698 /*
699 * parse the mount options, check if they are valid sids.
700 * also check if someone is trying to mount the same sb more
701 * than once with different security options.
702 */
703 if (opts) {
704 if (opts->fscontext) {
705 rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
706 if (rc)
707 goto out;
708 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
709 fscontext_sid))
710 goto out_double_mount;
711 sbsec->flags |= FSCONTEXT_MNT;
712 }
713 if (opts->context) {
714 rc = parse_sid(sb, opts->context, &context_sid);
715 if (rc)
716 goto out;
717 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
718 context_sid))
719 goto out_double_mount;
720 sbsec->flags |= CONTEXT_MNT;
721 }
722 if (opts->rootcontext) {
723 rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
724 if (rc)
725 goto out;
726 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
727 rootcontext_sid))
728 goto out_double_mount;
729 sbsec->flags |= ROOTCONTEXT_MNT;
730 }
731 if (opts->defcontext) {
732 rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
733 if (rc)
734 goto out;
735 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
736 defcontext_sid))
737 goto out_double_mount;
738 sbsec->flags |= DEFCONTEXT_MNT;
739 }
740 }
741
742 if (sbsec->flags & SE_SBINITIALIZED) {
743 /* previously mounted with options, but not on this attempt? */
744 if ((sbsec->flags & SE_MNTMASK) && !opts)
745 goto out_double_mount;
746 rc = 0;
747 goto out;
748 }
749
750 if (strcmp(sb->s_type->name, "proc") == 0)
751 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
752
753 if (!strcmp(sb->s_type->name, "debugfs") ||
754 !strcmp(sb->s_type->name, "tracefs") ||
755 !strcmp(sb->s_type->name, "pstore"))
756 sbsec->flags |= SE_SBGENFS;
757
758 if (!strcmp(sb->s_type->name, "sysfs") ||
759 !strcmp(sb->s_type->name, "cgroup") ||
760 !strcmp(sb->s_type->name, "cgroup2"))
761 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
762
763 if (!sbsec->behavior) {
764 /*
765 * Determine the labeling behavior to use for this
766 * filesystem type.
767 */
768 rc = security_fs_use(&selinux_state, sb);
769 if (rc) {
770 pr_warn("%s: security_fs_use(%s) returned %d\n",
771 __func__, sb->s_type->name, rc);
772 goto out;
773 }
774 }
775
776 /*
777 * If this is a user namespace mount and the filesystem type is not
778 * explicitly whitelisted, then no contexts are allowed on the command
779 * line and security labels must be ignored.
780 */
781 if (sb->s_user_ns != &init_user_ns &&
782 strcmp(sb->s_type->name, "tmpfs") &&
783 strcmp(sb->s_type->name, "ramfs") &&
784 strcmp(sb->s_type->name, "devpts")) {
785 if (context_sid || fscontext_sid || rootcontext_sid ||
786 defcontext_sid) {
787 rc = -EACCES;
788 goto out;
789 }
790 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
791 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
792 rc = security_transition_sid(&selinux_state,
793 current_sid(),
794 current_sid(),
795 SECCLASS_FILE, NULL,
796 &sbsec->mntpoint_sid);
797 if (rc)
798 goto out;
799 }
800 goto out_set_opts;
801 }
802
803 /* sets the context of the superblock for the fs being mounted. */
804 if (fscontext_sid) {
805 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
806 if (rc)
807 goto out;
808
809 sbsec->sid = fscontext_sid;
810 }
811
812 /*
813 * Switch to using mount point labeling behavior.
814 * sets the label used on all file below the mountpoint, and will set
815 * the superblock context if not already set.
816 */
817 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
818 sbsec->behavior = SECURITY_FS_USE_NATIVE;
819 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
820 }
821
822 if (context_sid) {
823 if (!fscontext_sid) {
824 rc = may_context_mount_sb_relabel(context_sid, sbsec,
825 cred);
826 if (rc)
827 goto out;
828 sbsec->sid = context_sid;
829 } else {
830 rc = may_context_mount_inode_relabel(context_sid, sbsec,
831 cred);
832 if (rc)
833 goto out;
834 }
835 if (!rootcontext_sid)
836 rootcontext_sid = context_sid;
837
838 sbsec->mntpoint_sid = context_sid;
839 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
840 }
841
842 if (rootcontext_sid) {
843 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
844 cred);
845 if (rc)
846 goto out;
847
848 root_isec->sid = rootcontext_sid;
849 root_isec->initialized = LABEL_INITIALIZED;
850 }
851
852 if (defcontext_sid) {
853 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
854 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
855 rc = -EINVAL;
856 pr_warn("SELinux: defcontext option is "
857 "invalid for this filesystem type\n");
858 goto out;
859 }
860
861 if (defcontext_sid != sbsec->def_sid) {
862 rc = may_context_mount_inode_relabel(defcontext_sid,
863 sbsec, cred);
864 if (rc)
865 goto out;
866 }
867
868 sbsec->def_sid = defcontext_sid;
869 }
870
871out_set_opts:
872 rc = sb_finish_set_opts(sb);
873out:
874 mutex_unlock(&sbsec->lock);
875 return rc;
876out_double_mount:
877 rc = -EINVAL;
878 pr_warn("SELinux: mount invalid. Same superblock, different "
879 "security settings for (dev %s, type %s)\n", sb->s_id,
880 sb->s_type->name);
881 goto out;
882}
883
884static int selinux_cmp_sb_context(const struct super_block *oldsb,
885 const struct super_block *newsb)
886{
887 struct superblock_security_struct *old = oldsb->s_security;
888 struct superblock_security_struct *new = newsb->s_security;
889 char oldflags = old->flags & SE_MNTMASK;
890 char newflags = new->flags & SE_MNTMASK;
891
892 if (oldflags != newflags)
893 goto mismatch;
894 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
895 goto mismatch;
896 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
897 goto mismatch;
898 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
899 goto mismatch;
900 if (oldflags & ROOTCONTEXT_MNT) {
901 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
902 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
903 if (oldroot->sid != newroot->sid)
904 goto mismatch;
905 }
906 return 0;
907mismatch:
908 pr_warn("SELinux: mount invalid. Same superblock, "
909 "different security settings for (dev %s, "
910 "type %s)\n", newsb->s_id, newsb->s_type->name);
911 return -EBUSY;
912}
913
914static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
915 struct super_block *newsb,
916 unsigned long kern_flags,
917 unsigned long *set_kern_flags)
918{
919 int rc = 0;
920 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
921 struct superblock_security_struct *newsbsec = newsb->s_security;
922
923 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
924 int set_context = (oldsbsec->flags & CONTEXT_MNT);
925 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
926
927 /*
928 * if the parent was able to be mounted it clearly had no special lsm
929 * mount options. thus we can safely deal with this superblock later
930 */
931 if (!selinux_state.initialized)
932 return 0;
933
934 /*
935 * Specifying internal flags without providing a place to
936 * place the results is not allowed.
937 */
938 if (kern_flags && !set_kern_flags)
939 return -EINVAL;
940
941 /* how can we clone if the old one wasn't set up?? */
942 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
943
944 /* if fs is reusing a sb, make sure that the contexts match */
945 if (newsbsec->flags & SE_SBINITIALIZED) {
946 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
947 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
948 return selinux_cmp_sb_context(oldsb, newsb);
949 }
950
951 mutex_lock(&newsbsec->lock);
952
953 newsbsec->flags = oldsbsec->flags;
954
955 newsbsec->sid = oldsbsec->sid;
956 newsbsec->def_sid = oldsbsec->def_sid;
957 newsbsec->behavior = oldsbsec->behavior;
958
959 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
960 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
961 rc = security_fs_use(&selinux_state, newsb);
962 if (rc)
963 goto out;
964 }
965
966 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
967 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
968 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
969 }
970
971 if (set_context) {
972 u32 sid = oldsbsec->mntpoint_sid;
973
974 if (!set_fscontext)
975 newsbsec->sid = sid;
976 if (!set_rootcontext) {
977 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
978 newisec->sid = sid;
979 }
980 newsbsec->mntpoint_sid = sid;
981 }
982 if (set_rootcontext) {
983 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
984 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
985
986 newisec->sid = oldisec->sid;
987 }
988
989 sb_finish_set_opts(newsb);
990out:
991 mutex_unlock(&newsbsec->lock);
992 return rc;
993}
994
995static int selinux_add_opt(int token, const char *s, void **mnt_opts)
996{
997 struct selinux_mnt_opts *opts = *mnt_opts;
998
999 if (token == Opt_seclabel) /* eaten and completely ignored */
1000 return 0;
1001
1002 if (!opts) {
1003 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
1004 if (!opts)
1005 return -ENOMEM;
1006 *mnt_opts = opts;
1007 }
1008 if (!s)
1009 return -ENOMEM;
1010 switch (token) {
1011 case Opt_context:
1012 if (opts->context || opts->defcontext)
1013 goto Einval;
1014 opts->context = s;
1015 break;
1016 case Opt_fscontext:
1017 if (opts->fscontext)
1018 goto Einval;
1019 opts->fscontext = s;
1020 break;
1021 case Opt_rootcontext:
1022 if (opts->rootcontext)
1023 goto Einval;
1024 opts->rootcontext = s;
1025 break;
1026 case Opt_defcontext:
1027 if (opts->context || opts->defcontext)
1028 goto Einval;
1029 opts->defcontext = s;
1030 break;
1031 }
1032 return 0;
1033Einval:
1034 pr_warn(SEL_MOUNT_FAIL_MSG);
1035 return -EINVAL;
1036}
1037
1038static int selinux_add_mnt_opt(const char *option, const char *val, int len,
1039 void **mnt_opts)
1040{
1041 int token = Opt_error;
1042 int rc, i;
1043
1044 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
1045 if (strcmp(option, tokens[i].name) == 0) {
1046 token = tokens[i].opt;
1047 break;
1048 }
1049 }
1050
1051 if (token == Opt_error)
1052 return -EINVAL;
1053
1054 if (token != Opt_seclabel) {
1055 val = kmemdup_nul(val, len, GFP_KERNEL);
1056 if (!val) {
1057 rc = -ENOMEM;
1058 goto free_opt;
1059 }
1060 }
1061 rc = selinux_add_opt(token, val, mnt_opts);
1062 if (unlikely(rc)) {
1063 kfree(val);
1064 goto free_opt;
1065 }
1066 return rc;
1067
1068free_opt:
1069 if (*mnt_opts) {
1070 selinux_free_mnt_opts(*mnt_opts);
1071 *mnt_opts = NULL;
1072 }
1073 return rc;
1074}
1075
1076static int show_sid(struct seq_file *m, u32 sid)
1077{
1078 char *context = NULL;
1079 u32 len;
1080 int rc;
1081
1082 rc = security_sid_to_context(&selinux_state, sid,
1083 &context, &len);
1084 if (!rc) {
1085 bool has_comma = context && strchr(context, ',');
1086
1087 seq_putc(m, '=');
1088 if (has_comma)
1089 seq_putc(m, '\"');
1090 seq_escape(m, context, "\"\n\\");
1091 if (has_comma)
1092 seq_putc(m, '\"');
1093 }
1094 kfree(context);
1095 return rc;
1096}
1097
1098static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1099{
1100 struct superblock_security_struct *sbsec = sb->s_security;
1101 int rc;
1102
1103 if (!(sbsec->flags & SE_SBINITIALIZED))
1104 return 0;
1105
1106 if (!selinux_state.initialized)
1107 return 0;
1108
1109 if (sbsec->flags & FSCONTEXT_MNT) {
1110 seq_putc(m, ',');
1111 seq_puts(m, FSCONTEXT_STR);
1112 rc = show_sid(m, sbsec->sid);
1113 if (rc)
1114 return rc;
1115 }
1116 if (sbsec->flags & CONTEXT_MNT) {
1117 seq_putc(m, ',');
1118 seq_puts(m, CONTEXT_STR);
1119 rc = show_sid(m, sbsec->mntpoint_sid);
1120 if (rc)
1121 return rc;
1122 }
1123 if (sbsec->flags & DEFCONTEXT_MNT) {
1124 seq_putc(m, ',');
1125 seq_puts(m, DEFCONTEXT_STR);
1126 rc = show_sid(m, sbsec->def_sid);
1127 if (rc)
1128 return rc;
1129 }
1130 if (sbsec->flags & ROOTCONTEXT_MNT) {
1131 struct dentry *root = sbsec->sb->s_root;
1132 struct inode_security_struct *isec = backing_inode_security(root);
1133 seq_putc(m, ',');
1134 seq_puts(m, ROOTCONTEXT_STR);
1135 rc = show_sid(m, isec->sid);
1136 if (rc)
1137 return rc;
1138 }
1139 if (sbsec->flags & SBLABEL_MNT) {
1140 seq_putc(m, ',');
1141 seq_puts(m, SECLABEL_STR);
1142 }
1143 return 0;
1144}
1145
1146static inline u16 inode_mode_to_security_class(umode_t mode)
1147{
1148 switch (mode & S_IFMT) {
1149 case S_IFSOCK:
1150 return SECCLASS_SOCK_FILE;
1151 case S_IFLNK:
1152 return SECCLASS_LNK_FILE;
1153 case S_IFREG:
1154 return SECCLASS_FILE;
1155 case S_IFBLK:
1156 return SECCLASS_BLK_FILE;
1157 case S_IFDIR:
1158 return SECCLASS_DIR;
1159 case S_IFCHR:
1160 return SECCLASS_CHR_FILE;
1161 case S_IFIFO:
1162 return SECCLASS_FIFO_FILE;
1163
1164 }
1165
1166 return SECCLASS_FILE;
1167}
1168
1169static inline int default_protocol_stream(int protocol)
1170{
1171 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1172}
1173
1174static inline int default_protocol_dgram(int protocol)
1175{
1176 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1177}
1178
1179static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1180{
1181 int extsockclass = selinux_policycap_extsockclass();
1182
1183 switch (family) {
1184 case PF_UNIX:
1185 switch (type) {
1186 case SOCK_STREAM:
1187 case SOCK_SEQPACKET:
1188 return SECCLASS_UNIX_STREAM_SOCKET;
1189 case SOCK_DGRAM:
1190 case SOCK_RAW:
1191 return SECCLASS_UNIX_DGRAM_SOCKET;
1192 }
1193 break;
1194 case PF_INET:
1195 case PF_INET6:
1196 switch (type) {
1197 case SOCK_STREAM:
1198 case SOCK_SEQPACKET:
1199 if (default_protocol_stream(protocol))
1200 return SECCLASS_TCP_SOCKET;
1201 else if (extsockclass && protocol == IPPROTO_SCTP)
1202 return SECCLASS_SCTP_SOCKET;
1203 else
1204 return SECCLASS_RAWIP_SOCKET;
1205 case SOCK_DGRAM:
1206 if (default_protocol_dgram(protocol))
1207 return SECCLASS_UDP_SOCKET;
1208 else if (extsockclass && (protocol == IPPROTO_ICMP ||
1209 protocol == IPPROTO_ICMPV6))
1210 return SECCLASS_ICMP_SOCKET;
1211 else
1212 return SECCLASS_RAWIP_SOCKET;
1213 case SOCK_DCCP:
1214 return SECCLASS_DCCP_SOCKET;
1215 default:
1216 return SECCLASS_RAWIP_SOCKET;
1217 }
1218 break;
1219 case PF_NETLINK:
1220 switch (protocol) {
1221 case NETLINK_ROUTE:
1222 return SECCLASS_NETLINK_ROUTE_SOCKET;
1223 case NETLINK_SOCK_DIAG:
1224 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1225 case NETLINK_NFLOG:
1226 return SECCLASS_NETLINK_NFLOG_SOCKET;
1227 case NETLINK_XFRM:
1228 return SECCLASS_NETLINK_XFRM_SOCKET;
1229 case NETLINK_SELINUX:
1230 return SECCLASS_NETLINK_SELINUX_SOCKET;
1231 case NETLINK_ISCSI:
1232 return SECCLASS_NETLINK_ISCSI_SOCKET;
1233 case NETLINK_AUDIT:
1234 return SECCLASS_NETLINK_AUDIT_SOCKET;
1235 case NETLINK_FIB_LOOKUP:
1236 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1237 case NETLINK_CONNECTOR:
1238 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1239 case NETLINK_NETFILTER:
1240 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1241 case NETLINK_DNRTMSG:
1242 return SECCLASS_NETLINK_DNRT_SOCKET;
1243 case NETLINK_KOBJECT_UEVENT:
1244 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1245 case NETLINK_GENERIC:
1246 return SECCLASS_NETLINK_GENERIC_SOCKET;
1247 case NETLINK_SCSITRANSPORT:
1248 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1249 case NETLINK_RDMA:
1250 return SECCLASS_NETLINK_RDMA_SOCKET;
1251 case NETLINK_CRYPTO:
1252 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1253 default:
1254 return SECCLASS_NETLINK_SOCKET;
1255 }
1256 case PF_PACKET:
1257 return SECCLASS_PACKET_SOCKET;
1258 case PF_KEY:
1259 return SECCLASS_KEY_SOCKET;
1260 case PF_APPLETALK:
1261 return SECCLASS_APPLETALK_SOCKET;
1262 }
1263
1264 if (extsockclass) {
1265 switch (family) {
1266 case PF_AX25:
1267 return SECCLASS_AX25_SOCKET;
1268 case PF_IPX:
1269 return SECCLASS_IPX_SOCKET;
1270 case PF_NETROM:
1271 return SECCLASS_NETROM_SOCKET;
1272 case PF_ATMPVC:
1273 return SECCLASS_ATMPVC_SOCKET;
1274 case PF_X25:
1275 return SECCLASS_X25_SOCKET;
1276 case PF_ROSE:
1277 return SECCLASS_ROSE_SOCKET;
1278 case PF_DECnet:
1279 return SECCLASS_DECNET_SOCKET;
1280 case PF_ATMSVC:
1281 return SECCLASS_ATMSVC_SOCKET;
1282 case PF_RDS:
1283 return SECCLASS_RDS_SOCKET;
1284 case PF_IRDA:
1285 return SECCLASS_IRDA_SOCKET;
1286 case PF_PPPOX:
1287 return SECCLASS_PPPOX_SOCKET;
1288 case PF_LLC:
1289 return SECCLASS_LLC_SOCKET;
1290 case PF_CAN:
1291 return SECCLASS_CAN_SOCKET;
1292 case PF_TIPC:
1293 return SECCLASS_TIPC_SOCKET;
1294 case PF_BLUETOOTH:
1295 return SECCLASS_BLUETOOTH_SOCKET;
1296 case PF_IUCV:
1297 return SECCLASS_IUCV_SOCKET;
1298 case PF_RXRPC:
1299 return SECCLASS_RXRPC_SOCKET;
1300 case PF_ISDN:
1301 return SECCLASS_ISDN_SOCKET;
1302 case PF_PHONET:
1303 return SECCLASS_PHONET_SOCKET;
1304 case PF_IEEE802154:
1305 return SECCLASS_IEEE802154_SOCKET;
1306 case PF_CAIF:
1307 return SECCLASS_CAIF_SOCKET;
1308 case PF_ALG:
1309 return SECCLASS_ALG_SOCKET;
1310 case PF_NFC:
1311 return SECCLASS_NFC_SOCKET;
1312 case PF_VSOCK:
1313 return SECCLASS_VSOCK_SOCKET;
1314 case PF_KCM:
1315 return SECCLASS_KCM_SOCKET;
1316 case PF_QIPCRTR:
1317 return SECCLASS_QIPCRTR_SOCKET;
1318 case PF_SMC:
1319 return SECCLASS_SMC_SOCKET;
1320 case PF_XDP:
1321 return SECCLASS_XDP_SOCKET;
1322#if PF_MAX > 45
1323#error New address family defined, please update this function.
1324#endif
1325 }
1326 }
1327
1328 return SECCLASS_SOCKET;
1329}
1330
1331static int selinux_genfs_get_sid(struct dentry *dentry,
1332 u16 tclass,
1333 u16 flags,
1334 u32 *sid)
1335{
1336 int rc;
1337 struct super_block *sb = dentry->d_sb;
1338 char *buffer, *path;
1339
1340 buffer = (char *)__get_free_page(GFP_KERNEL);
1341 if (!buffer)
1342 return -ENOMEM;
1343
1344 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1345 if (IS_ERR(path))
1346 rc = PTR_ERR(path);
1347 else {
1348 if (flags & SE_SBPROC) {
1349 /* each process gets a /proc/PID/ entry. Strip off the
1350 * PID part to get a valid selinux labeling.
1351 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1352 while (path[1] >= '0' && path[1] <= '9') {
1353 path[1] = '/';
1354 path++;
1355 }
1356 }
1357 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1358 path, tclass, sid);
1359 if (rc == -ENOENT) {
1360 /* No match in policy, mark as unlabeled. */
1361 *sid = SECINITSID_UNLABELED;
1362 rc = 0;
1363 }
1364 }
1365 free_page((unsigned long)buffer);
1366 return rc;
1367}
1368
1369static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1370 u32 def_sid, u32 *sid)
1371{
1372#define INITCONTEXTLEN 255
1373 char *context;
1374 unsigned int len;
1375 int rc;
1376
1377 len = INITCONTEXTLEN;
1378 context = kmalloc(len + 1, GFP_NOFS);
1379 if (!context)
1380 return -ENOMEM;
1381
1382 context[len] = '\0';
1383 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1384 if (rc == -ERANGE) {
1385 kfree(context);
1386
1387 /* Need a larger buffer. Query for the right size. */
1388 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1389 if (rc < 0)
1390 return rc;
1391
1392 len = rc;
1393 context = kmalloc(len + 1, GFP_NOFS);
1394 if (!context)
1395 return -ENOMEM;
1396
1397 context[len] = '\0';
1398 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1399 context, len);
1400 }
1401 if (rc < 0) {
1402 kfree(context);
1403 if (rc != -ENODATA) {
1404 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n",
1405 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1406 return rc;
1407 }
1408 *sid = def_sid;
1409 return 0;
1410 }
1411
1412 rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
1413 def_sid, GFP_NOFS);
1414 if (rc) {
1415 char *dev = inode->i_sb->s_id;
1416 unsigned long ino = inode->i_ino;
1417
1418 if (rc == -EINVAL) {
1419 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",
1420 ino, dev, context);
1421 } else {
1422 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1423 __func__, context, -rc, dev, ino);
1424 }
1425 }
1426 kfree(context);
1427 return 0;
1428}
1429
1430/* The inode's security attributes must be initialized before first use. */
1431static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1432{
1433 struct superblock_security_struct *sbsec = NULL;
1434 struct inode_security_struct *isec = selinux_inode(inode);
1435 u32 task_sid, sid = 0;
1436 u16 sclass;
1437 struct dentry *dentry;
1438 int rc = 0;
1439
1440 if (isec->initialized == LABEL_INITIALIZED)
1441 return 0;
1442
1443 spin_lock(&isec->lock);
1444 if (isec->initialized == LABEL_INITIALIZED)
1445 goto out_unlock;
1446
1447 if (isec->sclass == SECCLASS_FILE)
1448 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1449
1450 sbsec = inode->i_sb->s_security;
1451 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1452 /* Defer initialization until selinux_complete_init,
1453 after the initial policy is loaded and the security
1454 server is ready to handle calls. */
1455 spin_lock(&sbsec->isec_lock);
1456 if (list_empty(&isec->list))
1457 list_add(&isec->list, &sbsec->isec_head);
1458 spin_unlock(&sbsec->isec_lock);
1459 goto out_unlock;
1460 }
1461
1462 sclass = isec->sclass;
1463 task_sid = isec->task_sid;
1464 sid = isec->sid;
1465 isec->initialized = LABEL_PENDING;
1466 spin_unlock(&isec->lock);
1467
1468 switch (sbsec->behavior) {
1469 case SECURITY_FS_USE_NATIVE:
1470 break;
1471 case SECURITY_FS_USE_XATTR:
1472 if (!(inode->i_opflags & IOP_XATTR)) {
1473 sid = sbsec->def_sid;
1474 break;
1475 }
1476 /* Need a dentry, since the xattr API requires one.
1477 Life would be simpler if we could just pass the inode. */
1478 if (opt_dentry) {
1479 /* Called from d_instantiate or d_splice_alias. */
1480 dentry = dget(opt_dentry);
1481 } else {
1482 /*
1483 * Called from selinux_complete_init, try to find a dentry.
1484 * Some filesystems really want a connected one, so try
1485 * that first. We could split SECURITY_FS_USE_XATTR in
1486 * two, depending upon that...
1487 */
1488 dentry = d_find_alias(inode);
1489 if (!dentry)
1490 dentry = d_find_any_alias(inode);
1491 }
1492 if (!dentry) {
1493 /*
1494 * this is can be hit on boot when a file is accessed
1495 * before the policy is loaded. When we load policy we
1496 * may find inodes that have no dentry on the
1497 * sbsec->isec_head list. No reason to complain as these
1498 * will get fixed up the next time we go through
1499 * inode_doinit with a dentry, before these inodes could
1500 * be used again by userspace.
1501 */
1502 goto out;
1503 }
1504
1505 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1506 &sid);
1507 dput(dentry);
1508 if (rc)
1509 goto out;
1510 break;
1511 case SECURITY_FS_USE_TASK:
1512 sid = task_sid;
1513 break;
1514 case SECURITY_FS_USE_TRANS:
1515 /* Default to the fs SID. */
1516 sid = sbsec->sid;
1517
1518 /* Try to obtain a transition SID. */
1519 rc = security_transition_sid(&selinux_state, task_sid, sid,
1520 sclass, NULL, &sid);
1521 if (rc)
1522 goto out;
1523 break;
1524 case SECURITY_FS_USE_MNTPOINT:
1525 sid = sbsec->mntpoint_sid;
1526 break;
1527 default:
1528 /* Default to the fs superblock SID. */
1529 sid = sbsec->sid;
1530
1531 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1532 /* We must have a dentry to determine the label on
1533 * procfs inodes */
1534 if (opt_dentry) {
1535 /* Called from d_instantiate or
1536 * d_splice_alias. */
1537 dentry = dget(opt_dentry);
1538 } else {
1539 /* Called from selinux_complete_init, try to
1540 * find a dentry. Some filesystems really want
1541 * a connected one, so try that first.
1542 */
1543 dentry = d_find_alias(inode);
1544 if (!dentry)
1545 dentry = d_find_any_alias(inode);
1546 }
1547 /*
1548 * This can be hit on boot when a file is accessed
1549 * before the policy is loaded. When we load policy we
1550 * may find inodes that have no dentry on the
1551 * sbsec->isec_head list. No reason to complain as
1552 * these will get fixed up the next time we go through
1553 * inode_doinit() with a dentry, before these inodes
1554 * could be used again by userspace.
1555 */
1556 if (!dentry)
1557 goto out;
1558 rc = selinux_genfs_get_sid(dentry, sclass,
1559 sbsec->flags, &sid);
1560 if (rc) {
1561 dput(dentry);
1562 goto out;
1563 }
1564
1565 if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1566 (inode->i_opflags & IOP_XATTR)) {
1567 rc = inode_doinit_use_xattr(inode, dentry,
1568 sid, &sid);
1569 if (rc) {
1570 dput(dentry);
1571 goto out;
1572 }
1573 }
1574 dput(dentry);
1575 }
1576 break;
1577 }
1578
1579out:
1580 spin_lock(&isec->lock);
1581 if (isec->initialized == LABEL_PENDING) {
1582 if (!sid || rc) {
1583 isec->initialized = LABEL_INVALID;
1584 goto out_unlock;
1585 }
1586
1587 isec->initialized = LABEL_INITIALIZED;
1588 isec->sid = sid;
1589 }
1590
1591out_unlock:
1592 spin_unlock(&isec->lock);
1593 return rc;
1594}
1595
1596/* Convert a Linux signal to an access vector. */
1597static inline u32 signal_to_av(int sig)
1598{
1599 u32 perm = 0;
1600
1601 switch (sig) {
1602 case SIGCHLD:
1603 /* Commonly granted from child to parent. */
1604 perm = PROCESS__SIGCHLD;
1605 break;
1606 case SIGKILL:
1607 /* Cannot be caught or ignored */
1608 perm = PROCESS__SIGKILL;
1609 break;
1610 case SIGSTOP:
1611 /* Cannot be caught or ignored */
1612 perm = PROCESS__SIGSTOP;
1613 break;
1614 default:
1615 /* All other signals. */
1616 perm = PROCESS__SIGNAL;
1617 break;
1618 }
1619
1620 return perm;
1621}
1622
1623#if CAP_LAST_CAP > 63
1624#error Fix SELinux to handle capabilities > 63.
1625#endif
1626
1627/* Check whether a task is allowed to use a capability. */
1628static int cred_has_capability(const struct cred *cred,
1629 int cap, unsigned int opts, bool initns)
1630{
1631 struct common_audit_data ad;
1632 struct av_decision avd;
1633 u16 sclass;
1634 u32 sid = cred_sid(cred);
1635 u32 av = CAP_TO_MASK(cap);
1636 int rc;
1637
1638 ad.type = LSM_AUDIT_DATA_CAP;
1639 ad.u.cap = cap;
1640
1641 switch (CAP_TO_INDEX(cap)) {
1642 case 0:
1643 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1644 break;
1645 case 1:
1646 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1647 break;
1648 default:
1649 pr_err("SELinux: out of range capability %d\n", cap);
1650 BUG();
1651 return -EINVAL;
1652 }
1653
1654 rc = avc_has_perm_noaudit(&selinux_state,
1655 sid, sid, sclass, av, 0, &avd);
1656 if (!(opts & CAP_OPT_NOAUDIT)) {
1657 int rc2 = avc_audit(&selinux_state,
1658 sid, sid, sclass, av, &avd, rc, &ad, 0);
1659 if (rc2)
1660 return rc2;
1661 }
1662 return rc;
1663}
1664
1665/* Check whether a task has a particular permission to an inode.
1666 The 'adp' parameter is optional and allows other audit
1667 data to be passed (e.g. the dentry). */
1668static int inode_has_perm(const struct cred *cred,
1669 struct inode *inode,
1670 u32 perms,
1671 struct common_audit_data *adp)
1672{
1673 struct inode_security_struct *isec;
1674 u32 sid;
1675
1676 validate_creds(cred);
1677
1678 if (unlikely(IS_PRIVATE(inode)))
1679 return 0;
1680
1681 sid = cred_sid(cred);
1682 isec = selinux_inode(inode);
1683
1684 return avc_has_perm(&selinux_state,
1685 sid, isec->sid, isec->sclass, perms, adp);
1686}
1687
1688/* Same as inode_has_perm, but pass explicit audit data containing
1689 the dentry to help the auditing code to more easily generate the
1690 pathname if needed. */
1691static inline int dentry_has_perm(const struct cred *cred,
1692 struct dentry *dentry,
1693 u32 av)
1694{
1695 struct inode *inode = d_backing_inode(dentry);
1696 struct common_audit_data ad;
1697
1698 ad.type = LSM_AUDIT_DATA_DENTRY;
1699 ad.u.dentry = dentry;
1700 __inode_security_revalidate(inode, dentry, true);
1701 return inode_has_perm(cred, inode, av, &ad);
1702}
1703
1704/* Same as inode_has_perm, but pass explicit audit data containing
1705 the path to help the auditing code to more easily generate the
1706 pathname if needed. */
1707static inline int path_has_perm(const struct cred *cred,
1708 const struct path *path,
1709 u32 av)
1710{
1711 struct inode *inode = d_backing_inode(path->dentry);
1712 struct common_audit_data ad;
1713
1714 ad.type = LSM_AUDIT_DATA_PATH;
1715 ad.u.path = *path;
1716 __inode_security_revalidate(inode, path->dentry, true);
1717 return inode_has_perm(cred, inode, av, &ad);
1718}
1719
1720/* Same as path_has_perm, but uses the inode from the file struct. */
1721static inline int file_path_has_perm(const struct cred *cred,
1722 struct file *file,
1723 u32 av)
1724{
1725 struct common_audit_data ad;
1726
1727 ad.type = LSM_AUDIT_DATA_FILE;
1728 ad.u.file = file;
1729 return inode_has_perm(cred, file_inode(file), av, &ad);
1730}
1731
1732#ifdef CONFIG_BPF_SYSCALL
1733static int bpf_fd_pass(struct file *file, u32 sid);
1734#endif
1735
1736/* Check whether a task can use an open file descriptor to
1737 access an inode in a given way. Check access to the
1738 descriptor itself, and then use dentry_has_perm to
1739 check a particular permission to the file.
1740 Access to the descriptor is implicitly granted if it
1741 has the same SID as the process. If av is zero, then
1742 access to the file is not checked, e.g. for cases
1743 where only the descriptor is affected like seek. */
1744static int file_has_perm(const struct cred *cred,
1745 struct file *file,
1746 u32 av)
1747{
1748 struct file_security_struct *fsec = selinux_file(file);
1749 struct inode *inode = file_inode(file);
1750 struct common_audit_data ad;
1751 u32 sid = cred_sid(cred);
1752 int rc;
1753
1754 ad.type = LSM_AUDIT_DATA_FILE;
1755 ad.u.file = file;
1756
1757 if (sid != fsec->sid) {
1758 rc = avc_has_perm(&selinux_state,
1759 sid, fsec->sid,
1760 SECCLASS_FD,
1761 FD__USE,
1762 &ad);
1763 if (rc)
1764 goto out;
1765 }
1766
1767#ifdef CONFIG_BPF_SYSCALL
1768 rc = bpf_fd_pass(file, cred_sid(cred));
1769 if (rc)
1770 return rc;
1771#endif
1772
1773 /* av is zero if only checking access to the descriptor. */
1774 rc = 0;
1775 if (av)
1776 rc = inode_has_perm(cred, inode, av, &ad);
1777
1778out:
1779 return rc;
1780}
1781
1782/*
1783 * Determine the label for an inode that might be unioned.
1784 */
1785static int
1786selinux_determine_inode_label(const struct task_security_struct *tsec,
1787 struct inode *dir,
1788 const struct qstr *name, u16 tclass,
1789 u32 *_new_isid)
1790{
1791 const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1792
1793 if ((sbsec->flags & SE_SBINITIALIZED) &&
1794 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1795 *_new_isid = sbsec->mntpoint_sid;
1796 } else if ((sbsec->flags & SBLABEL_MNT) &&
1797 tsec->create_sid) {
1798 *_new_isid = tsec->create_sid;
1799 } else {
1800 const struct inode_security_struct *dsec = inode_security(dir);
1801 return security_transition_sid(&selinux_state, tsec->sid,
1802 dsec->sid, tclass,
1803 name, _new_isid);
1804 }
1805
1806 return 0;
1807}
1808
1809/* Check whether a task can create a file. */
1810static int may_create(struct inode *dir,
1811 struct dentry *dentry,
1812 u16 tclass)
1813{
1814 const struct task_security_struct *tsec = selinux_cred(current_cred());
1815 struct inode_security_struct *dsec;
1816 struct superblock_security_struct *sbsec;
1817 u32 sid, newsid;
1818 struct common_audit_data ad;
1819 int rc;
1820
1821 dsec = inode_security(dir);
1822 sbsec = dir->i_sb->s_security;
1823
1824 sid = tsec->sid;
1825
1826 ad.type = LSM_AUDIT_DATA_DENTRY;
1827 ad.u.dentry = dentry;
1828
1829 rc = avc_has_perm(&selinux_state,
1830 sid, dsec->sid, SECCLASS_DIR,
1831 DIR__ADD_NAME | DIR__SEARCH,
1832 &ad);
1833 if (rc)
1834 return rc;
1835
1836 rc = selinux_determine_inode_label(selinux_cred(current_cred()), dir,
1837 &dentry->d_name, tclass, &newsid);
1838 if (rc)
1839 return rc;
1840
1841 rc = avc_has_perm(&selinux_state,
1842 sid, newsid, tclass, FILE__CREATE, &ad);
1843 if (rc)
1844 return rc;
1845
1846 return avc_has_perm(&selinux_state,
1847 newsid, sbsec->sid,
1848 SECCLASS_FILESYSTEM,
1849 FILESYSTEM__ASSOCIATE, &ad);
1850}
1851
1852#define MAY_LINK 0
1853#define MAY_UNLINK 1
1854#define MAY_RMDIR 2
1855
1856/* Check whether a task can link, unlink, or rmdir a file/directory. */
1857static int may_link(struct inode *dir,
1858 struct dentry *dentry,
1859 int kind)
1860
1861{
1862 struct inode_security_struct *dsec, *isec;
1863 struct common_audit_data ad;
1864 u32 sid = current_sid();
1865 u32 av;
1866 int rc;
1867
1868 dsec = inode_security(dir);
1869 isec = backing_inode_security(dentry);
1870
1871 ad.type = LSM_AUDIT_DATA_DENTRY;
1872 ad.u.dentry = dentry;
1873
1874 av = DIR__SEARCH;
1875 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1876 rc = avc_has_perm(&selinux_state,
1877 sid, dsec->sid, SECCLASS_DIR, av, &ad);
1878 if (rc)
1879 return rc;
1880
1881 switch (kind) {
1882 case MAY_LINK:
1883 av = FILE__LINK;
1884 break;
1885 case MAY_UNLINK:
1886 av = FILE__UNLINK;
1887 break;
1888 case MAY_RMDIR:
1889 av = DIR__RMDIR;
1890 break;
1891 default:
1892 pr_warn("SELinux: %s: unrecognized kind %d\n",
1893 __func__, kind);
1894 return 0;
1895 }
1896
1897 rc = avc_has_perm(&selinux_state,
1898 sid, isec->sid, isec->sclass, av, &ad);
1899 return rc;
1900}
1901
1902static inline int may_rename(struct inode *old_dir,
1903 struct dentry *old_dentry,
1904 struct inode *new_dir,
1905 struct dentry *new_dentry)
1906{
1907 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1908 struct common_audit_data ad;
1909 u32 sid = current_sid();
1910 u32 av;
1911 int old_is_dir, new_is_dir;
1912 int rc;
1913
1914 old_dsec = inode_security(old_dir);
1915 old_isec = backing_inode_security(old_dentry);
1916 old_is_dir = d_is_dir(old_dentry);
1917 new_dsec = inode_security(new_dir);
1918
1919 ad.type = LSM_AUDIT_DATA_DENTRY;
1920
1921 ad.u.dentry = old_dentry;
1922 rc = avc_has_perm(&selinux_state,
1923 sid, old_dsec->sid, SECCLASS_DIR,
1924 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1925 if (rc)
1926 return rc;
1927 rc = avc_has_perm(&selinux_state,
1928 sid, old_isec->sid,
1929 old_isec->sclass, FILE__RENAME, &ad);
1930 if (rc)
1931 return rc;
1932 if (old_is_dir && new_dir != old_dir) {
1933 rc = avc_has_perm(&selinux_state,
1934 sid, old_isec->sid,
1935 old_isec->sclass, DIR__REPARENT, &ad);
1936 if (rc)
1937 return rc;
1938 }
1939
1940 ad.u.dentry = new_dentry;
1941 av = DIR__ADD_NAME | DIR__SEARCH;
1942 if (d_is_positive(new_dentry))
1943 av |= DIR__REMOVE_NAME;
1944 rc = avc_has_perm(&selinux_state,
1945 sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1946 if (rc)
1947 return rc;
1948 if (d_is_positive(new_dentry)) {
1949 new_isec = backing_inode_security(new_dentry);
1950 new_is_dir = d_is_dir(new_dentry);
1951 rc = avc_has_perm(&selinux_state,
1952 sid, new_isec->sid,
1953 new_isec->sclass,
1954 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1955 if (rc)
1956 return rc;
1957 }
1958
1959 return 0;
1960}
1961
1962/* Check whether a task can perform a filesystem operation. */
1963static int superblock_has_perm(const struct cred *cred,
1964 struct super_block *sb,
1965 u32 perms,
1966 struct common_audit_data *ad)
1967{
1968 struct superblock_security_struct *sbsec;
1969 u32 sid = cred_sid(cred);
1970
1971 sbsec = sb->s_security;
1972 return avc_has_perm(&selinux_state,
1973 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1974}
1975
1976/* Convert a Linux mode and permission mask to an access vector. */
1977static inline u32 file_mask_to_av(int mode, int mask)
1978{
1979 u32 av = 0;
1980
1981 if (!S_ISDIR(mode)) {
1982 if (mask & MAY_EXEC)
1983 av |= FILE__EXECUTE;
1984 if (mask & MAY_READ)
1985 av |= FILE__READ;
1986
1987 if (mask & MAY_APPEND)
1988 av |= FILE__APPEND;
1989 else if (mask & MAY_WRITE)
1990 av |= FILE__WRITE;
1991
1992 } else {
1993 if (mask & MAY_EXEC)
1994 av |= DIR__SEARCH;
1995 if (mask & MAY_WRITE)
1996 av |= DIR__WRITE;
1997 if (mask & MAY_READ)
1998 av |= DIR__READ;
1999 }
2000
2001 return av;
2002}
2003
2004/* Convert a Linux file to an access vector. */
2005static inline u32 file_to_av(struct file *file)
2006{
2007 u32 av = 0;
2008
2009 if (file->f_mode & FMODE_READ)
2010 av |= FILE__READ;
2011 if (file->f_mode & FMODE_WRITE) {
2012 if (file->f_flags & O_APPEND)
2013 av |= FILE__APPEND;
2014 else
2015 av |= FILE__WRITE;
2016 }
2017 if (!av) {
2018 /*
2019 * Special file opened with flags 3 for ioctl-only use.
2020 */
2021 av = FILE__IOCTL;
2022 }
2023
2024 return av;
2025}
2026
2027/*
2028 * Convert a file to an access vector and include the correct open
2029 * open permission.
2030 */
2031static inline u32 open_file_to_av(struct file *file)
2032{
2033 u32 av = file_to_av(file);
2034 struct inode *inode = file_inode(file);
2035
2036 if (selinux_policycap_openperm() &&
2037 inode->i_sb->s_magic != SOCKFS_MAGIC)
2038 av |= FILE__OPEN;
2039
2040 return av;
2041}
2042
2043/* Hook functions begin here. */
2044
2045static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2046{
2047 u32 mysid = current_sid();
2048 u32 mgrsid = task_sid(mgr);
2049
2050 return avc_has_perm(&selinux_state,
2051 mysid, mgrsid, SECCLASS_BINDER,
2052 BINDER__SET_CONTEXT_MGR, NULL);
2053}
2054
2055static int selinux_binder_transaction(struct task_struct *from,
2056 struct task_struct *to)
2057{
2058 u32 mysid = current_sid();
2059 u32 fromsid = task_sid(from);
2060 u32 tosid = task_sid(to);
2061 int rc;
2062
2063 if (mysid != fromsid) {
2064 rc = avc_has_perm(&selinux_state,
2065 mysid, fromsid, SECCLASS_BINDER,
2066 BINDER__IMPERSONATE, NULL);
2067 if (rc)
2068 return rc;
2069 }
2070
2071 return avc_has_perm(&selinux_state,
2072 fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2073 NULL);
2074}
2075
2076static int selinux_binder_transfer_binder(struct task_struct *from,
2077 struct task_struct *to)
2078{
2079 u32 fromsid = task_sid(from);
2080 u32 tosid = task_sid(to);
2081
2082 return avc_has_perm(&selinux_state,
2083 fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2084 NULL);
2085}
2086
2087static int selinux_binder_transfer_file(struct task_struct *from,
2088 struct task_struct *to,
2089 struct file *file)
2090{
2091 u32 sid = task_sid(to);
2092 struct file_security_struct *fsec = selinux_file(file);
2093 struct dentry *dentry = file->f_path.dentry;
2094 struct inode_security_struct *isec;
2095 struct common_audit_data ad;
2096 int rc;
2097
2098 ad.type = LSM_AUDIT_DATA_PATH;
2099 ad.u.path = file->f_path;
2100
2101 if (sid != fsec->sid) {
2102 rc = avc_has_perm(&selinux_state,
2103 sid, fsec->sid,
2104 SECCLASS_FD,
2105 FD__USE,
2106 &ad);
2107 if (rc)
2108 return rc;
2109 }
2110
2111#ifdef CONFIG_BPF_SYSCALL
2112 rc = bpf_fd_pass(file, sid);
2113 if (rc)
2114 return rc;
2115#endif
2116
2117 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2118 return 0;
2119
2120 isec = backing_inode_security(dentry);
2121 return avc_has_perm(&selinux_state,
2122 sid, isec->sid, isec->sclass, file_to_av(file),
2123 &ad);
2124}
2125
2126static int selinux_ptrace_access_check(struct task_struct *child,
2127 unsigned int mode)
2128{
2129 u32 sid = current_sid();
2130 u32 csid = task_sid(child);
2131
2132 if (mode & PTRACE_MODE_READ)
2133 return avc_has_perm(&selinux_state,
2134 sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2135
2136 return avc_has_perm(&selinux_state,
2137 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2138}
2139
2140static int selinux_ptrace_traceme(struct task_struct *parent)
2141{
2142 return avc_has_perm(&selinux_state,
2143 task_sid(parent), current_sid(), SECCLASS_PROCESS,
2144 PROCESS__PTRACE, NULL);
2145}
2146
2147static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2148 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2149{
2150 return avc_has_perm(&selinux_state,
2151 current_sid(), task_sid(target), SECCLASS_PROCESS,
2152 PROCESS__GETCAP, NULL);
2153}
2154
2155static int selinux_capset(struct cred *new, const struct cred *old,
2156 const kernel_cap_t *effective,
2157 const kernel_cap_t *inheritable,
2158 const kernel_cap_t *permitted)
2159{
2160 return avc_has_perm(&selinux_state,
2161 cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2162 PROCESS__SETCAP, NULL);
2163}
2164
2165/*
2166 * (This comment used to live with the selinux_task_setuid hook,
2167 * which was removed).
2168 *
2169 * Since setuid only affects the current process, and since the SELinux
2170 * controls are not based on the Linux identity attributes, SELinux does not
2171 * need to control this operation. However, SELinux does control the use of
2172 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2173 */
2174
2175static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2176 int cap, unsigned int opts)
2177{
2178 return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2179}
2180
2181static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2182{
2183 const struct cred *cred = current_cred();
2184 int rc = 0;
2185
2186 if (!sb)
2187 return 0;
2188
2189 switch (cmds) {
2190 case Q_SYNC:
2191 case Q_QUOTAON:
2192 case Q_QUOTAOFF:
2193 case Q_SETINFO:
2194 case Q_SETQUOTA:
2195 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2196 break;
2197 case Q_GETFMT:
2198 case Q_GETINFO:
2199 case Q_GETQUOTA:
2200 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2201 break;
2202 default:
2203 rc = 0; /* let the kernel handle invalid cmds */
2204 break;
2205 }
2206 return rc;
2207}
2208
2209static int selinux_quota_on(struct dentry *dentry)
2210{
2211 const struct cred *cred = current_cred();
2212
2213 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2214}
2215
2216static int selinux_syslog(int type)
2217{
2218 switch (type) {
2219 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2220 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2221 return avc_has_perm(&selinux_state,
2222 current_sid(), SECINITSID_KERNEL,
2223 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2224 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2225 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2226 /* Set level of messages printed to console */
2227 case SYSLOG_ACTION_CONSOLE_LEVEL:
2228 return avc_has_perm(&selinux_state,
2229 current_sid(), SECINITSID_KERNEL,
2230 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2231 NULL);
2232 }
2233 /* All other syslog types */
2234 return avc_has_perm(&selinux_state,
2235 current_sid(), SECINITSID_KERNEL,
2236 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2237}
2238
2239/*
2240 * Check that a process has enough memory to allocate a new virtual
2241 * mapping. 0 means there is enough memory for the allocation to
2242 * succeed and -ENOMEM implies there is not.
2243 *
2244 * Do not audit the selinux permission check, as this is applied to all
2245 * processes that allocate mappings.
2246 */
2247static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2248{
2249 int rc, cap_sys_admin = 0;
2250
2251 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2252 CAP_OPT_NOAUDIT, true);
2253 if (rc == 0)
2254 cap_sys_admin = 1;
2255
2256 return cap_sys_admin;
2257}
2258
2259/* binprm security operations */
2260
2261static u32 ptrace_parent_sid(void)
2262{
2263 u32 sid = 0;
2264 struct task_struct *tracer;
2265
2266 rcu_read_lock();
2267 tracer = ptrace_parent(current);
2268 if (tracer)
2269 sid = task_sid(tracer);
2270 rcu_read_unlock();
2271
2272 return sid;
2273}
2274
2275static int check_nnp_nosuid(const struct linux_binprm *bprm,
2276 const struct task_security_struct *old_tsec,
2277 const struct task_security_struct *new_tsec)
2278{
2279 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2280 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2281 int rc;
2282 u32 av;
2283
2284 if (!nnp && !nosuid)
2285 return 0; /* neither NNP nor nosuid */
2286
2287 if (new_tsec->sid == old_tsec->sid)
2288 return 0; /* No change in credentials */
2289
2290 /*
2291 * If the policy enables the nnp_nosuid_transition policy capability,
2292 * then we permit transitions under NNP or nosuid if the
2293 * policy allows the corresponding permission between
2294 * the old and new contexts.
2295 */
2296 if (selinux_policycap_nnp_nosuid_transition()) {
2297 av = 0;
2298 if (nnp)
2299 av |= PROCESS2__NNP_TRANSITION;
2300 if (nosuid)
2301 av |= PROCESS2__NOSUID_TRANSITION;
2302 rc = avc_has_perm(&selinux_state,
2303 old_tsec->sid, new_tsec->sid,
2304 SECCLASS_PROCESS2, av, NULL);
2305 if (!rc)
2306 return 0;
2307 }
2308
2309 /*
2310 * We also permit NNP or nosuid transitions to bounded SIDs,
2311 * i.e. SIDs that are guaranteed to only be allowed a subset
2312 * of the permissions of the current SID.
2313 */
2314 rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2315 new_tsec->sid);
2316 if (!rc)
2317 return 0;
2318
2319 /*
2320 * On failure, preserve the errno values for NNP vs nosuid.
2321 * NNP: Operation not permitted for caller.
2322 * nosuid: Permission denied to file.
2323 */
2324 if (nnp)
2325 return -EPERM;
2326 return -EACCES;
2327}
2328
2329static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2330{
2331 const struct task_security_struct *old_tsec;
2332 struct task_security_struct *new_tsec;
2333 struct inode_security_struct *isec;
2334 struct common_audit_data ad;
2335 struct inode *inode = file_inode(bprm->file);
2336 int rc;
2337
2338 /* SELinux context only depends on initial program or script and not
2339 * the script interpreter */
2340 if (bprm->called_set_creds)
2341 return 0;
2342
2343 old_tsec = selinux_cred(current_cred());
2344 new_tsec = selinux_cred(bprm->cred);
2345 isec = inode_security(inode);
2346
2347 /* Default to the current task SID. */
2348 new_tsec->sid = old_tsec->sid;
2349 new_tsec->osid = old_tsec->sid;
2350
2351 /* Reset fs, key, and sock SIDs on execve. */
2352 new_tsec->create_sid = 0;
2353 new_tsec->keycreate_sid = 0;
2354 new_tsec->sockcreate_sid = 0;
2355
2356 if (old_tsec->exec_sid) {
2357 new_tsec->sid = old_tsec->exec_sid;
2358 /* Reset exec SID on execve. */
2359 new_tsec->exec_sid = 0;
2360
2361 /* Fail on NNP or nosuid if not an allowed transition. */
2362 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2363 if (rc)
2364 return rc;
2365 } else {
2366 /* Check for a default transition on this program. */
2367 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2368 isec->sid, SECCLASS_PROCESS, NULL,
2369 &new_tsec->sid);
2370 if (rc)
2371 return rc;
2372
2373 /*
2374 * Fallback to old SID on NNP or nosuid if not an allowed
2375 * transition.
2376 */
2377 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2378 if (rc)
2379 new_tsec->sid = old_tsec->sid;
2380 }
2381
2382 ad.type = LSM_AUDIT_DATA_FILE;
2383 ad.u.file = bprm->file;
2384
2385 if (new_tsec->sid == old_tsec->sid) {
2386 rc = avc_has_perm(&selinux_state,
2387 old_tsec->sid, isec->sid,
2388 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2389 if (rc)
2390 return rc;
2391 } else {
2392 /* Check permissions for the transition. */
2393 rc = avc_has_perm(&selinux_state,
2394 old_tsec->sid, new_tsec->sid,
2395 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2396 if (rc)
2397 return rc;
2398
2399 rc = avc_has_perm(&selinux_state,
2400 new_tsec->sid, isec->sid,
2401 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2402 if (rc)
2403 return rc;
2404
2405 /* Check for shared state */
2406 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2407 rc = avc_has_perm(&selinux_state,
2408 old_tsec->sid, new_tsec->sid,
2409 SECCLASS_PROCESS, PROCESS__SHARE,
2410 NULL);
2411 if (rc)
2412 return -EPERM;
2413 }
2414
2415 /* Make sure that anyone attempting to ptrace over a task that
2416 * changes its SID has the appropriate permit */
2417 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2418 u32 ptsid = ptrace_parent_sid();
2419 if (ptsid != 0) {
2420 rc = avc_has_perm(&selinux_state,
2421 ptsid, new_tsec->sid,
2422 SECCLASS_PROCESS,
2423 PROCESS__PTRACE, NULL);
2424 if (rc)
2425 return -EPERM;
2426 }
2427 }
2428
2429 /* Clear any possibly unsafe personality bits on exec: */
2430 bprm->per_clear |= PER_CLEAR_ON_SETID;
2431
2432 /* Enable secure mode for SIDs transitions unless
2433 the noatsecure permission is granted between
2434 the two SIDs, i.e. ahp returns 0. */
2435 rc = avc_has_perm(&selinux_state,
2436 old_tsec->sid, new_tsec->sid,
2437 SECCLASS_PROCESS, PROCESS__NOATSECURE,
2438 NULL);
2439 bprm->secureexec |= !!rc;
2440 }
2441
2442 return 0;
2443}
2444
2445static int match_file(const void *p, struct file *file, unsigned fd)
2446{
2447 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2448}
2449
2450/* Derived from fs/exec.c:flush_old_files. */
2451static inline void flush_unauthorized_files(const struct cred *cred,
2452 struct files_struct *files)
2453{
2454 struct file *file, *devnull = NULL;
2455 struct tty_struct *tty;
2456 int drop_tty = 0;
2457 unsigned n;
2458
2459 tty = get_current_tty();
2460 if (tty) {
2461 spin_lock(&tty->files_lock);
2462 if (!list_empty(&tty->tty_files)) {
2463 struct tty_file_private *file_priv;
2464
2465 /* Revalidate access to controlling tty.
2466 Use file_path_has_perm on the tty path directly
2467 rather than using file_has_perm, as this particular
2468 open file may belong to another process and we are
2469 only interested in the inode-based check here. */
2470 file_priv = list_first_entry(&tty->tty_files,
2471 struct tty_file_private, list);
2472 file = file_priv->file;
2473 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2474 drop_tty = 1;
2475 }
2476 spin_unlock(&tty->files_lock);
2477 tty_kref_put(tty);
2478 }
2479 /* Reset controlling tty. */
2480 if (drop_tty)
2481 no_tty();
2482
2483 /* Revalidate access to inherited open files. */
2484 n = iterate_fd(files, 0, match_file, cred);
2485 if (!n) /* none found? */
2486 return;
2487
2488 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2489 if (IS_ERR(devnull))
2490 devnull = NULL;
2491 /* replace all the matching ones with this */
2492 do {
2493 replace_fd(n - 1, devnull, 0);
2494 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2495 if (devnull)
2496 fput(devnull);
2497}
2498
2499/*
2500 * Prepare a process for imminent new credential changes due to exec
2501 */
2502static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2503{
2504 struct task_security_struct *new_tsec;
2505 struct rlimit *rlim, *initrlim;
2506 int rc, i;
2507
2508 new_tsec = selinux_cred(bprm->cred);
2509 if (new_tsec->sid == new_tsec->osid)
2510 return;
2511
2512 /* Close files for which the new task SID is not authorized. */
2513 flush_unauthorized_files(bprm->cred, current->files);
2514
2515 /* Always clear parent death signal on SID transitions. */
2516 current->pdeath_signal = 0;
2517
2518 /* Check whether the new SID can inherit resource limits from the old
2519 * SID. If not, reset all soft limits to the lower of the current
2520 * task's hard limit and the init task's soft limit.
2521 *
2522 * Note that the setting of hard limits (even to lower them) can be
2523 * controlled by the setrlimit check. The inclusion of the init task's
2524 * soft limit into the computation is to avoid resetting soft limits
2525 * higher than the default soft limit for cases where the default is
2526 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2527 */
2528 rc = avc_has_perm(&selinux_state,
2529 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2530 PROCESS__RLIMITINH, NULL);
2531 if (rc) {
2532 /* protect against do_prlimit() */
2533 task_lock(current);
2534 for (i = 0; i < RLIM_NLIMITS; i++) {
2535 rlim = current->signal->rlim + i;
2536 initrlim = init_task.signal->rlim + i;
2537 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2538 }
2539 task_unlock(current);
2540 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2541 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2542 }
2543}
2544
2545/*
2546 * Clean up the process immediately after the installation of new credentials
2547 * due to exec
2548 */
2549static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2550{
2551 const struct task_security_struct *tsec = selinux_cred(current_cred());
2552 struct itimerval itimer;
2553 u32 osid, sid;
2554 int rc, i;
2555
2556 osid = tsec->osid;
2557 sid = tsec->sid;
2558
2559 if (sid == osid)
2560 return;
2561
2562 /* Check whether the new SID can inherit signal state from the old SID.
2563 * If not, clear itimers to avoid subsequent signal generation and
2564 * flush and unblock signals.
2565 *
2566 * This must occur _after_ the task SID has been updated so that any
2567 * kill done after the flush will be checked against the new SID.
2568 */
2569 rc = avc_has_perm(&selinux_state,
2570 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2571 if (rc) {
2572 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
2573 memset(&itimer, 0, sizeof itimer);
2574 for (i = 0; i < 3; i++)
2575 do_setitimer(i, &itimer, NULL);
2576 }
2577 spin_lock_irq(¤t->sighand->siglock);
2578 if (!fatal_signal_pending(current)) {
2579 flush_sigqueue(¤t->pending);
2580 flush_sigqueue(¤t->signal->shared_pending);
2581 flush_signal_handlers(current, 1);
2582 sigemptyset(¤t->blocked);
2583 recalc_sigpending();
2584 }
2585 spin_unlock_irq(¤t->sighand->siglock);
2586 }
2587
2588 /* Wake up the parent if it is waiting so that it can recheck
2589 * wait permission to the new task SID. */
2590 read_lock(&tasklist_lock);
2591 __wake_up_parent(current, current->real_parent);
2592 read_unlock(&tasklist_lock);
2593}
2594
2595/* superblock security operations */
2596
2597static int selinux_sb_alloc_security(struct super_block *sb)
2598{
2599 return superblock_alloc_security(sb);
2600}
2601
2602static void selinux_sb_free_security(struct super_block *sb)
2603{
2604 superblock_free_security(sb);
2605}
2606
2607static inline int opt_len(const char *s)
2608{
2609 bool open_quote = false;
2610 int len;
2611 char c;
2612
2613 for (len = 0; (c = s[len]) != '\0'; len++) {
2614 if (c == '"')
2615 open_quote = !open_quote;
2616 if (c == ',' && !open_quote)
2617 break;
2618 }
2619 return len;
2620}
2621
2622static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2623{
2624 char *from = options;
2625 char *to = options;
2626 bool first = true;
2627 int rc;
2628
2629 while (1) {
2630 int len = opt_len(from);
2631 int token;
2632 char *arg = NULL;
2633
2634 token = match_opt_prefix(from, len, &arg);
2635
2636 if (token != Opt_error) {
2637 char *p, *q;
2638
2639 /* strip quotes */
2640 if (arg) {
2641 for (p = q = arg; p < from + len; p++) {
2642 char c = *p;
2643 if (c != '"')
2644 *q++ = c;
2645 }
2646 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2647 if (!arg) {
2648 rc = -ENOMEM;
2649 goto free_opt;
2650 }
2651 }
2652 rc = selinux_add_opt(token, arg, mnt_opts);
2653 if (unlikely(rc)) {
2654 kfree(arg);
2655 goto free_opt;
2656 }
2657 } else {
2658 if (!first) { // copy with preceding comma
2659 from--;
2660 len++;
2661 }
2662 if (to != from)
2663 memmove(to, from, len);
2664 to += len;
2665 first = false;
2666 }
2667 if (!from[len])
2668 break;
2669 from += len + 1;
2670 }
2671 *to = '\0';
2672 return 0;
2673
2674free_opt:
2675 if (*mnt_opts) {
2676 selinux_free_mnt_opts(*mnt_opts);
2677 *mnt_opts = NULL;
2678 }
2679 return rc;
2680}
2681
2682static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2683{
2684 struct selinux_mnt_opts *opts = mnt_opts;
2685 struct superblock_security_struct *sbsec = sb->s_security;
2686 u32 sid;
2687 int rc;
2688
2689 if (!(sbsec->flags & SE_SBINITIALIZED))
2690 return 0;
2691
2692 if (!opts)
2693 return 0;
2694
2695 if (opts->fscontext) {
2696 rc = parse_sid(sb, opts->fscontext, &sid);
2697 if (rc)
2698 return rc;
2699 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2700 goto out_bad_option;
2701 }
2702 if (opts->context) {
2703 rc = parse_sid(sb, opts->context, &sid);
2704 if (rc)
2705 return rc;
2706 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2707 goto out_bad_option;
2708 }
2709 if (opts->rootcontext) {
2710 struct inode_security_struct *root_isec;
2711 root_isec = backing_inode_security(sb->s_root);
2712 rc = parse_sid(sb, opts->rootcontext, &sid);
2713 if (rc)
2714 return rc;
2715 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2716 goto out_bad_option;
2717 }
2718 if (opts->defcontext) {
2719 rc = parse_sid(sb, opts->defcontext, &sid);
2720 if (rc)
2721 return rc;
2722 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2723 goto out_bad_option;
2724 }
2725 return 0;
2726
2727out_bad_option:
2728 pr_warn("SELinux: unable to change security options "
2729 "during remount (dev %s, type=%s)\n", sb->s_id,
2730 sb->s_type->name);
2731 return -EINVAL;
2732}
2733
2734static int selinux_sb_kern_mount(struct super_block *sb)
2735{
2736 const struct cred *cred = current_cred();
2737 struct common_audit_data ad;
2738
2739 ad.type = LSM_AUDIT_DATA_DENTRY;
2740 ad.u.dentry = sb->s_root;
2741 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2742}
2743
2744static int selinux_sb_statfs(struct dentry *dentry)
2745{
2746 const struct cred *cred = current_cred();
2747 struct common_audit_data ad;
2748
2749 ad.type = LSM_AUDIT_DATA_DENTRY;
2750 ad.u.dentry = dentry->d_sb->s_root;
2751 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2752}
2753
2754static int selinux_mount(const char *dev_name,
2755 const struct path *path,
2756 const char *type,
2757 unsigned long flags,
2758 void *data)
2759{
2760 const struct cred *cred = current_cred();
2761
2762 if (flags & MS_REMOUNT)
2763 return superblock_has_perm(cred, path->dentry->d_sb,
2764 FILESYSTEM__REMOUNT, NULL);
2765 else
2766 return path_has_perm(cred, path, FILE__MOUNTON);
2767}
2768
2769static int selinux_umount(struct vfsmount *mnt, int flags)
2770{
2771 const struct cred *cred = current_cred();
2772
2773 return superblock_has_perm(cred, mnt->mnt_sb,
2774 FILESYSTEM__UNMOUNT, NULL);
2775}
2776
2777static int selinux_fs_context_dup(struct fs_context *fc,
2778 struct fs_context *src_fc)
2779{
2780 const struct selinux_mnt_opts *src = src_fc->security;
2781 struct selinux_mnt_opts *opts;
2782
2783 if (!src)
2784 return 0;
2785
2786 fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
2787 if (!fc->security)
2788 return -ENOMEM;
2789
2790 opts = fc->security;
2791
2792 if (src->fscontext) {
2793 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL);
2794 if (!opts->fscontext)
2795 return -ENOMEM;
2796 }
2797 if (src->context) {
2798 opts->context = kstrdup(src->context, GFP_KERNEL);
2799 if (!opts->context)
2800 return -ENOMEM;
2801 }
2802 if (src->rootcontext) {
2803 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL);
2804 if (!opts->rootcontext)
2805 return -ENOMEM;
2806 }
2807 if (src->defcontext) {
2808 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL);
2809 if (!opts->defcontext)
2810 return -ENOMEM;
2811 }
2812 return 0;
2813}
2814
2815static const struct fs_parameter_spec selinux_param_specs[] = {
2816 fsparam_string(CONTEXT_STR, Opt_context),
2817 fsparam_string(DEFCONTEXT_STR, Opt_defcontext),
2818 fsparam_string(FSCONTEXT_STR, Opt_fscontext),
2819 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2820 fsparam_flag (SECLABEL_STR, Opt_seclabel),
2821 {}
2822};
2823
2824static const struct fs_parameter_description selinux_fs_parameters = {
2825 .name = "SELinux",
2826 .specs = selinux_param_specs,
2827};
2828
2829static int selinux_fs_context_parse_param(struct fs_context *fc,
2830 struct fs_parameter *param)
2831{
2832 struct fs_parse_result result;
2833 int opt, rc;
2834
2835 opt = fs_parse(fc, &selinux_fs_parameters, param, &result);
2836 if (opt < 0)
2837 return opt;
2838
2839 rc = selinux_add_opt(opt, param->string, &fc->security);
2840 if (!rc) {
2841 param->string = NULL;
2842 rc = 1;
2843 }
2844 return rc;
2845}
2846
2847/* inode security operations */
2848
2849static int selinux_inode_alloc_security(struct inode *inode)
2850{
2851 return inode_alloc_security(inode);
2852}
2853
2854static void selinux_inode_free_security(struct inode *inode)
2855{
2856 inode_free_security(inode);
2857}
2858
2859static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2860 const struct qstr *name, void **ctx,
2861 u32 *ctxlen)
2862{
2863 u32 newsid;
2864 int rc;
2865
2866 rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2867 d_inode(dentry->d_parent), name,
2868 inode_mode_to_security_class(mode),
2869 &newsid);
2870 if (rc)
2871 return rc;
2872
2873 return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2874 ctxlen);
2875}
2876
2877static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2878 struct qstr *name,
2879 const struct cred *old,
2880 struct cred *new)
2881{
2882 u32 newsid;
2883 int rc;
2884 struct task_security_struct *tsec;
2885
2886 rc = selinux_determine_inode_label(selinux_cred(old),
2887 d_inode(dentry->d_parent), name,
2888 inode_mode_to_security_class(mode),
2889 &newsid);
2890 if (rc)
2891 return rc;
2892
2893 tsec = selinux_cred(new);
2894 tsec->create_sid = newsid;
2895 return 0;
2896}
2897
2898static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2899 const struct qstr *qstr,
2900 const char **name,
2901 void **value, size_t *len)
2902{
2903 const struct task_security_struct *tsec = selinux_cred(current_cred());
2904 struct superblock_security_struct *sbsec;
2905 u32 newsid, clen;
2906 int rc;
2907 char *context;
2908
2909 sbsec = dir->i_sb->s_security;
2910
2911 newsid = tsec->create_sid;
2912
2913 rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2914 dir, qstr,
2915 inode_mode_to_security_class(inode->i_mode),
2916 &newsid);
2917 if (rc)
2918 return rc;
2919
2920 /* Possibly defer initialization to selinux_complete_init. */
2921 if (sbsec->flags & SE_SBINITIALIZED) {
2922 struct inode_security_struct *isec = selinux_inode(inode);
2923 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2924 isec->sid = newsid;
2925 isec->initialized = LABEL_INITIALIZED;
2926 }
2927
2928 if (!selinux_state.initialized || !(sbsec->flags & SBLABEL_MNT))
2929 return -EOPNOTSUPP;
2930
2931 if (name)
2932 *name = XATTR_SELINUX_SUFFIX;
2933
2934 if (value && len) {
2935 rc = security_sid_to_context_force(&selinux_state, newsid,
2936 &context, &clen);
2937 if (rc)
2938 return rc;
2939 *value = context;
2940 *len = clen;
2941 }
2942
2943 return 0;
2944}
2945
2946static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2947{
2948 return may_create(dir, dentry, SECCLASS_FILE);
2949}
2950
2951static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2952{
2953 return may_link(dir, old_dentry, MAY_LINK);
2954}
2955
2956static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2957{
2958 return may_link(dir, dentry, MAY_UNLINK);
2959}
2960
2961static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2962{
2963 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2964}
2965
2966static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2967{
2968 return may_create(dir, dentry, SECCLASS_DIR);
2969}
2970
2971static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2972{
2973 return may_link(dir, dentry, MAY_RMDIR);
2974}
2975
2976static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2977{
2978 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2979}
2980
2981static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2982 struct inode *new_inode, struct dentry *new_dentry)
2983{
2984 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2985}
2986
2987static int selinux_inode_readlink(struct dentry *dentry)
2988{
2989 const struct cred *cred = current_cred();
2990
2991 return dentry_has_perm(cred, dentry, FILE__READ);
2992}
2993
2994static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2995 bool rcu)
2996{
2997 const struct cred *cred = current_cred();
2998 struct common_audit_data ad;
2999 struct inode_security_struct *isec;
3000 u32 sid;
3001
3002 validate_creds(cred);
3003
3004 ad.type = LSM_AUDIT_DATA_DENTRY;
3005 ad.u.dentry = dentry;
3006 sid = cred_sid(cred);
3007 isec = inode_security_rcu(inode, rcu);
3008 if (IS_ERR(isec))
3009 return PTR_ERR(isec);
3010
3011 return avc_has_perm(&selinux_state,
3012 sid, isec->sid, isec->sclass, FILE__READ, &ad);
3013}
3014
3015static noinline int audit_inode_permission(struct inode *inode,
3016 u32 perms, u32 audited, u32 denied,
3017 int result,
3018 unsigned flags)
3019{
3020 struct common_audit_data ad;
3021 struct inode_security_struct *isec = selinux_inode(inode);
3022 int rc;
3023
3024 ad.type = LSM_AUDIT_DATA_INODE;
3025 ad.u.inode = inode;
3026
3027 rc = slow_avc_audit(&selinux_state,
3028 current_sid(), isec->sid, isec->sclass, perms,
3029 audited, denied, result, &ad, flags);
3030 if (rc)
3031 return rc;
3032 return 0;
3033}
3034
3035static int selinux_inode_permission(struct inode *inode, int mask)
3036{
3037 const struct cred *cred = current_cred();
3038 u32 perms;
3039 bool from_access;
3040 unsigned flags = mask & MAY_NOT_BLOCK;
3041 struct inode_security_struct *isec;
3042 u32 sid;
3043 struct av_decision avd;
3044 int rc, rc2;
3045 u32 audited, denied;
3046
3047 from_access = mask & MAY_ACCESS;
3048 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3049
3050 /* No permission to check. Existence test. */
3051 if (!mask)
3052 return 0;
3053
3054 validate_creds(cred);
3055
3056 if (unlikely(IS_PRIVATE(inode)))
3057 return 0;
3058
3059 perms = file_mask_to_av(inode->i_mode, mask);
3060
3061 sid = cred_sid(cred);
3062 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
3063 if (IS_ERR(isec))
3064 return PTR_ERR(isec);
3065
3066 rc = avc_has_perm_noaudit(&selinux_state,
3067 sid, isec->sid, isec->sclass, perms,
3068 (flags & MAY_NOT_BLOCK) ? AVC_NONBLOCKING : 0,
3069 &avd);
3070 audited = avc_audit_required(perms, &avd, rc,
3071 from_access ? FILE__AUDIT_ACCESS : 0,
3072 &denied);
3073 if (likely(!audited))
3074 return rc;
3075
3076 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3077 if (rc2)
3078 return rc2;
3079 return rc;
3080}
3081
3082static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3083{
3084 const struct cred *cred = current_cred();
3085 struct inode *inode = d_backing_inode(dentry);
3086 unsigned int ia_valid = iattr->ia_valid;
3087 __u32 av = FILE__WRITE;
3088
3089 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3090 if (ia_valid & ATTR_FORCE) {
3091 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3092 ATTR_FORCE);
3093 if (!ia_valid)
3094 return 0;
3095 }
3096
3097 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3098 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3099 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3100
3101 if (selinux_policycap_openperm() &&
3102 inode->i_sb->s_magic != SOCKFS_MAGIC &&
3103 (ia_valid & ATTR_SIZE) &&
3104 !(ia_valid & ATTR_FILE))
3105 av |= FILE__OPEN;
3106
3107 return dentry_has_perm(cred, dentry, av);
3108}
3109
3110static int selinux_inode_getattr(const struct path *path)
3111{
3112 return path_has_perm(current_cred(), path, FILE__GETATTR);
3113}
3114
3115static bool has_cap_mac_admin(bool audit)
3116{
3117 const struct cred *cred = current_cred();
3118 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3119
3120 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3121 return false;
3122 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3123 return false;
3124 return true;
3125}
3126
3127static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3128 const void *value, size_t size, int flags)
3129{
3130 struct inode *inode = d_backing_inode(dentry);
3131 struct inode_security_struct *isec;
3132 struct superblock_security_struct *sbsec;
3133 struct common_audit_data ad;
3134 u32 newsid, sid = current_sid();
3135 int rc = 0;
3136
3137 if (strcmp(name, XATTR_NAME_SELINUX)) {
3138 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3139 if (rc)
3140 return rc;
3141
3142 /* Not an attribute we recognize, so just check the
3143 ordinary setattr permission. */
3144 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3145 }
3146
3147 sbsec = inode->i_sb->s_security;
3148 if (!(sbsec->flags & SBLABEL_MNT))
3149 return -EOPNOTSUPP;
3150
3151 if (!inode_owner_or_capable(inode))
3152 return -EPERM;
3153
3154 ad.type = LSM_AUDIT_DATA_DENTRY;
3155 ad.u.dentry = dentry;
3156
3157 isec = backing_inode_security(dentry);
3158 rc = avc_has_perm(&selinux_state,
3159 sid, isec->sid, isec->sclass,
3160 FILE__RELABELFROM, &ad);
3161 if (rc)
3162 return rc;
3163
3164 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3165 GFP_KERNEL);
3166 if (rc == -EINVAL) {
3167 if (!has_cap_mac_admin(true)) {
3168 struct audit_buffer *ab;
3169 size_t audit_size;
3170
3171 /* We strip a nul only if it is at the end, otherwise the
3172 * context contains a nul and we should audit that */
3173 if (value) {
3174 const char *str = value;
3175
3176 if (str[size - 1] == '\0')
3177 audit_size = size - 1;
3178 else
3179 audit_size = size;
3180 } else {
3181 audit_size = 0;
3182 }
3183 ab = audit_log_start(audit_context(),
3184 GFP_ATOMIC, AUDIT_SELINUX_ERR);
3185 audit_log_format(ab, "op=setxattr invalid_context=");
3186 audit_log_n_untrustedstring(ab, value, audit_size);
3187 audit_log_end(ab);
3188
3189 return rc;
3190 }
3191 rc = security_context_to_sid_force(&selinux_state, value,
3192 size, &newsid);
3193 }
3194 if (rc)
3195 return rc;
3196
3197 rc = avc_has_perm(&selinux_state,
3198 sid, newsid, isec->sclass,
3199 FILE__RELABELTO, &ad);
3200 if (rc)
3201 return rc;
3202
3203 rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3204 sid, isec->sclass);
3205 if (rc)
3206 return rc;
3207
3208 return avc_has_perm(&selinux_state,
3209 newsid,
3210 sbsec->sid,
3211 SECCLASS_FILESYSTEM,
3212 FILESYSTEM__ASSOCIATE,
3213 &ad);
3214}
3215
3216static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3217 const void *value, size_t size,
3218 int flags)
3219{
3220 struct inode *inode = d_backing_inode(dentry);
3221 struct inode_security_struct *isec;
3222 u32 newsid;
3223 int rc;
3224
3225 if (strcmp(name, XATTR_NAME_SELINUX)) {
3226 /* Not an attribute we recognize, so nothing to do. */
3227 return;
3228 }
3229
3230 rc = security_context_to_sid_force(&selinux_state, value, size,
3231 &newsid);
3232 if (rc) {
3233 pr_err("SELinux: unable to map context to SID"
3234 "for (%s, %lu), rc=%d\n",
3235 inode->i_sb->s_id, inode->i_ino, -rc);
3236 return;
3237 }
3238
3239 isec = backing_inode_security(dentry);
3240 spin_lock(&isec->lock);
3241 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3242 isec->sid = newsid;
3243 isec->initialized = LABEL_INITIALIZED;
3244 spin_unlock(&isec->lock);
3245
3246 return;
3247}
3248
3249static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3250{
3251 const struct cred *cred = current_cred();
3252
3253 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3254}
3255
3256static int selinux_inode_listxattr(struct dentry *dentry)
3257{
3258 const struct cred *cred = current_cred();
3259
3260 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3261}
3262
3263static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3264{
3265 if (strcmp(name, XATTR_NAME_SELINUX)) {
3266 int rc = cap_inode_removexattr(dentry, name);
3267 if (rc)
3268 return rc;
3269
3270 /* Not an attribute we recognize, so just check the
3271 ordinary setattr permission. */
3272 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3273 }
3274
3275 /* No one is allowed to remove a SELinux security label.
3276 You can change the label, but all data must be labeled. */
3277 return -EACCES;
3278}
3279
3280static int selinux_path_notify(const struct path *path, u64 mask,
3281 unsigned int obj_type)
3282{
3283 int ret;
3284 u32 perm;
3285
3286 struct common_audit_data ad;
3287
3288 ad.type = LSM_AUDIT_DATA_PATH;
3289 ad.u.path = *path;
3290
3291 /*
3292 * Set permission needed based on the type of mark being set.
3293 * Performs an additional check for sb watches.
3294 */
3295 switch (obj_type) {
3296 case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3297 perm = FILE__WATCH_MOUNT;
3298 break;
3299 case FSNOTIFY_OBJ_TYPE_SB:
3300 perm = FILE__WATCH_SB;
3301 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3302 FILESYSTEM__WATCH, &ad);
3303 if (ret)
3304 return ret;
3305 break;
3306 case FSNOTIFY_OBJ_TYPE_INODE:
3307 perm = FILE__WATCH;
3308 break;
3309 default:
3310 return -EINVAL;
3311 }
3312
3313 /* blocking watches require the file:watch_with_perm permission */
3314 if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3315 perm |= FILE__WATCH_WITH_PERM;
3316
3317 /* watches on read-like events need the file:watch_reads permission */
3318 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3319 perm |= FILE__WATCH_READS;
3320
3321 return path_has_perm(current_cred(), path, perm);
3322}
3323
3324/*
3325 * Copy the inode security context value to the user.
3326 *
3327 * Permission check is handled by selinux_inode_getxattr hook.
3328 */
3329static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3330{
3331 u32 size;
3332 int error;
3333 char *context = NULL;
3334 struct inode_security_struct *isec;
3335
3336 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3337 return -EOPNOTSUPP;
3338
3339 /*
3340 * If the caller has CAP_MAC_ADMIN, then get the raw context
3341 * value even if it is not defined by current policy; otherwise,
3342 * use the in-core value under current policy.
3343 * Use the non-auditing forms of the permission checks since
3344 * getxattr may be called by unprivileged processes commonly
3345 * and lack of permission just means that we fall back to the
3346 * in-core context value, not a denial.
3347 */
3348 isec = inode_security(inode);
3349 if (has_cap_mac_admin(false))
3350 error = security_sid_to_context_force(&selinux_state,
3351 isec->sid, &context,
3352 &size);
3353 else
3354 error = security_sid_to_context(&selinux_state, isec->sid,
3355 &context, &size);
3356 if (error)
3357 return error;
3358 error = size;
3359 if (alloc) {
3360 *buffer = context;
3361 goto out_nofree;
3362 }
3363 kfree(context);
3364out_nofree:
3365 return error;
3366}
3367
3368static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3369 const void *value, size_t size, int flags)
3370{
3371 struct inode_security_struct *isec = inode_security_novalidate(inode);
3372 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
3373 u32 newsid;
3374 int rc;
3375
3376 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3377 return -EOPNOTSUPP;
3378
3379 if (!(sbsec->flags & SBLABEL_MNT))
3380 return -EOPNOTSUPP;
3381
3382 if (!value || !size)
3383 return -EACCES;
3384
3385 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3386 GFP_KERNEL);
3387 if (rc)
3388 return rc;
3389
3390 spin_lock(&isec->lock);
3391 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3392 isec->sid = newsid;
3393 isec->initialized = LABEL_INITIALIZED;
3394 spin_unlock(&isec->lock);
3395 return 0;
3396}
3397
3398static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3399{
3400 const int len = sizeof(XATTR_NAME_SELINUX);
3401 if (buffer && len <= buffer_size)
3402 memcpy(buffer, XATTR_NAME_SELINUX, len);
3403 return len;
3404}
3405
3406static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3407{
3408 struct inode_security_struct *isec = inode_security_novalidate(inode);
3409 *secid = isec->sid;
3410}
3411
3412static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3413{
3414 u32 sid;
3415 struct task_security_struct *tsec;
3416 struct cred *new_creds = *new;
3417
3418 if (new_creds == NULL) {
3419 new_creds = prepare_creds();
3420 if (!new_creds)
3421 return -ENOMEM;
3422 }
3423
3424 tsec = selinux_cred(new_creds);
3425 /* Get label from overlay inode and set it in create_sid */
3426 selinux_inode_getsecid(d_inode(src), &sid);
3427 tsec->create_sid = sid;
3428 *new = new_creds;
3429 return 0;
3430}
3431
3432static int selinux_inode_copy_up_xattr(const char *name)
3433{
3434 /* The copy_up hook above sets the initial context on an inode, but we
3435 * don't then want to overwrite it by blindly copying all the lower
3436 * xattrs up. Instead, we have to filter out SELinux-related xattrs.
3437 */
3438 if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3439 return 1; /* Discard */
3440 /*
3441 * Any other attribute apart from SELINUX is not claimed, supported
3442 * by selinux.
3443 */
3444 return -EOPNOTSUPP;
3445}
3446
3447/* kernfs node operations */
3448
3449static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3450 struct kernfs_node *kn)
3451{
3452 const struct task_security_struct *tsec = selinux_cred(current_cred());
3453 u32 parent_sid, newsid, clen;
3454 int rc;
3455 char *context;
3456
3457 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3458 if (rc == -ENODATA)
3459 return 0;
3460 else if (rc < 0)
3461 return rc;
3462
3463 clen = (u32)rc;
3464 context = kmalloc(clen, GFP_KERNEL);
3465 if (!context)
3466 return -ENOMEM;
3467
3468 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3469 if (rc < 0) {
3470 kfree(context);
3471 return rc;
3472 }
3473
3474 rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
3475 GFP_KERNEL);
3476 kfree(context);
3477 if (rc)
3478 return rc;
3479
3480 if (tsec->create_sid) {
3481 newsid = tsec->create_sid;
3482 } else {
3483 u16 secclass = inode_mode_to_security_class(kn->mode);
3484 struct qstr q;
3485
3486 q.name = kn->name;
3487 q.hash_len = hashlen_string(kn_dir, kn->name);
3488
3489 rc = security_transition_sid(&selinux_state, tsec->sid,
3490 parent_sid, secclass, &q,
3491 &newsid);
3492 if (rc)
3493 return rc;
3494 }
3495
3496 rc = security_sid_to_context_force(&selinux_state, newsid,
3497 &context, &clen);
3498 if (rc)
3499 return rc;
3500
3501 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3502 XATTR_CREATE);
3503 kfree(context);
3504 return rc;
3505}
3506
3507
3508/* file security operations */
3509
3510static int selinux_revalidate_file_permission(struct file *file, int mask)
3511{
3512 const struct cred *cred = current_cred();
3513 struct inode *inode = file_inode(file);
3514
3515 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3516 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3517 mask |= MAY_APPEND;
3518
3519 return file_has_perm(cred, file,
3520 file_mask_to_av(inode->i_mode, mask));
3521}
3522
3523static int selinux_file_permission(struct file *file, int mask)
3524{
3525 struct inode *inode = file_inode(file);
3526 struct file_security_struct *fsec = selinux_file(file);
3527 struct inode_security_struct *isec;
3528 u32 sid = current_sid();
3529
3530 if (!mask)
3531 /* No permission to check. Existence test. */
3532 return 0;
3533
3534 isec = inode_security(inode);
3535 if (sid == fsec->sid && fsec->isid == isec->sid &&
3536 fsec->pseqno == avc_policy_seqno(&selinux_state))
3537 /* No change since file_open check. */
3538 return 0;
3539
3540 return selinux_revalidate_file_permission(file, mask);
3541}
3542
3543static int selinux_file_alloc_security(struct file *file)
3544{
3545 return file_alloc_security(file);
3546}
3547
3548/*
3549 * Check whether a task has the ioctl permission and cmd
3550 * operation to an inode.
3551 */
3552static int ioctl_has_perm(const struct cred *cred, struct file *file,
3553 u32 requested, u16 cmd)
3554{
3555 struct common_audit_data ad;
3556 struct file_security_struct *fsec = selinux_file(file);
3557 struct inode *inode = file_inode(file);
3558 struct inode_security_struct *isec;
3559 struct lsm_ioctlop_audit ioctl;
3560 u32 ssid = cred_sid(cred);
3561 int rc;
3562 u8 driver = cmd >> 8;
3563 u8 xperm = cmd & 0xff;
3564
3565 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3566 ad.u.op = &ioctl;
3567 ad.u.op->cmd = cmd;
3568 ad.u.op->path = file->f_path;
3569
3570 if (ssid != fsec->sid) {
3571 rc = avc_has_perm(&selinux_state,
3572 ssid, fsec->sid,
3573 SECCLASS_FD,
3574 FD__USE,
3575 &ad);
3576 if (rc)
3577 goto out;
3578 }
3579
3580 if (unlikely(IS_PRIVATE(inode)))
3581 return 0;
3582
3583 isec = inode_security(inode);
3584 rc = avc_has_extended_perms(&selinux_state,
3585 ssid, isec->sid, isec->sclass,
3586 requested, driver, xperm, &ad);
3587out:
3588 return rc;
3589}
3590
3591static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3592 unsigned long arg)
3593{
3594 const struct cred *cred = current_cred();
3595 int error = 0;
3596
3597 switch (cmd) {
3598 case FIONREAD:
3599 /* fall through */
3600 case FIBMAP:
3601 /* fall through */
3602 case FIGETBSZ:
3603 /* fall through */
3604 case FS_IOC_GETFLAGS:
3605 /* fall through */
3606 case FS_IOC_GETVERSION:
3607 error = file_has_perm(cred, file, FILE__GETATTR);
3608 break;
3609
3610 case FS_IOC_SETFLAGS:
3611 /* fall through */
3612 case FS_IOC_SETVERSION:
3613 error = file_has_perm(cred, file, FILE__SETATTR);
3614 break;
3615
3616 /* sys_ioctl() checks */
3617 case FIONBIO:
3618 /* fall through */
3619 case FIOASYNC:
3620 error = file_has_perm(cred, file, 0);
3621 break;
3622
3623 case KDSKBENT:
3624 case KDSKBSENT:
3625 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3626 CAP_OPT_NONE, true);
3627 break;
3628
3629 /* default case assumes that the command will go
3630 * to the file's ioctl() function.
3631 */
3632 default:
3633 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3634 }
3635 return error;
3636}
3637
3638static int default_noexec;
3639
3640static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3641{
3642 const struct cred *cred = current_cred();
3643 u32 sid = cred_sid(cred);
3644 int rc = 0;
3645
3646 if (default_noexec &&
3647 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3648 (!shared && (prot & PROT_WRITE)))) {
3649 /*
3650 * We are making executable an anonymous mapping or a
3651 * private file mapping that will also be writable.
3652 * This has an additional check.
3653 */
3654 rc = avc_has_perm(&selinux_state,
3655 sid, sid, SECCLASS_PROCESS,
3656 PROCESS__EXECMEM, NULL);
3657 if (rc)
3658 goto error;
3659 }
3660
3661 if (file) {
3662 /* read access is always possible with a mapping */
3663 u32 av = FILE__READ;
3664
3665 /* write access only matters if the mapping is shared */
3666 if (shared && (prot & PROT_WRITE))
3667 av |= FILE__WRITE;
3668
3669 if (prot & PROT_EXEC)
3670 av |= FILE__EXECUTE;
3671
3672 return file_has_perm(cred, file, av);
3673 }
3674
3675error:
3676 return rc;
3677}
3678
3679static int selinux_mmap_addr(unsigned long addr)
3680{
3681 int rc = 0;
3682
3683 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3684 u32 sid = current_sid();
3685 rc = avc_has_perm(&selinux_state,
3686 sid, sid, SECCLASS_MEMPROTECT,
3687 MEMPROTECT__MMAP_ZERO, NULL);
3688 }
3689
3690 return rc;
3691}
3692
3693static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3694 unsigned long prot, unsigned long flags)
3695{
3696 struct common_audit_data ad;
3697 int rc;
3698
3699 if (file) {
3700 ad.type = LSM_AUDIT_DATA_FILE;
3701 ad.u.file = file;
3702 rc = inode_has_perm(current_cred(), file_inode(file),
3703 FILE__MAP, &ad);
3704 if (rc)
3705 return rc;
3706 }
3707
3708 if (selinux_state.checkreqprot)
3709 prot = reqprot;
3710
3711 return file_map_prot_check(file, prot,
3712 (flags & MAP_TYPE) == MAP_SHARED);
3713}
3714
3715static int selinux_file_mprotect(struct vm_area_struct *vma,
3716 unsigned long reqprot,
3717 unsigned long prot)
3718{
3719 const struct cred *cred = current_cred();
3720 u32 sid = cred_sid(cred);
3721
3722 if (selinux_state.checkreqprot)
3723 prot = reqprot;
3724
3725 if (default_noexec &&
3726 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3727 int rc = 0;
3728 if (vma->vm_start >= vma->vm_mm->start_brk &&
3729 vma->vm_end <= vma->vm_mm->brk) {
3730 rc = avc_has_perm(&selinux_state,
3731 sid, sid, SECCLASS_PROCESS,
3732 PROCESS__EXECHEAP, NULL);
3733 } else if (!vma->vm_file &&
3734 ((vma->vm_start <= vma->vm_mm->start_stack &&
3735 vma->vm_end >= vma->vm_mm->start_stack) ||
3736 vma_is_stack_for_current(vma))) {
3737 rc = avc_has_perm(&selinux_state,
3738 sid, sid, SECCLASS_PROCESS,
3739 PROCESS__EXECSTACK, NULL);
3740 } else if (vma->vm_file && vma->anon_vma) {
3741 /*
3742 * We are making executable a file mapping that has
3743 * had some COW done. Since pages might have been
3744 * written, check ability to execute the possibly
3745 * modified content. This typically should only
3746 * occur for text relocations.
3747 */
3748 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3749 }
3750 if (rc)
3751 return rc;
3752 }
3753
3754 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3755}
3756
3757static int selinux_file_lock(struct file *file, unsigned int cmd)
3758{
3759 const struct cred *cred = current_cred();
3760
3761 return file_has_perm(cred, file, FILE__LOCK);
3762}
3763
3764static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3765 unsigned long arg)
3766{
3767 const struct cred *cred = current_cred();
3768 int err = 0;
3769
3770 switch (cmd) {
3771 case F_SETFL:
3772 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3773 err = file_has_perm(cred, file, FILE__WRITE);
3774 break;
3775 }
3776 /* fall through */
3777 case F_SETOWN:
3778 case F_SETSIG:
3779 case F_GETFL:
3780 case F_GETOWN:
3781 case F_GETSIG:
3782 case F_GETOWNER_UIDS:
3783 /* Just check FD__USE permission */
3784 err = file_has_perm(cred, file, 0);
3785 break;
3786 case F_GETLK:
3787 case F_SETLK:
3788 case F_SETLKW:
3789 case F_OFD_GETLK:
3790 case F_OFD_SETLK:
3791 case F_OFD_SETLKW:
3792#if BITS_PER_LONG == 32
3793 case F_GETLK64:
3794 case F_SETLK64:
3795 case F_SETLKW64:
3796#endif
3797 err = file_has_perm(cred, file, FILE__LOCK);
3798 break;
3799 }
3800
3801 return err;
3802}
3803
3804static void selinux_file_set_fowner(struct file *file)
3805{
3806 struct file_security_struct *fsec;
3807
3808 fsec = selinux_file(file);
3809 fsec->fown_sid = current_sid();
3810}
3811
3812static int selinux_file_send_sigiotask(struct task_struct *tsk,
3813 struct fown_struct *fown, int signum)
3814{
3815 struct file *file;
3816 u32 sid = task_sid(tsk);
3817 u32 perm;
3818 struct file_security_struct *fsec;
3819
3820 /* struct fown_struct is never outside the context of a struct file */
3821 file = container_of(fown, struct file, f_owner);
3822
3823 fsec = selinux_file(file);
3824
3825 if (!signum)
3826 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3827 else
3828 perm = signal_to_av(signum);
3829
3830 return avc_has_perm(&selinux_state,
3831 fsec->fown_sid, sid,
3832 SECCLASS_PROCESS, perm, NULL);
3833}
3834
3835static int selinux_file_receive(struct file *file)
3836{
3837 const struct cred *cred = current_cred();
3838
3839 return file_has_perm(cred, file, file_to_av(file));
3840}
3841
3842static int selinux_file_open(struct file *file)
3843{
3844 struct file_security_struct *fsec;
3845 struct inode_security_struct *isec;
3846
3847 fsec = selinux_file(file);
3848 isec = inode_security(file_inode(file));
3849 /*
3850 * Save inode label and policy sequence number
3851 * at open-time so that selinux_file_permission
3852 * can determine whether revalidation is necessary.
3853 * Task label is already saved in the file security
3854 * struct as its SID.
3855 */
3856 fsec->isid = isec->sid;
3857 fsec->pseqno = avc_policy_seqno(&selinux_state);
3858 /*
3859 * Since the inode label or policy seqno may have changed
3860 * between the selinux_inode_permission check and the saving
3861 * of state above, recheck that access is still permitted.
3862 * Otherwise, access might never be revalidated against the
3863 * new inode label or new policy.
3864 * This check is not redundant - do not remove.
3865 */
3866 return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3867}
3868
3869/* task security operations */
3870
3871static int selinux_task_alloc(struct task_struct *task,
3872 unsigned long clone_flags)
3873{
3874 u32 sid = current_sid();
3875
3876 return avc_has_perm(&selinux_state,
3877 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3878}
3879
3880/*
3881 * prepare a new set of credentials for modification
3882 */
3883static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3884 gfp_t gfp)
3885{
3886 const struct task_security_struct *old_tsec = selinux_cred(old);
3887 struct task_security_struct *tsec = selinux_cred(new);
3888
3889 *tsec = *old_tsec;
3890 return 0;
3891}
3892
3893/*
3894 * transfer the SELinux data to a blank set of creds
3895 */
3896static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3897{
3898 const struct task_security_struct *old_tsec = selinux_cred(old);
3899 struct task_security_struct *tsec = selinux_cred(new);
3900
3901 *tsec = *old_tsec;
3902}
3903
3904static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3905{
3906 *secid = cred_sid(c);
3907}
3908
3909/*
3910 * set the security data for a kernel service
3911 * - all the creation contexts are set to unlabelled
3912 */
3913static int selinux_kernel_act_as(struct cred *new, u32 secid)
3914{
3915 struct task_security_struct *tsec = selinux_cred(new);
3916 u32 sid = current_sid();
3917 int ret;
3918
3919 ret = avc_has_perm(&selinux_state,
3920 sid, secid,
3921 SECCLASS_KERNEL_SERVICE,
3922 KERNEL_SERVICE__USE_AS_OVERRIDE,
3923 NULL);
3924 if (ret == 0) {
3925 tsec->sid = secid;
3926 tsec->create_sid = 0;
3927 tsec->keycreate_sid = 0;
3928 tsec->sockcreate_sid = 0;
3929 }
3930 return ret;
3931}
3932
3933/*
3934 * set the file creation context in a security record to the same as the
3935 * objective context of the specified inode
3936 */
3937static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3938{
3939 struct inode_security_struct *isec = inode_security(inode);
3940 struct task_security_struct *tsec = selinux_cred(new);
3941 u32 sid = current_sid();
3942 int ret;
3943
3944 ret = avc_has_perm(&selinux_state,
3945 sid, isec->sid,
3946 SECCLASS_KERNEL_SERVICE,
3947 KERNEL_SERVICE__CREATE_FILES_AS,
3948 NULL);
3949
3950 if (ret == 0)
3951 tsec->create_sid = isec->sid;
3952 return ret;
3953}
3954
3955static int selinux_kernel_module_request(char *kmod_name)
3956{
3957 struct common_audit_data ad;
3958
3959 ad.type = LSM_AUDIT_DATA_KMOD;
3960 ad.u.kmod_name = kmod_name;
3961
3962 return avc_has_perm(&selinux_state,
3963 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3964 SYSTEM__MODULE_REQUEST, &ad);
3965}
3966
3967static int selinux_kernel_module_from_file(struct file *file)
3968{
3969 struct common_audit_data ad;
3970 struct inode_security_struct *isec;
3971 struct file_security_struct *fsec;
3972 u32 sid = current_sid();
3973 int rc;
3974
3975 /* init_module */
3976 if (file == NULL)
3977 return avc_has_perm(&selinux_state,
3978 sid, sid, SECCLASS_SYSTEM,
3979 SYSTEM__MODULE_LOAD, NULL);
3980
3981 /* finit_module */
3982
3983 ad.type = LSM_AUDIT_DATA_FILE;
3984 ad.u.file = file;
3985
3986 fsec = selinux_file(file);
3987 if (sid != fsec->sid) {
3988 rc = avc_has_perm(&selinux_state,
3989 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3990 if (rc)
3991 return rc;
3992 }
3993
3994 isec = inode_security(file_inode(file));
3995 return avc_has_perm(&selinux_state,
3996 sid, isec->sid, SECCLASS_SYSTEM,
3997 SYSTEM__MODULE_LOAD, &ad);
3998}
3999
4000static int selinux_kernel_read_file(struct file *file,
4001 enum kernel_read_file_id id)
4002{
4003 int rc = 0;
4004
4005 switch (id) {
4006 case READING_MODULE:
4007 rc = selinux_kernel_module_from_file(file);
4008 break;
4009 default:
4010 break;
4011 }
4012
4013 return rc;
4014}
4015
4016static int selinux_kernel_load_data(enum kernel_load_data_id id)
4017{
4018 int rc = 0;
4019
4020 switch (id) {
4021 case LOADING_MODULE:
4022 rc = selinux_kernel_module_from_file(NULL);
4023 default:
4024 break;
4025 }
4026
4027 return rc;
4028}
4029
4030static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4031{
4032 return avc_has_perm(&selinux_state,
4033 current_sid(), task_sid(p), SECCLASS_PROCESS,
4034 PROCESS__SETPGID, NULL);
4035}
4036
4037static int selinux_task_getpgid(struct task_struct *p)
4038{
4039 return avc_has_perm(&selinux_state,
4040 current_sid(), task_sid(p), SECCLASS_PROCESS,
4041 PROCESS__GETPGID, NULL);
4042}
4043
4044static int selinux_task_getsid(struct task_struct *p)
4045{
4046 return avc_has_perm(&selinux_state,
4047 current_sid(), task_sid(p), SECCLASS_PROCESS,
4048 PROCESS__GETSESSION, NULL);
4049}
4050
4051static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4052{
4053 *secid = task_sid(p);
4054}
4055
4056static int selinux_task_setnice(struct task_struct *p, int nice)
4057{
4058 return avc_has_perm(&selinux_state,
4059 current_sid(), task_sid(p), SECCLASS_PROCESS,
4060 PROCESS__SETSCHED, NULL);
4061}
4062
4063static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4064{
4065 return avc_has_perm(&selinux_state,
4066 current_sid(), task_sid(p), SECCLASS_PROCESS,
4067 PROCESS__SETSCHED, NULL);
4068}
4069
4070static int selinux_task_getioprio(struct task_struct *p)
4071{
4072 return avc_has_perm(&selinux_state,
4073 current_sid(), task_sid(p), SECCLASS_PROCESS,
4074 PROCESS__GETSCHED, NULL);
4075}
4076
4077static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4078 unsigned int flags)
4079{
4080 u32 av = 0;
4081
4082 if (!flags)
4083 return 0;
4084 if (flags & LSM_PRLIMIT_WRITE)
4085 av |= PROCESS__SETRLIMIT;
4086 if (flags & LSM_PRLIMIT_READ)
4087 av |= PROCESS__GETRLIMIT;
4088 return avc_has_perm(&selinux_state,
4089 cred_sid(cred), cred_sid(tcred),
4090 SECCLASS_PROCESS, av, NULL);
4091}
4092
4093static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4094 struct rlimit *new_rlim)
4095{
4096 struct rlimit *old_rlim = p->signal->rlim + resource;
4097
4098 /* Control the ability to change the hard limit (whether
4099 lowering or raising it), so that the hard limit can
4100 later be used as a safe reset point for the soft limit
4101 upon context transitions. See selinux_bprm_committing_creds. */
4102 if (old_rlim->rlim_max != new_rlim->rlim_max)
4103 return avc_has_perm(&selinux_state,
4104 current_sid(), task_sid(p),
4105 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4106
4107 return 0;
4108}
4109
4110static int selinux_task_setscheduler(struct task_struct *p)
4111{
4112 return avc_has_perm(&selinux_state,
4113 current_sid(), task_sid(p), SECCLASS_PROCESS,
4114 PROCESS__SETSCHED, NULL);
4115}
4116
4117static int selinux_task_getscheduler(struct task_struct *p)
4118{
4119 return avc_has_perm(&selinux_state,
4120 current_sid(), task_sid(p), SECCLASS_PROCESS,
4121 PROCESS__GETSCHED, NULL);
4122}
4123
4124static int selinux_task_movememory(struct task_struct *p)
4125{
4126 return avc_has_perm(&selinux_state,
4127 current_sid(), task_sid(p), SECCLASS_PROCESS,
4128 PROCESS__SETSCHED, NULL);
4129}
4130
4131static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4132 int sig, const struct cred *cred)
4133{
4134 u32 secid;
4135 u32 perm;
4136
4137 if (!sig)
4138 perm = PROCESS__SIGNULL; /* null signal; existence test */
4139 else
4140 perm = signal_to_av(sig);
4141 if (!cred)
4142 secid = current_sid();
4143 else
4144 secid = cred_sid(cred);
4145 return avc_has_perm(&selinux_state,
4146 secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4147}
4148
4149static void selinux_task_to_inode(struct task_struct *p,
4150 struct inode *inode)
4151{
4152 struct inode_security_struct *isec = selinux_inode(inode);
4153 u32 sid = task_sid(p);
4154
4155 spin_lock(&isec->lock);
4156 isec->sclass = inode_mode_to_security_class(inode->i_mode);
4157 isec->sid = sid;
4158 isec->initialized = LABEL_INITIALIZED;
4159 spin_unlock(&isec->lock);
4160}
4161
4162/* Returns error only if unable to parse addresses */
4163static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4164 struct common_audit_data *ad, u8 *proto)
4165{
4166 int offset, ihlen, ret = -EINVAL;
4167 struct iphdr _iph, *ih;
4168
4169 offset = skb_network_offset(skb);
4170 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4171 if (ih == NULL)
4172 goto out;
4173
4174 ihlen = ih->ihl * 4;
4175 if (ihlen < sizeof(_iph))
4176 goto out;
4177
4178 ad->u.net->v4info.saddr = ih->saddr;
4179 ad->u.net->v4info.daddr = ih->daddr;
4180 ret = 0;
4181
4182 if (proto)
4183 *proto = ih->protocol;
4184
4185 switch (ih->protocol) {
4186 case IPPROTO_TCP: {
4187 struct tcphdr _tcph, *th;
4188
4189 if (ntohs(ih->frag_off) & IP_OFFSET)
4190 break;
4191
4192 offset += ihlen;
4193 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4194 if (th == NULL)
4195 break;
4196
4197 ad->u.net->sport = th->source;
4198 ad->u.net->dport = th->dest;
4199 break;
4200 }
4201
4202 case IPPROTO_UDP: {
4203 struct udphdr _udph, *uh;
4204
4205 if (ntohs(ih->frag_off) & IP_OFFSET)
4206 break;
4207
4208 offset += ihlen;
4209 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4210 if (uh == NULL)
4211 break;
4212
4213 ad->u.net->sport = uh->source;
4214 ad->u.net->dport = uh->dest;
4215 break;
4216 }
4217
4218 case IPPROTO_DCCP: {
4219 struct dccp_hdr _dccph, *dh;
4220
4221 if (ntohs(ih->frag_off) & IP_OFFSET)
4222 break;
4223
4224 offset += ihlen;
4225 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4226 if (dh == NULL)
4227 break;
4228
4229 ad->u.net->sport = dh->dccph_sport;
4230 ad->u.net->dport = dh->dccph_dport;
4231 break;
4232 }
4233
4234#if IS_ENABLED(CONFIG_IP_SCTP)
4235 case IPPROTO_SCTP: {
4236 struct sctphdr _sctph, *sh;
4237
4238 if (ntohs(ih->frag_off) & IP_OFFSET)
4239 break;
4240
4241 offset += ihlen;
4242 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4243 if (sh == NULL)
4244 break;
4245
4246 ad->u.net->sport = sh->source;
4247 ad->u.net->dport = sh->dest;
4248 break;
4249 }
4250#endif
4251 default:
4252 break;
4253 }
4254out:
4255 return ret;
4256}
4257
4258#if IS_ENABLED(CONFIG_IPV6)
4259
4260/* Returns error only if unable to parse addresses */
4261static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4262 struct common_audit_data *ad, u8 *proto)
4263{
4264 u8 nexthdr;
4265 int ret = -EINVAL, offset;
4266 struct ipv6hdr _ipv6h, *ip6;
4267 __be16 frag_off;
4268
4269 offset = skb_network_offset(skb);
4270 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4271 if (ip6 == NULL)
4272 goto out;
4273
4274 ad->u.net->v6info.saddr = ip6->saddr;
4275 ad->u.net->v6info.daddr = ip6->daddr;
4276 ret = 0;
4277
4278 nexthdr = ip6->nexthdr;
4279 offset += sizeof(_ipv6h);
4280 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4281 if (offset < 0)
4282 goto out;
4283
4284 if (proto)
4285 *proto = nexthdr;
4286
4287 switch (nexthdr) {
4288 case IPPROTO_TCP: {
4289 struct tcphdr _tcph, *th;
4290
4291 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4292 if (th == NULL)
4293 break;
4294
4295 ad->u.net->sport = th->source;
4296 ad->u.net->dport = th->dest;
4297 break;
4298 }
4299
4300 case IPPROTO_UDP: {
4301 struct udphdr _udph, *uh;
4302
4303 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4304 if (uh == NULL)
4305 break;
4306
4307 ad->u.net->sport = uh->source;
4308 ad->u.net->dport = uh->dest;
4309 break;
4310 }
4311
4312 case IPPROTO_DCCP: {
4313 struct dccp_hdr _dccph, *dh;
4314
4315 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4316 if (dh == NULL)
4317 break;
4318
4319 ad->u.net->sport = dh->dccph_sport;
4320 ad->u.net->dport = dh->dccph_dport;
4321 break;
4322 }
4323
4324#if IS_ENABLED(CONFIG_IP_SCTP)
4325 case IPPROTO_SCTP: {
4326 struct sctphdr _sctph, *sh;
4327
4328 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4329 if (sh == NULL)
4330 break;
4331
4332 ad->u.net->sport = sh->source;
4333 ad->u.net->dport = sh->dest;
4334 break;
4335 }
4336#endif
4337 /* includes fragments */
4338 default:
4339 break;
4340 }
4341out:
4342 return ret;
4343}
4344
4345#endif /* IPV6 */
4346
4347static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4348 char **_addrp, int src, u8 *proto)
4349{
4350 char *addrp;
4351 int ret;
4352
4353 switch (ad->u.net->family) {
4354 case PF_INET:
4355 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4356 if (ret)
4357 goto parse_error;
4358 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4359 &ad->u.net->v4info.daddr);
4360 goto okay;
4361
4362#if IS_ENABLED(CONFIG_IPV6)
4363 case PF_INET6:
4364 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4365 if (ret)
4366 goto parse_error;
4367 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4368 &ad->u.net->v6info.daddr);
4369 goto okay;
4370#endif /* IPV6 */
4371 default:
4372 addrp = NULL;
4373 goto okay;
4374 }
4375
4376parse_error:
4377 pr_warn(
4378 "SELinux: failure in selinux_parse_skb(),"
4379 " unable to parse packet\n");
4380 return ret;
4381
4382okay:
4383 if (_addrp)
4384 *_addrp = addrp;
4385 return 0;
4386}
4387
4388/**
4389 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4390 * @skb: the packet
4391 * @family: protocol family
4392 * @sid: the packet's peer label SID
4393 *
4394 * Description:
4395 * Check the various different forms of network peer labeling and determine
4396 * the peer label/SID for the packet; most of the magic actually occurs in
4397 * the security server function security_net_peersid_cmp(). The function
4398 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4399 * or -EACCES if @sid is invalid due to inconsistencies with the different
4400 * peer labels.
4401 *
4402 */
4403static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4404{
4405 int err;
4406 u32 xfrm_sid;
4407 u32 nlbl_sid;
4408 u32 nlbl_type;
4409
4410 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4411 if (unlikely(err))
4412 return -EACCES;
4413 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4414 if (unlikely(err))
4415 return -EACCES;
4416
4417 err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4418 nlbl_type, xfrm_sid, sid);
4419 if (unlikely(err)) {
4420 pr_warn(
4421 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4422 " unable to determine packet's peer label\n");
4423 return -EACCES;
4424 }
4425
4426 return 0;
4427}
4428
4429/**
4430 * selinux_conn_sid - Determine the child socket label for a connection
4431 * @sk_sid: the parent socket's SID
4432 * @skb_sid: the packet's SID
4433 * @conn_sid: the resulting connection SID
4434 *
4435 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4436 * combined with the MLS information from @skb_sid in order to create
4437 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
4438 * of @sk_sid. Returns zero on success, negative values on failure.
4439 *
4440 */
4441static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4442{
4443 int err = 0;
4444
4445 if (skb_sid != SECSID_NULL)
4446 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4447 conn_sid);
4448 else
4449 *conn_sid = sk_sid;
4450
4451 return err;
4452}
4453
4454/* socket security operations */
4455
4456static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4457 u16 secclass, u32 *socksid)
4458{
4459 if (tsec->sockcreate_sid > SECSID_NULL) {
4460 *socksid = tsec->sockcreate_sid;
4461 return 0;
4462 }
4463
4464 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4465 secclass, NULL, socksid);
4466}
4467
4468static int sock_has_perm(struct sock *sk, u32 perms)
4469{
4470 struct sk_security_struct *sksec = sk->sk_security;
4471 struct common_audit_data ad;
4472 struct lsm_network_audit net = {0,};
4473
4474 if (sksec->sid == SECINITSID_KERNEL)
4475 return 0;
4476
4477 ad.type = LSM_AUDIT_DATA_NET;
4478 ad.u.net = &net;
4479 ad.u.net->sk = sk;
4480
4481 return avc_has_perm(&selinux_state,
4482 current_sid(), sksec->sid, sksec->sclass, perms,
4483 &ad);
4484}
4485
4486static int selinux_socket_create(int family, int type,
4487 int protocol, int kern)
4488{
4489 const struct task_security_struct *tsec = selinux_cred(current_cred());
4490 u32 newsid;
4491 u16 secclass;
4492 int rc;
4493
4494 if (kern)
4495 return 0;
4496
4497 secclass = socket_type_to_security_class(family, type, protocol);
4498 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4499 if (rc)
4500 return rc;
4501
4502 return avc_has_perm(&selinux_state,
4503 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4504}
4505
4506static int selinux_socket_post_create(struct socket *sock, int family,
4507 int type, int protocol, int kern)
4508{
4509 const struct task_security_struct *tsec = selinux_cred(current_cred());
4510 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4511 struct sk_security_struct *sksec;
4512 u16 sclass = socket_type_to_security_class(family, type, protocol);
4513 u32 sid = SECINITSID_KERNEL;
4514 int err = 0;
4515
4516 if (!kern) {
4517 err = socket_sockcreate_sid(tsec, sclass, &sid);
4518 if (err)
4519 return err;
4520 }
4521
4522 isec->sclass = sclass;
4523 isec->sid = sid;
4524 isec->initialized = LABEL_INITIALIZED;
4525
4526 if (sock->sk) {
4527 sksec = sock->sk->sk_security;
4528 sksec->sclass = sclass;
4529 sksec->sid = sid;
4530 /* Allows detection of the first association on this socket */
4531 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4532 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4533
4534 err = selinux_netlbl_socket_post_create(sock->sk, family);
4535 }
4536
4537 return err;
4538}
4539
4540static int selinux_socket_socketpair(struct socket *socka,
4541 struct socket *sockb)
4542{
4543 struct sk_security_struct *sksec_a = socka->sk->sk_security;
4544 struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4545
4546 sksec_a->peer_sid = sksec_b->sid;
4547 sksec_b->peer_sid = sksec_a->sid;
4548
4549 return 0;
4550}
4551
4552/* Range of port numbers used to automatically bind.
4553 Need to determine whether we should perform a name_bind
4554 permission check between the socket and the port number. */
4555
4556static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4557{
4558 struct sock *sk = sock->sk;
4559 struct sk_security_struct *sksec = sk->sk_security;
4560 u16 family;
4561 int err;
4562
4563 err = sock_has_perm(sk, SOCKET__BIND);
4564 if (err)
4565 goto out;
4566
4567 /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4568 family = sk->sk_family;
4569 if (family == PF_INET || family == PF_INET6) {
4570 char *addrp;
4571 struct common_audit_data ad;
4572 struct lsm_network_audit net = {0,};
4573 struct sockaddr_in *addr4 = NULL;
4574 struct sockaddr_in6 *addr6 = NULL;
4575 u16 family_sa;
4576 unsigned short snum;
4577 u32 sid, node_perm;
4578
4579 /*
4580 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4581 * that validates multiple binding addresses. Because of this
4582 * need to check address->sa_family as it is possible to have
4583 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4584 */
4585 if (addrlen < offsetofend(struct sockaddr, sa_family))
4586 return -EINVAL;
4587 family_sa = address->sa_family;
4588 switch (family_sa) {
4589 case AF_UNSPEC:
4590 case AF_INET:
4591 if (addrlen < sizeof(struct sockaddr_in))
4592 return -EINVAL;
4593 addr4 = (struct sockaddr_in *)address;
4594 if (family_sa == AF_UNSPEC) {
4595 /* see __inet_bind(), we only want to allow
4596 * AF_UNSPEC if the address is INADDR_ANY
4597 */
4598 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4599 goto err_af;
4600 family_sa = AF_INET;
4601 }
4602 snum = ntohs(addr4->sin_port);
4603 addrp = (char *)&addr4->sin_addr.s_addr;
4604 break;
4605 case AF_INET6:
4606 if (addrlen < SIN6_LEN_RFC2133)
4607 return -EINVAL;
4608 addr6 = (struct sockaddr_in6 *)address;
4609 snum = ntohs(addr6->sin6_port);
4610 addrp = (char *)&addr6->sin6_addr.s6_addr;
4611 break;
4612 default:
4613 goto err_af;
4614 }
4615
4616 ad.type = LSM_AUDIT_DATA_NET;
4617 ad.u.net = &net;
4618 ad.u.net->sport = htons(snum);
4619 ad.u.net->family = family_sa;
4620
4621 if (snum) {
4622 int low, high;
4623
4624 inet_get_local_port_range(sock_net(sk), &low, &high);
4625
4626 if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
4627 snum > high) {
4628 err = sel_netport_sid(sk->sk_protocol,
4629 snum, &sid);
4630 if (err)
4631 goto out;
4632 err = avc_has_perm(&selinux_state,
4633 sksec->sid, sid,
4634 sksec->sclass,
4635 SOCKET__NAME_BIND, &ad);
4636 if (err)
4637 goto out;
4638 }
4639 }
4640
4641 switch (sksec->sclass) {
4642 case SECCLASS_TCP_SOCKET:
4643 node_perm = TCP_SOCKET__NODE_BIND;
4644 break;
4645
4646 case SECCLASS_UDP_SOCKET:
4647 node_perm = UDP_SOCKET__NODE_BIND;
4648 break;
4649
4650 case SECCLASS_DCCP_SOCKET:
4651 node_perm = DCCP_SOCKET__NODE_BIND;
4652 break;
4653
4654 case SECCLASS_SCTP_SOCKET:
4655 node_perm = SCTP_SOCKET__NODE_BIND;
4656 break;
4657
4658 default:
4659 node_perm = RAWIP_SOCKET__NODE_BIND;
4660 break;
4661 }
4662
4663 err = sel_netnode_sid(addrp, family_sa, &sid);
4664 if (err)
4665 goto out;
4666
4667 if (family_sa == AF_INET)
4668 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4669 else
4670 ad.u.net->v6info.saddr = addr6->sin6_addr;
4671
4672 err = avc_has_perm(&selinux_state,
4673 sksec->sid, sid,
4674 sksec->sclass, node_perm, &ad);
4675 if (err)
4676 goto out;
4677 }
4678out:
4679 return err;
4680err_af:
4681 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4682 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4683 return -EINVAL;
4684 return -EAFNOSUPPORT;
4685}
4686
4687/* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4688 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4689 */
4690static int selinux_socket_connect_helper(struct socket *sock,
4691 struct sockaddr *address, int addrlen)
4692{
4693 struct sock *sk = sock->sk;
4694 struct sk_security_struct *sksec = sk->sk_security;
4695 int err;
4696
4697 err = sock_has_perm(sk, SOCKET__CONNECT);
4698 if (err)
4699 return err;
4700 if (addrlen < offsetofend(struct sockaddr, sa_family))
4701 return -EINVAL;
4702
4703 /* connect(AF_UNSPEC) has special handling, as it is a documented
4704 * way to disconnect the socket
4705 */
4706 if (address->sa_family == AF_UNSPEC)
4707 return 0;
4708
4709 /*
4710 * If a TCP, DCCP or SCTP socket, check name_connect permission
4711 * for the port.
4712 */
4713 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4714 sksec->sclass == SECCLASS_DCCP_SOCKET ||
4715 sksec->sclass == SECCLASS_SCTP_SOCKET) {
4716 struct common_audit_data ad;
4717 struct lsm_network_audit net = {0,};
4718 struct sockaddr_in *addr4 = NULL;
4719 struct sockaddr_in6 *addr6 = NULL;
4720 unsigned short snum;
4721 u32 sid, perm;
4722
4723 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4724 * that validates multiple connect addresses. Because of this
4725 * need to check address->sa_family as it is possible to have
4726 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4727 */
4728 switch (address->sa_family) {
4729 case AF_INET:
4730 addr4 = (struct sockaddr_in *)address;
4731 if (addrlen < sizeof(struct sockaddr_in))
4732 return -EINVAL;
4733 snum = ntohs(addr4->sin_port);
4734 break;
4735 case AF_INET6:
4736 addr6 = (struct sockaddr_in6 *)address;
4737 if (addrlen < SIN6_LEN_RFC2133)
4738 return -EINVAL;
4739 snum = ntohs(addr6->sin6_port);
4740 break;
4741 default:
4742 /* Note that SCTP services expect -EINVAL, whereas
4743 * others expect -EAFNOSUPPORT.
4744 */
4745 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4746 return -EINVAL;
4747 else
4748 return -EAFNOSUPPORT;
4749 }
4750
4751 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4752 if (err)
4753 return err;
4754
4755 switch (sksec->sclass) {
4756 case SECCLASS_TCP_SOCKET:
4757 perm = TCP_SOCKET__NAME_CONNECT;
4758 break;
4759 case SECCLASS_DCCP_SOCKET:
4760 perm = DCCP_SOCKET__NAME_CONNECT;
4761 break;
4762 case SECCLASS_SCTP_SOCKET:
4763 perm = SCTP_SOCKET__NAME_CONNECT;
4764 break;
4765 }
4766
4767 ad.type = LSM_AUDIT_DATA_NET;
4768 ad.u.net = &net;
4769 ad.u.net->dport = htons(snum);
4770 ad.u.net->family = address->sa_family;
4771 err = avc_has_perm(&selinux_state,
4772 sksec->sid, sid, sksec->sclass, perm, &ad);
4773 if (err)
4774 return err;
4775 }
4776
4777 return 0;
4778}
4779
4780/* Supports connect(2), see comments in selinux_socket_connect_helper() */
4781static int selinux_socket_connect(struct socket *sock,
4782 struct sockaddr *address, int addrlen)
4783{
4784 int err;
4785 struct sock *sk = sock->sk;
4786
4787 err = selinux_socket_connect_helper(sock, address, addrlen);
4788 if (err)
4789 return err;
4790
4791 return selinux_netlbl_socket_connect(sk, address);
4792}
4793
4794static int selinux_socket_listen(struct socket *sock, int backlog)
4795{
4796 return sock_has_perm(sock->sk, SOCKET__LISTEN);
4797}
4798
4799static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4800{
4801 int err;
4802 struct inode_security_struct *isec;
4803 struct inode_security_struct *newisec;
4804 u16 sclass;
4805 u32 sid;
4806
4807 err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4808 if (err)
4809 return err;
4810
4811 isec = inode_security_novalidate(SOCK_INODE(sock));
4812 spin_lock(&isec->lock);
4813 sclass = isec->sclass;
4814 sid = isec->sid;
4815 spin_unlock(&isec->lock);
4816
4817 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4818 newisec->sclass = sclass;
4819 newisec->sid = sid;
4820 newisec->initialized = LABEL_INITIALIZED;
4821
4822 return 0;
4823}
4824
4825static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4826 int size)
4827{
4828 return sock_has_perm(sock->sk, SOCKET__WRITE);
4829}
4830
4831static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4832 int size, int flags)
4833{
4834 return sock_has_perm(sock->sk, SOCKET__READ);
4835}
4836
4837static int selinux_socket_getsockname(struct socket *sock)
4838{
4839 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4840}
4841
4842static int selinux_socket_getpeername(struct socket *sock)
4843{
4844 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4845}
4846
4847static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4848{
4849 int err;
4850
4851 err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4852 if (err)
4853 return err;
4854
4855 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4856}
4857
4858static int selinux_socket_getsockopt(struct socket *sock, int level,
4859 int optname)
4860{
4861 return sock_has_perm(sock->sk, SOCKET__GETOPT);
4862}
4863
4864static int selinux_socket_shutdown(struct socket *sock, int how)
4865{
4866 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4867}
4868
4869static int selinux_socket_unix_stream_connect(struct sock *sock,
4870 struct sock *other,
4871 struct sock *newsk)
4872{
4873 struct sk_security_struct *sksec_sock = sock->sk_security;
4874 struct sk_security_struct *sksec_other = other->sk_security;
4875 struct sk_security_struct *sksec_new = newsk->sk_security;
4876 struct common_audit_data ad;
4877 struct lsm_network_audit net = {0,};
4878 int err;
4879
4880 ad.type = LSM_AUDIT_DATA_NET;
4881 ad.u.net = &net;
4882 ad.u.net->sk = other;
4883
4884 err = avc_has_perm(&selinux_state,
4885 sksec_sock->sid, sksec_other->sid,
4886 sksec_other->sclass,
4887 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4888 if (err)
4889 return err;
4890
4891 /* server child socket */
4892 sksec_new->peer_sid = sksec_sock->sid;
4893 err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4894 sksec_sock->sid, &sksec_new->sid);
4895 if (err)
4896 return err;
4897
4898 /* connecting socket */
4899 sksec_sock->peer_sid = sksec_new->sid;
4900
4901 return 0;
4902}
4903
4904static int selinux_socket_unix_may_send(struct socket *sock,
4905 struct socket *other)
4906{
4907 struct sk_security_struct *ssec = sock->sk->sk_security;
4908 struct sk_security_struct *osec = other->sk->sk_security;
4909 struct common_audit_data ad;
4910 struct lsm_network_audit net = {0,};
4911
4912 ad.type = LSM_AUDIT_DATA_NET;
4913 ad.u.net = &net;
4914 ad.u.net->sk = other->sk;
4915
4916 return avc_has_perm(&selinux_state,
4917 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4918 &ad);
4919}
4920
4921static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4922 char *addrp, u16 family, u32 peer_sid,
4923 struct common_audit_data *ad)
4924{
4925 int err;
4926 u32 if_sid;
4927 u32 node_sid;
4928
4929 err = sel_netif_sid(ns, ifindex, &if_sid);
4930 if (err)
4931 return err;
4932 err = avc_has_perm(&selinux_state,
4933 peer_sid, if_sid,
4934 SECCLASS_NETIF, NETIF__INGRESS, ad);
4935 if (err)
4936 return err;
4937
4938 err = sel_netnode_sid(addrp, family, &node_sid);
4939 if (err)
4940 return err;
4941 return avc_has_perm(&selinux_state,
4942 peer_sid, node_sid,
4943 SECCLASS_NODE, NODE__RECVFROM, ad);
4944}
4945
4946static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4947 u16 family)
4948{
4949 int err = 0;
4950 struct sk_security_struct *sksec = sk->sk_security;
4951 u32 sk_sid = sksec->sid;
4952 struct common_audit_data ad;
4953 struct lsm_network_audit net = {0,};
4954 char *addrp;
4955
4956 ad.type = LSM_AUDIT_DATA_NET;
4957 ad.u.net = &net;
4958 ad.u.net->netif = skb->skb_iif;
4959 ad.u.net->family = family;
4960 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4961 if (err)
4962 return err;
4963
4964 if (selinux_secmark_enabled()) {
4965 err = avc_has_perm(&selinux_state,
4966 sk_sid, skb->secmark, SECCLASS_PACKET,
4967 PACKET__RECV, &ad);
4968 if (err)
4969 return err;
4970 }
4971
4972 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4973 if (err)
4974 return err;
4975 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4976
4977 return err;
4978}
4979
4980static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4981{
4982 int err;
4983 struct sk_security_struct *sksec = sk->sk_security;
4984 u16 family = sk->sk_family;
4985 u32 sk_sid = sksec->sid;
4986 struct common_audit_data ad;
4987 struct lsm_network_audit net = {0,};
4988 char *addrp;
4989 u8 secmark_active;
4990 u8 peerlbl_active;
4991
4992 if (family != PF_INET && family != PF_INET6)
4993 return 0;
4994
4995 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4996 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4997 family = PF_INET;
4998
4999 /* If any sort of compatibility mode is enabled then handoff processing
5000 * to the selinux_sock_rcv_skb_compat() function to deal with the
5001 * special handling. We do this in an attempt to keep this function
5002 * as fast and as clean as possible. */
5003 if (!selinux_policycap_netpeer())
5004 return selinux_sock_rcv_skb_compat(sk, skb, family);
5005
5006 secmark_active = selinux_secmark_enabled();
5007 peerlbl_active = selinux_peerlbl_enabled();
5008 if (!secmark_active && !peerlbl_active)
5009 return 0;
5010
5011 ad.type = LSM_AUDIT_DATA_NET;
5012 ad.u.net = &net;
5013 ad.u.net->netif = skb->skb_iif;
5014 ad.u.net->family = family;
5015 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5016 if (err)
5017 return err;
5018
5019 if (peerlbl_active) {
5020 u32 peer_sid;
5021
5022 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5023 if (err)
5024 return err;
5025 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5026 addrp, family, peer_sid, &ad);
5027 if (err) {
5028 selinux_netlbl_err(skb, family, err, 0);
5029 return err;
5030 }
5031 err = avc_has_perm(&selinux_state,
5032 sk_sid, peer_sid, SECCLASS_PEER,
5033 PEER__RECV, &ad);
5034 if (err) {
5035 selinux_netlbl_err(skb, family, err, 0);
5036 return err;
5037 }
5038 }
5039
5040 if (secmark_active) {
5041 err = avc_has_perm(&selinux_state,
5042 sk_sid, skb->secmark, SECCLASS_PACKET,
5043 PACKET__RECV, &ad);
5044 if (err)
5045 return err;
5046 }
5047
5048 return err;
5049}
5050
5051static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5052 int __user *optlen, unsigned len)
5053{
5054 int err = 0;
5055 char *scontext;
5056 u32 scontext_len;
5057 struct sk_security_struct *sksec = sock->sk->sk_security;
5058 u32 peer_sid = SECSID_NULL;
5059
5060 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5061 sksec->sclass == SECCLASS_TCP_SOCKET ||
5062 sksec->sclass == SECCLASS_SCTP_SOCKET)
5063 peer_sid = sksec->peer_sid;
5064 if (peer_sid == SECSID_NULL)
5065 return -ENOPROTOOPT;
5066
5067 err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5068 &scontext_len);
5069 if (err)
5070 return err;
5071
5072 if (scontext_len > len) {
5073 err = -ERANGE;
5074 goto out_len;
5075 }
5076
5077 if (copy_to_user(optval, scontext, scontext_len))
5078 err = -EFAULT;
5079
5080out_len:
5081 if (put_user(scontext_len, optlen))
5082 err = -EFAULT;
5083 kfree(scontext);
5084 return err;
5085}
5086
5087static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5088{
5089 u32 peer_secid = SECSID_NULL;
5090 u16 family;
5091 struct inode_security_struct *isec;
5092
5093 if (skb && skb->protocol == htons(ETH_P_IP))
5094 family = PF_INET;
5095 else if (skb && skb->protocol == htons(ETH_P_IPV6))
5096 family = PF_INET6;
5097 else if (sock)
5098 family = sock->sk->sk_family;
5099 else
5100 goto out;
5101
5102 if (sock && family == PF_UNIX) {
5103 isec = inode_security_novalidate(SOCK_INODE(sock));
5104 peer_secid = isec->sid;
5105 } else if (skb)
5106 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5107
5108out:
5109 *secid = peer_secid;
5110 if (peer_secid == SECSID_NULL)
5111 return -EINVAL;
5112 return 0;
5113}
5114
5115static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5116{
5117 struct sk_security_struct *sksec;
5118
5119 sksec = kzalloc(sizeof(*sksec), priority);
5120 if (!sksec)
5121 return -ENOMEM;
5122
5123 sksec->peer_sid = SECINITSID_UNLABELED;
5124 sksec->sid = SECINITSID_UNLABELED;
5125 sksec->sclass = SECCLASS_SOCKET;
5126 selinux_netlbl_sk_security_reset(sksec);
5127 sk->sk_security = sksec;
5128
5129 return 0;
5130}
5131
5132static void selinux_sk_free_security(struct sock *sk)
5133{
5134 struct sk_security_struct *sksec = sk->sk_security;
5135
5136 sk->sk_security = NULL;
5137 selinux_netlbl_sk_security_free(sksec);
5138 kfree(sksec);
5139}
5140
5141static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5142{
5143 struct sk_security_struct *sksec = sk->sk_security;
5144 struct sk_security_struct *newsksec = newsk->sk_security;
5145
5146 newsksec->sid = sksec->sid;
5147 newsksec->peer_sid = sksec->peer_sid;
5148 newsksec->sclass = sksec->sclass;
5149
5150 selinux_netlbl_sk_security_reset(newsksec);
5151}
5152
5153static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5154{
5155 if (!sk)
5156 *secid = SECINITSID_ANY_SOCKET;
5157 else {
5158 struct sk_security_struct *sksec = sk->sk_security;
5159
5160 *secid = sksec->sid;
5161 }
5162}
5163
5164static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5165{
5166 struct inode_security_struct *isec =
5167 inode_security_novalidate(SOCK_INODE(parent));
5168 struct sk_security_struct *sksec = sk->sk_security;
5169
5170 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5171 sk->sk_family == PF_UNIX)
5172 isec->sid = sksec->sid;
5173 sksec->sclass = isec->sclass;
5174}
5175
5176/* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5177 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5178 * already present).
5179 */
5180static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5181 struct sk_buff *skb)
5182{
5183 struct sk_security_struct *sksec = ep->base.sk->sk_security;
5184 struct common_audit_data ad;
5185 struct lsm_network_audit net = {0,};
5186 u8 peerlbl_active;
5187 u32 peer_sid = SECINITSID_UNLABELED;
5188 u32 conn_sid;
5189 int err = 0;
5190
5191 if (!selinux_policycap_extsockclass())
5192 return 0;
5193
5194 peerlbl_active = selinux_peerlbl_enabled();
5195
5196 if (peerlbl_active) {
5197 /* This will return peer_sid = SECSID_NULL if there are
5198 * no peer labels, see security_net_peersid_resolve().
5199 */
5200 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5201 &peer_sid);
5202 if (err)
5203 return err;
5204
5205 if (peer_sid == SECSID_NULL)
5206 peer_sid = SECINITSID_UNLABELED;
5207 }
5208
5209 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5210 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5211
5212 /* Here as first association on socket. As the peer SID
5213 * was allowed by peer recv (and the netif/node checks),
5214 * then it is approved by policy and used as the primary
5215 * peer SID for getpeercon(3).
5216 */
5217 sksec->peer_sid = peer_sid;
5218 } else if (sksec->peer_sid != peer_sid) {
5219 /* Other association peer SIDs are checked to enforce
5220 * consistency among the peer SIDs.
5221 */
5222 ad.type = LSM_AUDIT_DATA_NET;
5223 ad.u.net = &net;
5224 ad.u.net->sk = ep->base.sk;
5225 err = avc_has_perm(&selinux_state,
5226 sksec->peer_sid, peer_sid, sksec->sclass,
5227 SCTP_SOCKET__ASSOCIATION, &ad);
5228 if (err)
5229 return err;
5230 }
5231
5232 /* Compute the MLS component for the connection and store
5233 * the information in ep. This will be used by SCTP TCP type
5234 * sockets and peeled off connections as they cause a new
5235 * socket to be generated. selinux_sctp_sk_clone() will then
5236 * plug this into the new socket.
5237 */
5238 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5239 if (err)
5240 return err;
5241
5242 ep->secid = conn_sid;
5243 ep->peer_secid = peer_sid;
5244
5245 /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5246 return selinux_netlbl_sctp_assoc_request(ep, skb);
5247}
5248
5249/* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5250 * based on their @optname.
5251 */
5252static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5253 struct sockaddr *address,
5254 int addrlen)
5255{
5256 int len, err = 0, walk_size = 0;
5257 void *addr_buf;
5258 struct sockaddr *addr;
5259 struct socket *sock;
5260
5261 if (!selinux_policycap_extsockclass())
5262 return 0;
5263
5264 /* Process one or more addresses that may be IPv4 or IPv6 */
5265 sock = sk->sk_socket;
5266 addr_buf = address;
5267
5268 while (walk_size < addrlen) {
5269 if (walk_size + sizeof(sa_family_t) > addrlen)
5270 return -EINVAL;
5271
5272 addr = addr_buf;
5273 switch (addr->sa_family) {
5274 case AF_UNSPEC:
5275 case AF_INET:
5276 len = sizeof(struct sockaddr_in);
5277 break;
5278 case AF_INET6:
5279 len = sizeof(struct sockaddr_in6);
5280 break;
5281 default:
5282 return -EINVAL;
5283 }
5284
5285 if (walk_size + len > addrlen)
5286 return -EINVAL;
5287
5288 err = -EINVAL;
5289 switch (optname) {
5290 /* Bind checks */
5291 case SCTP_PRIMARY_ADDR:
5292 case SCTP_SET_PEER_PRIMARY_ADDR:
5293 case SCTP_SOCKOPT_BINDX_ADD:
5294 err = selinux_socket_bind(sock, addr, len);
5295 break;
5296 /* Connect checks */
5297 case SCTP_SOCKOPT_CONNECTX:
5298 case SCTP_PARAM_SET_PRIMARY:
5299 case SCTP_PARAM_ADD_IP:
5300 case SCTP_SENDMSG_CONNECT:
5301 err = selinux_socket_connect_helper(sock, addr, len);
5302 if (err)
5303 return err;
5304
5305 /* As selinux_sctp_bind_connect() is called by the
5306 * SCTP protocol layer, the socket is already locked,
5307 * therefore selinux_netlbl_socket_connect_locked() is
5308 * is called here. The situations handled are:
5309 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5310 * whenever a new IP address is added or when a new
5311 * primary address is selected.
5312 * Note that an SCTP connect(2) call happens before
5313 * the SCTP protocol layer and is handled via
5314 * selinux_socket_connect().
5315 */
5316 err = selinux_netlbl_socket_connect_locked(sk, addr);
5317 break;
5318 }
5319
5320 if (err)
5321 return err;
5322
5323 addr_buf += len;
5324 walk_size += len;
5325 }
5326
5327 return 0;
5328}
5329
5330/* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5331static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5332 struct sock *newsk)
5333{
5334 struct sk_security_struct *sksec = sk->sk_security;
5335 struct sk_security_struct *newsksec = newsk->sk_security;
5336
5337 /* If policy does not support SECCLASS_SCTP_SOCKET then call
5338 * the non-sctp clone version.
5339 */
5340 if (!selinux_policycap_extsockclass())
5341 return selinux_sk_clone_security(sk, newsk);
5342
5343 newsksec->sid = ep->secid;
5344 newsksec->peer_sid = ep->peer_secid;
5345 newsksec->sclass = sksec->sclass;
5346 selinux_netlbl_sctp_sk_clone(sk, newsk);
5347}
5348
5349static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5350 struct request_sock *req)
5351{
5352 struct sk_security_struct *sksec = sk->sk_security;
5353 int err;
5354 u16 family = req->rsk_ops->family;
5355 u32 connsid;
5356 u32 peersid;
5357
5358 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5359 if (err)
5360 return err;
5361 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5362 if (err)
5363 return err;
5364 req->secid = connsid;
5365 req->peer_secid = peersid;
5366
5367 return selinux_netlbl_inet_conn_request(req, family);
5368}
5369
5370static void selinux_inet_csk_clone(struct sock *newsk,
5371 const struct request_sock *req)
5372{
5373 struct sk_security_struct *newsksec = newsk->sk_security;
5374
5375 newsksec->sid = req->secid;
5376 newsksec->peer_sid = req->peer_secid;
5377 /* NOTE: Ideally, we should also get the isec->sid for the
5378 new socket in sync, but we don't have the isec available yet.
5379 So we will wait until sock_graft to do it, by which
5380 time it will have been created and available. */
5381
5382 /* We don't need to take any sort of lock here as we are the only
5383 * thread with access to newsksec */
5384 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5385}
5386
5387static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5388{
5389 u16 family = sk->sk_family;
5390 struct sk_security_struct *sksec = sk->sk_security;
5391
5392 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5393 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5394 family = PF_INET;
5395
5396 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5397}
5398
5399static int selinux_secmark_relabel_packet(u32 sid)
5400{
5401 const struct task_security_struct *__tsec;
5402 u32 tsid;
5403
5404 __tsec = selinux_cred(current_cred());
5405 tsid = __tsec->sid;
5406
5407 return avc_has_perm(&selinux_state,
5408 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5409 NULL);
5410}
5411
5412static void selinux_secmark_refcount_inc(void)
5413{
5414 atomic_inc(&selinux_secmark_refcount);
5415}
5416
5417static void selinux_secmark_refcount_dec(void)
5418{
5419 atomic_dec(&selinux_secmark_refcount);
5420}
5421
5422static void selinux_req_classify_flow(const struct request_sock *req,
5423 struct flowi *fl)
5424{
5425 fl->flowi_secid = req->secid;
5426}
5427
5428static int selinux_tun_dev_alloc_security(void **security)
5429{
5430 struct tun_security_struct *tunsec;
5431
5432 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5433 if (!tunsec)
5434 return -ENOMEM;
5435 tunsec->sid = current_sid();
5436
5437 *security = tunsec;
5438 return 0;
5439}
5440
5441static void selinux_tun_dev_free_security(void *security)
5442{
5443 kfree(security);
5444}
5445
5446static int selinux_tun_dev_create(void)
5447{
5448 u32 sid = current_sid();
5449
5450 /* we aren't taking into account the "sockcreate" SID since the socket
5451 * that is being created here is not a socket in the traditional sense,
5452 * instead it is a private sock, accessible only to the kernel, and
5453 * representing a wide range of network traffic spanning multiple
5454 * connections unlike traditional sockets - check the TUN driver to
5455 * get a better understanding of why this socket is special */
5456
5457 return avc_has_perm(&selinux_state,
5458 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5459 NULL);
5460}
5461
5462static int selinux_tun_dev_attach_queue(void *security)
5463{
5464 struct tun_security_struct *tunsec = security;
5465
5466 return avc_has_perm(&selinux_state,
5467 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5468 TUN_SOCKET__ATTACH_QUEUE, NULL);
5469}
5470
5471static int selinux_tun_dev_attach(struct sock *sk, void *security)
5472{
5473 struct tun_security_struct *tunsec = security;
5474 struct sk_security_struct *sksec = sk->sk_security;
5475
5476 /* we don't currently perform any NetLabel based labeling here and it
5477 * isn't clear that we would want to do so anyway; while we could apply
5478 * labeling without the support of the TUN user the resulting labeled
5479 * traffic from the other end of the connection would almost certainly
5480 * cause confusion to the TUN user that had no idea network labeling
5481 * protocols were being used */
5482
5483 sksec->sid = tunsec->sid;
5484 sksec->sclass = SECCLASS_TUN_SOCKET;
5485
5486 return 0;
5487}
5488
5489static int selinux_tun_dev_open(void *security)
5490{
5491 struct tun_security_struct *tunsec = security;
5492 u32 sid = current_sid();
5493 int err;
5494
5495 err = avc_has_perm(&selinux_state,
5496 sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5497 TUN_SOCKET__RELABELFROM, NULL);
5498 if (err)
5499 return err;
5500 err = avc_has_perm(&selinux_state,
5501 sid, sid, SECCLASS_TUN_SOCKET,
5502 TUN_SOCKET__RELABELTO, NULL);
5503 if (err)
5504 return err;
5505 tunsec->sid = sid;
5506
5507 return 0;
5508}
5509
5510static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5511{
5512 int err = 0;
5513 u32 perm;
5514 struct nlmsghdr *nlh;
5515 struct sk_security_struct *sksec = sk->sk_security;
5516
5517 if (skb->len < NLMSG_HDRLEN) {
5518 err = -EINVAL;
5519 goto out;
5520 }
5521 nlh = nlmsg_hdr(skb);
5522
5523 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5524 if (err) {
5525 if (err == -EINVAL) {
5526 pr_warn_ratelimited("SELinux: unrecognized netlink"
5527 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5528 " pig=%d comm=%s\n",
5529 sk->sk_protocol, nlh->nlmsg_type,
5530 secclass_map[sksec->sclass - 1].name,
5531 task_pid_nr(current), current->comm);
5532 if (!enforcing_enabled(&selinux_state) ||
5533 security_get_allow_unknown(&selinux_state))
5534 err = 0;
5535 }
5536
5537 /* Ignore */
5538 if (err == -ENOENT)
5539 err = 0;
5540 goto out;
5541 }
5542
5543 err = sock_has_perm(sk, perm);
5544out:
5545 return err;
5546}
5547
5548#ifdef CONFIG_NETFILTER
5549
5550static unsigned int selinux_ip_forward(struct sk_buff *skb,
5551 const struct net_device *indev,
5552 u16 family)
5553{
5554 int err;
5555 char *addrp;
5556 u32 peer_sid;
5557 struct common_audit_data ad;
5558 struct lsm_network_audit net = {0,};
5559 u8 secmark_active;
5560 u8 netlbl_active;
5561 u8 peerlbl_active;
5562
5563 if (!selinux_policycap_netpeer())
5564 return NF_ACCEPT;
5565
5566 secmark_active = selinux_secmark_enabled();
5567 netlbl_active = netlbl_enabled();
5568 peerlbl_active = selinux_peerlbl_enabled();
5569 if (!secmark_active && !peerlbl_active)
5570 return NF_ACCEPT;
5571
5572 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5573 return NF_DROP;
5574
5575 ad.type = LSM_AUDIT_DATA_NET;
5576 ad.u.net = &net;
5577 ad.u.net->netif = indev->ifindex;
5578 ad.u.net->family = family;
5579 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5580 return NF_DROP;
5581
5582 if (peerlbl_active) {
5583 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5584 addrp, family, peer_sid, &ad);
5585 if (err) {
5586 selinux_netlbl_err(skb, family, err, 1);
5587 return NF_DROP;
5588 }
5589 }
5590
5591 if (secmark_active)
5592 if (avc_has_perm(&selinux_state,
5593 peer_sid, skb->secmark,
5594 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5595 return NF_DROP;
5596
5597 if (netlbl_active)
5598 /* we do this in the FORWARD path and not the POST_ROUTING
5599 * path because we want to make sure we apply the necessary
5600 * labeling before IPsec is applied so we can leverage AH
5601 * protection */
5602 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5603 return NF_DROP;
5604
5605 return NF_ACCEPT;
5606}
5607
5608static unsigned int selinux_ipv4_forward(void *priv,
5609 struct sk_buff *skb,
5610 const struct nf_hook_state *state)
5611{
5612 return selinux_ip_forward(skb, state->in, PF_INET);
5613}
5614
5615#if IS_ENABLED(CONFIG_IPV6)
5616static unsigned int selinux_ipv6_forward(void *priv,
5617 struct sk_buff *skb,
5618 const struct nf_hook_state *state)
5619{
5620 return selinux_ip_forward(skb, state->in, PF_INET6);
5621}
5622#endif /* IPV6 */
5623
5624static unsigned int selinux_ip_output(struct sk_buff *skb,
5625 u16 family)
5626{
5627 struct sock *sk;
5628 u32 sid;
5629
5630 if (!netlbl_enabled())
5631 return NF_ACCEPT;
5632
5633 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5634 * because we want to make sure we apply the necessary labeling
5635 * before IPsec is applied so we can leverage AH protection */
5636 sk = skb->sk;
5637 if (sk) {
5638 struct sk_security_struct *sksec;
5639
5640 if (sk_listener(sk))
5641 /* if the socket is the listening state then this
5642 * packet is a SYN-ACK packet which means it needs to
5643 * be labeled based on the connection/request_sock and
5644 * not the parent socket. unfortunately, we can't
5645 * lookup the request_sock yet as it isn't queued on
5646 * the parent socket until after the SYN-ACK is sent.
5647 * the "solution" is to simply pass the packet as-is
5648 * as any IP option based labeling should be copied
5649 * from the initial connection request (in the IP
5650 * layer). it is far from ideal, but until we get a
5651 * security label in the packet itself this is the
5652 * best we can do. */
5653 return NF_ACCEPT;
5654
5655 /* standard practice, label using the parent socket */
5656 sksec = sk->sk_security;
5657 sid = sksec->sid;
5658 } else
5659 sid = SECINITSID_KERNEL;
5660 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5661 return NF_DROP;
5662
5663 return NF_ACCEPT;
5664}
5665
5666static unsigned int selinux_ipv4_output(void *priv,
5667 struct sk_buff *skb,
5668 const struct nf_hook_state *state)
5669{
5670 return selinux_ip_output(skb, PF_INET);
5671}
5672
5673#if IS_ENABLED(CONFIG_IPV6)
5674static unsigned int selinux_ipv6_output(void *priv,
5675 struct sk_buff *skb,
5676 const struct nf_hook_state *state)
5677{
5678 return selinux_ip_output(skb, PF_INET6);
5679}
5680#endif /* IPV6 */
5681
5682static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5683 int ifindex,
5684 u16 family)
5685{
5686 struct sock *sk = skb_to_full_sk(skb);
5687 struct sk_security_struct *sksec;
5688 struct common_audit_data ad;
5689 struct lsm_network_audit net = {0,};
5690 char *addrp;
5691 u8 proto;
5692
5693 if (sk == NULL)
5694 return NF_ACCEPT;
5695 sksec = sk->sk_security;
5696
5697 ad.type = LSM_AUDIT_DATA_NET;
5698 ad.u.net = &net;
5699 ad.u.net->netif = ifindex;
5700 ad.u.net->family = family;
5701 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5702 return NF_DROP;
5703
5704 if (selinux_secmark_enabled())
5705 if (avc_has_perm(&selinux_state,
5706 sksec->sid, skb->secmark,
5707 SECCLASS_PACKET, PACKET__SEND, &ad))
5708 return NF_DROP_ERR(-ECONNREFUSED);
5709
5710 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5711 return NF_DROP_ERR(-ECONNREFUSED);
5712
5713 return NF_ACCEPT;
5714}
5715
5716static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5717 const struct net_device *outdev,
5718 u16 family)
5719{
5720 u32 secmark_perm;
5721 u32 peer_sid;
5722 int ifindex = outdev->ifindex;
5723 struct sock *sk;
5724 struct common_audit_data ad;
5725 struct lsm_network_audit net = {0,};
5726 char *addrp;
5727 u8 secmark_active;
5728 u8 peerlbl_active;
5729
5730 /* If any sort of compatibility mode is enabled then handoff processing
5731 * to the selinux_ip_postroute_compat() function to deal with the
5732 * special handling. We do this in an attempt to keep this function
5733 * as fast and as clean as possible. */
5734 if (!selinux_policycap_netpeer())
5735 return selinux_ip_postroute_compat(skb, ifindex, family);
5736
5737 secmark_active = selinux_secmark_enabled();
5738 peerlbl_active = selinux_peerlbl_enabled();
5739 if (!secmark_active && !peerlbl_active)
5740 return NF_ACCEPT;
5741
5742 sk = skb_to_full_sk(skb);
5743
5744#ifdef CONFIG_XFRM
5745 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5746 * packet transformation so allow the packet to pass without any checks
5747 * since we'll have another chance to perform access control checks
5748 * when the packet is on it's final way out.
5749 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5750 * is NULL, in this case go ahead and apply access control.
5751 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5752 * TCP listening state we cannot wait until the XFRM processing
5753 * is done as we will miss out on the SA label if we do;
5754 * unfortunately, this means more work, but it is only once per
5755 * connection. */
5756 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5757 !(sk && sk_listener(sk)))
5758 return NF_ACCEPT;
5759#endif
5760
5761 if (sk == NULL) {
5762 /* Without an associated socket the packet is either coming
5763 * from the kernel or it is being forwarded; check the packet
5764 * to determine which and if the packet is being forwarded
5765 * query the packet directly to determine the security label. */
5766 if (skb->skb_iif) {
5767 secmark_perm = PACKET__FORWARD_OUT;
5768 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5769 return NF_DROP;
5770 } else {
5771 secmark_perm = PACKET__SEND;
5772 peer_sid = SECINITSID_KERNEL;
5773 }
5774 } else if (sk_listener(sk)) {
5775 /* Locally generated packet but the associated socket is in the
5776 * listening state which means this is a SYN-ACK packet. In
5777 * this particular case the correct security label is assigned
5778 * to the connection/request_sock but unfortunately we can't
5779 * query the request_sock as it isn't queued on the parent
5780 * socket until after the SYN-ACK packet is sent; the only
5781 * viable choice is to regenerate the label like we do in
5782 * selinux_inet_conn_request(). See also selinux_ip_output()
5783 * for similar problems. */
5784 u32 skb_sid;
5785 struct sk_security_struct *sksec;
5786
5787 sksec = sk->sk_security;
5788 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5789 return NF_DROP;
5790 /* At this point, if the returned skb peerlbl is SECSID_NULL
5791 * and the packet has been through at least one XFRM
5792 * transformation then we must be dealing with the "final"
5793 * form of labeled IPsec packet; since we've already applied
5794 * all of our access controls on this packet we can safely
5795 * pass the packet. */
5796 if (skb_sid == SECSID_NULL) {
5797 switch (family) {
5798 case PF_INET:
5799 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5800 return NF_ACCEPT;
5801 break;
5802 case PF_INET6:
5803 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5804 return NF_ACCEPT;
5805 break;
5806 default:
5807 return NF_DROP_ERR(-ECONNREFUSED);
5808 }
5809 }
5810 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5811 return NF_DROP;
5812 secmark_perm = PACKET__SEND;
5813 } else {
5814 /* Locally generated packet, fetch the security label from the
5815 * associated socket. */
5816 struct sk_security_struct *sksec = sk->sk_security;
5817 peer_sid = sksec->sid;
5818 secmark_perm = PACKET__SEND;
5819 }
5820
5821 ad.type = LSM_AUDIT_DATA_NET;
5822 ad.u.net = &net;
5823 ad.u.net->netif = ifindex;
5824 ad.u.net->family = family;
5825 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5826 return NF_DROP;
5827
5828 if (secmark_active)
5829 if (avc_has_perm(&selinux_state,
5830 peer_sid, skb->secmark,
5831 SECCLASS_PACKET, secmark_perm, &ad))
5832 return NF_DROP_ERR(-ECONNREFUSED);
5833
5834 if (peerlbl_active) {
5835 u32 if_sid;
5836 u32 node_sid;
5837
5838 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5839 return NF_DROP;
5840 if (avc_has_perm(&selinux_state,
5841 peer_sid, if_sid,
5842 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5843 return NF_DROP_ERR(-ECONNREFUSED);
5844
5845 if (sel_netnode_sid(addrp, family, &node_sid))
5846 return NF_DROP;
5847 if (avc_has_perm(&selinux_state,
5848 peer_sid, node_sid,
5849 SECCLASS_NODE, NODE__SENDTO, &ad))
5850 return NF_DROP_ERR(-ECONNREFUSED);
5851 }
5852
5853 return NF_ACCEPT;
5854}
5855
5856static unsigned int selinux_ipv4_postroute(void *priv,
5857 struct sk_buff *skb,
5858 const struct nf_hook_state *state)
5859{
5860 return selinux_ip_postroute(skb, state->out, PF_INET);
5861}
5862
5863#if IS_ENABLED(CONFIG_IPV6)
5864static unsigned int selinux_ipv6_postroute(void *priv,
5865 struct sk_buff *skb,
5866 const struct nf_hook_state *state)
5867{
5868 return selinux_ip_postroute(skb, state->out, PF_INET6);
5869}
5870#endif /* IPV6 */
5871
5872#endif /* CONFIG_NETFILTER */
5873
5874static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5875{
5876 return selinux_nlmsg_perm(sk, skb);
5877}
5878
5879static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5880{
5881 isec->sclass = sclass;
5882 isec->sid = current_sid();
5883}
5884
5885static int msg_msg_alloc_security(struct msg_msg *msg)
5886{
5887 struct msg_security_struct *msec;
5888
5889 msec = selinux_msg_msg(msg);
5890 msec->sid = SECINITSID_UNLABELED;
5891
5892 return 0;
5893}
5894
5895static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5896 u32 perms)
5897{
5898 struct ipc_security_struct *isec;
5899 struct common_audit_data ad;
5900 u32 sid = current_sid();
5901
5902 isec = selinux_ipc(ipc_perms);
5903
5904 ad.type = LSM_AUDIT_DATA_IPC;
5905 ad.u.ipc_id = ipc_perms->key;
5906
5907 return avc_has_perm(&selinux_state,
5908 sid, isec->sid, isec->sclass, perms, &ad);
5909}
5910
5911static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5912{
5913 return msg_msg_alloc_security(msg);
5914}
5915
5916/* message queue security operations */
5917static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5918{
5919 struct ipc_security_struct *isec;
5920 struct common_audit_data ad;
5921 u32 sid = current_sid();
5922 int rc;
5923
5924 isec = selinux_ipc(msq);
5925 ipc_init_security(isec, SECCLASS_MSGQ);
5926
5927 ad.type = LSM_AUDIT_DATA_IPC;
5928 ad.u.ipc_id = msq->key;
5929
5930 rc = avc_has_perm(&selinux_state,
5931 sid, isec->sid, SECCLASS_MSGQ,
5932 MSGQ__CREATE, &ad);
5933 return rc;
5934}
5935
5936static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5937{
5938 struct ipc_security_struct *isec;
5939 struct common_audit_data ad;
5940 u32 sid = current_sid();
5941
5942 isec = selinux_ipc(msq);
5943
5944 ad.type = LSM_AUDIT_DATA_IPC;
5945 ad.u.ipc_id = msq->key;
5946
5947 return avc_has_perm(&selinux_state,
5948 sid, isec->sid, SECCLASS_MSGQ,
5949 MSGQ__ASSOCIATE, &ad);
5950}
5951
5952static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
5953{
5954 int err;
5955 int perms;
5956
5957 switch (cmd) {
5958 case IPC_INFO:
5959 case MSG_INFO:
5960 /* No specific object, just general system-wide information. */
5961 return avc_has_perm(&selinux_state,
5962 current_sid(), SECINITSID_KERNEL,
5963 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
5964 case IPC_STAT:
5965 case MSG_STAT:
5966 case MSG_STAT_ANY:
5967 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5968 break;
5969 case IPC_SET:
5970 perms = MSGQ__SETATTR;
5971 break;
5972 case IPC_RMID:
5973 perms = MSGQ__DESTROY;
5974 break;
5975 default:
5976 return 0;
5977 }
5978
5979 err = ipc_has_perm(msq, perms);
5980 return err;
5981}
5982
5983static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
5984{
5985 struct ipc_security_struct *isec;
5986 struct msg_security_struct *msec;
5987 struct common_audit_data ad;
5988 u32 sid = current_sid();
5989 int rc;
5990
5991 isec = selinux_ipc(msq);
5992 msec = selinux_msg_msg(msg);
5993
5994 /*
5995 * First time through, need to assign label to the message
5996 */
5997 if (msec->sid == SECINITSID_UNLABELED) {
5998 /*
5999 * Compute new sid based on current process and
6000 * message queue this message will be stored in
6001 */
6002 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6003 SECCLASS_MSG, NULL, &msec->sid);
6004 if (rc)
6005 return rc;
6006 }
6007
6008 ad.type = LSM_AUDIT_DATA_IPC;
6009 ad.u.ipc_id = msq->key;
6010
6011 /* Can this process write to the queue? */
6012 rc = avc_has_perm(&selinux_state,
6013 sid, isec->sid, SECCLASS_MSGQ,
6014 MSGQ__WRITE, &ad);
6015 if (!rc)
6016 /* Can this process send the message */
6017 rc = avc_has_perm(&selinux_state,
6018 sid, msec->sid, SECCLASS_MSG,
6019 MSG__SEND, &ad);
6020 if (!rc)
6021 /* Can the message be put in the queue? */
6022 rc = avc_has_perm(&selinux_state,
6023 msec->sid, isec->sid, SECCLASS_MSGQ,
6024 MSGQ__ENQUEUE, &ad);
6025
6026 return rc;
6027}
6028
6029static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6030 struct task_struct *target,
6031 long type, int mode)
6032{
6033 struct ipc_security_struct *isec;
6034 struct msg_security_struct *msec;
6035 struct common_audit_data ad;
6036 u32 sid = task_sid(target);
6037 int rc;
6038
6039 isec = selinux_ipc(msq);
6040 msec = selinux_msg_msg(msg);
6041
6042 ad.type = LSM_AUDIT_DATA_IPC;
6043 ad.u.ipc_id = msq->key;
6044
6045 rc = avc_has_perm(&selinux_state,
6046 sid, isec->sid,
6047 SECCLASS_MSGQ, MSGQ__READ, &ad);
6048 if (!rc)
6049 rc = avc_has_perm(&selinux_state,
6050 sid, msec->sid,
6051 SECCLASS_MSG, MSG__RECEIVE, &ad);
6052 return rc;
6053}
6054
6055/* Shared Memory security operations */
6056static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6057{
6058 struct ipc_security_struct *isec;
6059 struct common_audit_data ad;
6060 u32 sid = current_sid();
6061 int rc;
6062
6063 isec = selinux_ipc(shp);
6064 ipc_init_security(isec, SECCLASS_SHM);
6065
6066 ad.type = LSM_AUDIT_DATA_IPC;
6067 ad.u.ipc_id = shp->key;
6068
6069 rc = avc_has_perm(&selinux_state,
6070 sid, isec->sid, SECCLASS_SHM,
6071 SHM__CREATE, &ad);
6072 return rc;
6073}
6074
6075static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6076{
6077 struct ipc_security_struct *isec;
6078 struct common_audit_data ad;
6079 u32 sid = current_sid();
6080
6081 isec = selinux_ipc(shp);
6082
6083 ad.type = LSM_AUDIT_DATA_IPC;
6084 ad.u.ipc_id = shp->key;
6085
6086 return avc_has_perm(&selinux_state,
6087 sid, isec->sid, SECCLASS_SHM,
6088 SHM__ASSOCIATE, &ad);
6089}
6090
6091/* Note, at this point, shp is locked down */
6092static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6093{
6094 int perms;
6095 int err;
6096
6097 switch (cmd) {
6098 case IPC_INFO:
6099 case SHM_INFO:
6100 /* No specific object, just general system-wide information. */
6101 return avc_has_perm(&selinux_state,
6102 current_sid(), SECINITSID_KERNEL,
6103 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6104 case IPC_STAT:
6105 case SHM_STAT:
6106 case SHM_STAT_ANY:
6107 perms = SHM__GETATTR | SHM__ASSOCIATE;
6108 break;
6109 case IPC_SET:
6110 perms = SHM__SETATTR;
6111 break;
6112 case SHM_LOCK:
6113 case SHM_UNLOCK:
6114 perms = SHM__LOCK;
6115 break;
6116 case IPC_RMID:
6117 perms = SHM__DESTROY;
6118 break;
6119 default:
6120 return 0;
6121 }
6122
6123 err = ipc_has_perm(shp, perms);
6124 return err;
6125}
6126
6127static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6128 char __user *shmaddr, int shmflg)
6129{
6130 u32 perms;
6131
6132 if (shmflg & SHM_RDONLY)
6133 perms = SHM__READ;
6134 else
6135 perms = SHM__READ | SHM__WRITE;
6136
6137 return ipc_has_perm(shp, perms);
6138}
6139
6140/* Semaphore security operations */
6141static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6142{
6143 struct ipc_security_struct *isec;
6144 struct common_audit_data ad;
6145 u32 sid = current_sid();
6146 int rc;
6147
6148 isec = selinux_ipc(sma);
6149 ipc_init_security(isec, SECCLASS_SEM);
6150
6151 ad.type = LSM_AUDIT_DATA_IPC;
6152 ad.u.ipc_id = sma->key;
6153
6154 rc = avc_has_perm(&selinux_state,
6155 sid, isec->sid, SECCLASS_SEM,
6156 SEM__CREATE, &ad);
6157 return rc;
6158}
6159
6160static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6161{
6162 struct ipc_security_struct *isec;
6163 struct common_audit_data ad;
6164 u32 sid = current_sid();
6165
6166 isec = selinux_ipc(sma);
6167
6168 ad.type = LSM_AUDIT_DATA_IPC;
6169 ad.u.ipc_id = sma->key;
6170
6171 return avc_has_perm(&selinux_state,
6172 sid, isec->sid, SECCLASS_SEM,
6173 SEM__ASSOCIATE, &ad);
6174}
6175
6176/* Note, at this point, sma is locked down */
6177static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6178{
6179 int err;
6180 u32 perms;
6181
6182 switch (cmd) {
6183 case IPC_INFO:
6184 case SEM_INFO:
6185 /* No specific object, just general system-wide information. */
6186 return avc_has_perm(&selinux_state,
6187 current_sid(), SECINITSID_KERNEL,
6188 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6189 case GETPID:
6190 case GETNCNT:
6191 case GETZCNT:
6192 perms = SEM__GETATTR;
6193 break;
6194 case GETVAL:
6195 case GETALL:
6196 perms = SEM__READ;
6197 break;
6198 case SETVAL:
6199 case SETALL:
6200 perms = SEM__WRITE;
6201 break;
6202 case IPC_RMID:
6203 perms = SEM__DESTROY;
6204 break;
6205 case IPC_SET:
6206 perms = SEM__SETATTR;
6207 break;
6208 case IPC_STAT:
6209 case SEM_STAT:
6210 case SEM_STAT_ANY:
6211 perms = SEM__GETATTR | SEM__ASSOCIATE;
6212 break;
6213 default:
6214 return 0;
6215 }
6216
6217 err = ipc_has_perm(sma, perms);
6218 return err;
6219}
6220
6221static int selinux_sem_semop(struct kern_ipc_perm *sma,
6222 struct sembuf *sops, unsigned nsops, int alter)
6223{
6224 u32 perms;
6225
6226 if (alter)
6227 perms = SEM__READ | SEM__WRITE;
6228 else
6229 perms = SEM__READ;
6230
6231 return ipc_has_perm(sma, perms);
6232}
6233
6234static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6235{
6236 u32 av = 0;
6237
6238 av = 0;
6239 if (flag & S_IRUGO)
6240 av |= IPC__UNIX_READ;
6241 if (flag & S_IWUGO)
6242 av |= IPC__UNIX_WRITE;
6243
6244 if (av == 0)
6245 return 0;
6246
6247 return ipc_has_perm(ipcp, av);
6248}
6249
6250static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6251{
6252 struct ipc_security_struct *isec = selinux_ipc(ipcp);
6253 *secid = isec->sid;
6254}
6255
6256static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6257{
6258 if (inode)
6259 inode_doinit_with_dentry(inode, dentry);
6260}
6261
6262static int selinux_getprocattr(struct task_struct *p,
6263 char *name, char **value)
6264{
6265 const struct task_security_struct *__tsec;
6266 u32 sid;
6267 int error;
6268 unsigned len;
6269
6270 rcu_read_lock();
6271 __tsec = selinux_cred(__task_cred(p));
6272
6273 if (current != p) {
6274 error = avc_has_perm(&selinux_state,
6275 current_sid(), __tsec->sid,
6276 SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6277 if (error)
6278 goto bad;
6279 }
6280
6281 if (!strcmp(name, "current"))
6282 sid = __tsec->sid;
6283 else if (!strcmp(name, "prev"))
6284 sid = __tsec->osid;
6285 else if (!strcmp(name, "exec"))
6286 sid = __tsec->exec_sid;
6287 else if (!strcmp(name, "fscreate"))
6288 sid = __tsec->create_sid;
6289 else if (!strcmp(name, "keycreate"))
6290 sid = __tsec->keycreate_sid;
6291 else if (!strcmp(name, "sockcreate"))
6292 sid = __tsec->sockcreate_sid;
6293 else {
6294 error = -EINVAL;
6295 goto bad;
6296 }
6297 rcu_read_unlock();
6298
6299 if (!sid)
6300 return 0;
6301
6302 error = security_sid_to_context(&selinux_state, sid, value, &len);
6303 if (error)
6304 return error;
6305 return len;
6306
6307bad:
6308 rcu_read_unlock();
6309 return error;
6310}
6311
6312static int selinux_setprocattr(const char *name, void *value, size_t size)
6313{
6314 struct task_security_struct *tsec;
6315 struct cred *new;
6316 u32 mysid = current_sid(), sid = 0, ptsid;
6317 int error;
6318 char *str = value;
6319
6320 /*
6321 * Basic control over ability to set these attributes at all.
6322 */
6323 if (!strcmp(name, "exec"))
6324 error = avc_has_perm(&selinux_state,
6325 mysid, mysid, SECCLASS_PROCESS,
6326 PROCESS__SETEXEC, NULL);
6327 else if (!strcmp(name, "fscreate"))
6328 error = avc_has_perm(&selinux_state,
6329 mysid, mysid, SECCLASS_PROCESS,
6330 PROCESS__SETFSCREATE, NULL);
6331 else if (!strcmp(name, "keycreate"))
6332 error = avc_has_perm(&selinux_state,
6333 mysid, mysid, SECCLASS_PROCESS,
6334 PROCESS__SETKEYCREATE, NULL);
6335 else if (!strcmp(name, "sockcreate"))
6336 error = avc_has_perm(&selinux_state,
6337 mysid, mysid, SECCLASS_PROCESS,
6338 PROCESS__SETSOCKCREATE, NULL);
6339 else if (!strcmp(name, "current"))
6340 error = avc_has_perm(&selinux_state,
6341 mysid, mysid, SECCLASS_PROCESS,
6342 PROCESS__SETCURRENT, NULL);
6343 else
6344 error = -EINVAL;
6345 if (error)
6346 return error;
6347
6348 /* Obtain a SID for the context, if one was specified. */
6349 if (size && str[0] && str[0] != '\n') {
6350 if (str[size-1] == '\n') {
6351 str[size-1] = 0;
6352 size--;
6353 }
6354 error = security_context_to_sid(&selinux_state, value, size,
6355 &sid, GFP_KERNEL);
6356 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6357 if (!has_cap_mac_admin(true)) {
6358 struct audit_buffer *ab;
6359 size_t audit_size;
6360
6361 /* We strip a nul only if it is at the end, otherwise the
6362 * context contains a nul and we should audit that */
6363 if (str[size - 1] == '\0')
6364 audit_size = size - 1;
6365 else
6366 audit_size = size;
6367 ab = audit_log_start(audit_context(),
6368 GFP_ATOMIC,
6369 AUDIT_SELINUX_ERR);
6370 audit_log_format(ab, "op=fscreate invalid_context=");
6371 audit_log_n_untrustedstring(ab, value, audit_size);
6372 audit_log_end(ab);
6373
6374 return error;
6375 }
6376 error = security_context_to_sid_force(
6377 &selinux_state,
6378 value, size, &sid);
6379 }
6380 if (error)
6381 return error;
6382 }
6383
6384 new = prepare_creds();
6385 if (!new)
6386 return -ENOMEM;
6387
6388 /* Permission checking based on the specified context is
6389 performed during the actual operation (execve,
6390 open/mkdir/...), when we know the full context of the
6391 operation. See selinux_bprm_set_creds for the execve
6392 checks and may_create for the file creation checks. The
6393 operation will then fail if the context is not permitted. */
6394 tsec = selinux_cred(new);
6395 if (!strcmp(name, "exec")) {
6396 tsec->exec_sid = sid;
6397 } else if (!strcmp(name, "fscreate")) {
6398 tsec->create_sid = sid;
6399 } else if (!strcmp(name, "keycreate")) {
6400 if (sid) {
6401 error = avc_has_perm(&selinux_state, mysid, sid,
6402 SECCLASS_KEY, KEY__CREATE, NULL);
6403 if (error)
6404 goto abort_change;
6405 }
6406 tsec->keycreate_sid = sid;
6407 } else if (!strcmp(name, "sockcreate")) {
6408 tsec->sockcreate_sid = sid;
6409 } else if (!strcmp(name, "current")) {
6410 error = -EINVAL;
6411 if (sid == 0)
6412 goto abort_change;
6413
6414 /* Only allow single threaded processes to change context */
6415 error = -EPERM;
6416 if (!current_is_single_threaded()) {
6417 error = security_bounded_transition(&selinux_state,
6418 tsec->sid, sid);
6419 if (error)
6420 goto abort_change;
6421 }
6422
6423 /* Check permissions for the transition. */
6424 error = avc_has_perm(&selinux_state,
6425 tsec->sid, sid, SECCLASS_PROCESS,
6426 PROCESS__DYNTRANSITION, NULL);
6427 if (error)
6428 goto abort_change;
6429
6430 /* Check for ptracing, and update the task SID if ok.
6431 Otherwise, leave SID unchanged and fail. */
6432 ptsid = ptrace_parent_sid();
6433 if (ptsid != 0) {
6434 error = avc_has_perm(&selinux_state,
6435 ptsid, sid, SECCLASS_PROCESS,
6436 PROCESS__PTRACE, NULL);
6437 if (error)
6438 goto abort_change;
6439 }
6440
6441 tsec->sid = sid;
6442 } else {
6443 error = -EINVAL;
6444 goto abort_change;
6445 }
6446
6447 commit_creds(new);
6448 return size;
6449
6450abort_change:
6451 abort_creds(new);
6452 return error;
6453}
6454
6455static int selinux_ismaclabel(const char *name)
6456{
6457 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6458}
6459
6460static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6461{
6462 return security_sid_to_context(&selinux_state, secid,
6463 secdata, seclen);
6464}
6465
6466static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6467{
6468 return security_context_to_sid(&selinux_state, secdata, seclen,
6469 secid, GFP_KERNEL);
6470}
6471
6472static void selinux_release_secctx(char *secdata, u32 seclen)
6473{
6474 kfree(secdata);
6475}
6476
6477static void selinux_inode_invalidate_secctx(struct inode *inode)
6478{
6479 struct inode_security_struct *isec = selinux_inode(inode);
6480
6481 spin_lock(&isec->lock);
6482 isec->initialized = LABEL_INVALID;
6483 spin_unlock(&isec->lock);
6484}
6485
6486/*
6487 * called with inode->i_mutex locked
6488 */
6489static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6490{
6491 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6492 ctx, ctxlen, 0);
6493 /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6494 return rc == -EOPNOTSUPP ? 0 : rc;
6495}
6496
6497/*
6498 * called with inode->i_mutex locked
6499 */
6500static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6501{
6502 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6503}
6504
6505static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6506{
6507 int len = 0;
6508 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6509 ctx, true);
6510 if (len < 0)
6511 return len;
6512 *ctxlen = len;
6513 return 0;
6514}
6515#ifdef CONFIG_KEYS
6516
6517static int selinux_key_alloc(struct key *k, const struct cred *cred,
6518 unsigned long flags)
6519{
6520 const struct task_security_struct *tsec;
6521 struct key_security_struct *ksec;
6522
6523 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6524 if (!ksec)
6525 return -ENOMEM;
6526
6527 tsec = selinux_cred(cred);
6528 if (tsec->keycreate_sid)
6529 ksec->sid = tsec->keycreate_sid;
6530 else
6531 ksec->sid = tsec->sid;
6532
6533 k->security = ksec;
6534 return 0;
6535}
6536
6537static void selinux_key_free(struct key *k)
6538{
6539 struct key_security_struct *ksec = k->security;
6540
6541 k->security = NULL;
6542 kfree(ksec);
6543}
6544
6545static int selinux_key_permission(key_ref_t key_ref,
6546 const struct cred *cred,
6547 unsigned perm)
6548{
6549 struct key *key;
6550 struct key_security_struct *ksec;
6551 u32 sid;
6552
6553 /* if no specific permissions are requested, we skip the
6554 permission check. No serious, additional covert channels
6555 appear to be created. */
6556 if (perm == 0)
6557 return 0;
6558
6559 sid = cred_sid(cred);
6560
6561 key = key_ref_to_ptr(key_ref);
6562 ksec = key->security;
6563
6564 return avc_has_perm(&selinux_state,
6565 sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6566}
6567
6568static int selinux_key_getsecurity(struct key *key, char **_buffer)
6569{
6570 struct key_security_struct *ksec = key->security;
6571 char *context = NULL;
6572 unsigned len;
6573 int rc;
6574
6575 rc = security_sid_to_context(&selinux_state, ksec->sid,
6576 &context, &len);
6577 if (!rc)
6578 rc = len;
6579 *_buffer = context;
6580 return rc;
6581}
6582#endif
6583
6584#ifdef CONFIG_SECURITY_INFINIBAND
6585static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6586{
6587 struct common_audit_data ad;
6588 int err;
6589 u32 sid = 0;
6590 struct ib_security_struct *sec = ib_sec;
6591 struct lsm_ibpkey_audit ibpkey;
6592
6593 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6594 if (err)
6595 return err;
6596
6597 ad.type = LSM_AUDIT_DATA_IBPKEY;
6598 ibpkey.subnet_prefix = subnet_prefix;
6599 ibpkey.pkey = pkey_val;
6600 ad.u.ibpkey = &ibpkey;
6601 return avc_has_perm(&selinux_state,
6602 sec->sid, sid,
6603 SECCLASS_INFINIBAND_PKEY,
6604 INFINIBAND_PKEY__ACCESS, &ad);
6605}
6606
6607static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6608 u8 port_num)
6609{
6610 struct common_audit_data ad;
6611 int err;
6612 u32 sid = 0;
6613 struct ib_security_struct *sec = ib_sec;
6614 struct lsm_ibendport_audit ibendport;
6615
6616 err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6617 &sid);
6618
6619 if (err)
6620 return err;
6621
6622 ad.type = LSM_AUDIT_DATA_IBENDPORT;
6623 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6624 ibendport.port = port_num;
6625 ad.u.ibendport = &ibendport;
6626 return avc_has_perm(&selinux_state,
6627 sec->sid, sid,
6628 SECCLASS_INFINIBAND_ENDPORT,
6629 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6630}
6631
6632static int selinux_ib_alloc_security(void **ib_sec)
6633{
6634 struct ib_security_struct *sec;
6635
6636 sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6637 if (!sec)
6638 return -ENOMEM;
6639 sec->sid = current_sid();
6640
6641 *ib_sec = sec;
6642 return 0;
6643}
6644
6645static void selinux_ib_free_security(void *ib_sec)
6646{
6647 kfree(ib_sec);
6648}
6649#endif
6650
6651#ifdef CONFIG_BPF_SYSCALL
6652static int selinux_bpf(int cmd, union bpf_attr *attr,
6653 unsigned int size)
6654{
6655 u32 sid = current_sid();
6656 int ret;
6657
6658 switch (cmd) {
6659 case BPF_MAP_CREATE:
6660 ret = avc_has_perm(&selinux_state,
6661 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6662 NULL);
6663 break;
6664 case BPF_PROG_LOAD:
6665 ret = avc_has_perm(&selinux_state,
6666 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6667 NULL);
6668 break;
6669 default:
6670 ret = 0;
6671 break;
6672 }
6673
6674 return ret;
6675}
6676
6677static u32 bpf_map_fmode_to_av(fmode_t fmode)
6678{
6679 u32 av = 0;
6680
6681 if (fmode & FMODE_READ)
6682 av |= BPF__MAP_READ;
6683 if (fmode & FMODE_WRITE)
6684 av |= BPF__MAP_WRITE;
6685 return av;
6686}
6687
6688/* This function will check the file pass through unix socket or binder to see
6689 * if it is a bpf related object. And apply correspinding checks on the bpf
6690 * object based on the type. The bpf maps and programs, not like other files and
6691 * socket, are using a shared anonymous inode inside the kernel as their inode.
6692 * So checking that inode cannot identify if the process have privilege to
6693 * access the bpf object and that's why we have to add this additional check in
6694 * selinux_file_receive and selinux_binder_transfer_files.
6695 */
6696static int bpf_fd_pass(struct file *file, u32 sid)
6697{
6698 struct bpf_security_struct *bpfsec;
6699 struct bpf_prog *prog;
6700 struct bpf_map *map;
6701 int ret;
6702
6703 if (file->f_op == &bpf_map_fops) {
6704 map = file->private_data;
6705 bpfsec = map->security;
6706 ret = avc_has_perm(&selinux_state,
6707 sid, bpfsec->sid, SECCLASS_BPF,
6708 bpf_map_fmode_to_av(file->f_mode), NULL);
6709 if (ret)
6710 return ret;
6711 } else if (file->f_op == &bpf_prog_fops) {
6712 prog = file->private_data;
6713 bpfsec = prog->aux->security;
6714 ret = avc_has_perm(&selinux_state,
6715 sid, bpfsec->sid, SECCLASS_BPF,
6716 BPF__PROG_RUN, NULL);
6717 if (ret)
6718 return ret;
6719 }
6720 return 0;
6721}
6722
6723static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6724{
6725 u32 sid = current_sid();
6726 struct bpf_security_struct *bpfsec;
6727
6728 bpfsec = map->security;
6729 return avc_has_perm(&selinux_state,
6730 sid, bpfsec->sid, SECCLASS_BPF,
6731 bpf_map_fmode_to_av(fmode), NULL);
6732}
6733
6734static int selinux_bpf_prog(struct bpf_prog *prog)
6735{
6736 u32 sid = current_sid();
6737 struct bpf_security_struct *bpfsec;
6738
6739 bpfsec = prog->aux->security;
6740 return avc_has_perm(&selinux_state,
6741 sid, bpfsec->sid, SECCLASS_BPF,
6742 BPF__PROG_RUN, NULL);
6743}
6744
6745static int selinux_bpf_map_alloc(struct bpf_map *map)
6746{
6747 struct bpf_security_struct *bpfsec;
6748
6749 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6750 if (!bpfsec)
6751 return -ENOMEM;
6752
6753 bpfsec->sid = current_sid();
6754 map->security = bpfsec;
6755
6756 return 0;
6757}
6758
6759static void selinux_bpf_map_free(struct bpf_map *map)
6760{
6761 struct bpf_security_struct *bpfsec = map->security;
6762
6763 map->security = NULL;
6764 kfree(bpfsec);
6765}
6766
6767static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6768{
6769 struct bpf_security_struct *bpfsec;
6770
6771 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6772 if (!bpfsec)
6773 return -ENOMEM;
6774
6775 bpfsec->sid = current_sid();
6776 aux->security = bpfsec;
6777
6778 return 0;
6779}
6780
6781static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6782{
6783 struct bpf_security_struct *bpfsec = aux->security;
6784
6785 aux->security = NULL;
6786 kfree(bpfsec);
6787}
6788#endif
6789
6790struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
6791 .lbs_cred = sizeof(struct task_security_struct),
6792 .lbs_file = sizeof(struct file_security_struct),
6793 .lbs_inode = sizeof(struct inode_security_struct),
6794 .lbs_ipc = sizeof(struct ipc_security_struct),
6795 .lbs_msg_msg = sizeof(struct msg_security_struct),
6796};
6797
6798static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6799 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6800 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6801 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6802 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6803
6804 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6805 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6806 LSM_HOOK_INIT(capget, selinux_capget),
6807 LSM_HOOK_INIT(capset, selinux_capset),
6808 LSM_HOOK_INIT(capable, selinux_capable),
6809 LSM_HOOK_INIT(quotactl, selinux_quotactl),
6810 LSM_HOOK_INIT(quota_on, selinux_quota_on),
6811 LSM_HOOK_INIT(syslog, selinux_syslog),
6812 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6813
6814 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6815
6816 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6817 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6818 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6819
6820 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
6821 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
6822
6823 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6824 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6825 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
6826 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
6827 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6828 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6829 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6830 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6831 LSM_HOOK_INIT(sb_mount, selinux_mount),
6832 LSM_HOOK_INIT(sb_umount, selinux_umount),
6833 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6834 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6835 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
6836
6837 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6838 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6839
6840 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6841 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6842 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6843 LSM_HOOK_INIT(inode_create, selinux_inode_create),
6844 LSM_HOOK_INIT(inode_link, selinux_inode_link),
6845 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6846 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6847 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6848 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6849 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6850 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6851 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6852 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6853 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6854 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6855 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6856 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6857 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6858 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6859 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6860 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6861 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6862 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6863 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6864 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6865 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6866 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6867 LSM_HOOK_INIT(path_notify, selinux_path_notify),
6868
6869 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
6870
6871 LSM_HOOK_INIT(file_permission, selinux_file_permission),
6872 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6873 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6874 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6875 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6876 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6877 LSM_HOOK_INIT(file_lock, selinux_file_lock),
6878 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6879 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6880 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6881 LSM_HOOK_INIT(file_receive, selinux_file_receive),
6882
6883 LSM_HOOK_INIT(file_open, selinux_file_open),
6884
6885 LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
6886 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6887 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6888 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
6889 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6890 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6891 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6892 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
6893 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6894 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6895 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6896 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6897 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6898 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6899 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6900 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6901 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
6902 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6903 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6904 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6905 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6906 LSM_HOOK_INIT(task_kill, selinux_task_kill),
6907 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6908
6909 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6910 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6911
6912 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6913
6914 LSM_HOOK_INIT(msg_queue_alloc_security,
6915 selinux_msg_queue_alloc_security),
6916 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6917 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6918 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6919 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6920
6921 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6922 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6923 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6924 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6925
6926 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6927 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6928 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6929 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
6930
6931 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
6932
6933 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
6934 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
6935
6936 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
6937 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
6938 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
6939 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6940 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6941 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
6942 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
6943 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
6944
6945 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
6946 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
6947
6948 LSM_HOOK_INIT(socket_create, selinux_socket_create),
6949 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
6950 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
6951 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
6952 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
6953 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
6954 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
6955 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
6956 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
6957 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
6958 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
6959 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
6960 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
6961 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
6962 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
6963 LSM_HOOK_INIT(socket_getpeersec_stream,
6964 selinux_socket_getpeersec_stream),
6965 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
6966 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
6967 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
6968 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
6969 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
6970 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
6971 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
6972 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
6973 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
6974 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
6975 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
6976 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
6977 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
6978 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
6979 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
6980 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
6981 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
6982 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
6983 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
6984 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
6985 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
6986 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6987#ifdef CONFIG_SECURITY_INFINIBAND
6988 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
6989 LSM_HOOK_INIT(ib_endport_manage_subnet,
6990 selinux_ib_endport_manage_subnet),
6991 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
6992 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
6993#endif
6994#ifdef CONFIG_SECURITY_NETWORK_XFRM
6995 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
6996 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
6997 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
6998 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
6999 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7000 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7001 selinux_xfrm_state_alloc_acquire),
7002 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7003 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7004 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7005 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7006 selinux_xfrm_state_pol_flow_match),
7007 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7008#endif
7009
7010#ifdef CONFIG_KEYS
7011 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7012 LSM_HOOK_INIT(key_free, selinux_key_free),
7013 LSM_HOOK_INIT(key_permission, selinux_key_permission),
7014 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7015#endif
7016
7017#ifdef CONFIG_AUDIT
7018 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7019 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7020 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7021 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7022#endif
7023
7024#ifdef CONFIG_BPF_SYSCALL
7025 LSM_HOOK_INIT(bpf, selinux_bpf),
7026 LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7027 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7028 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7029 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7030 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7031 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7032#endif
7033};
7034
7035static __init int selinux_init(void)
7036{
7037 pr_info("SELinux: Initializing.\n");
7038
7039 memset(&selinux_state, 0, sizeof(selinux_state));
7040 enforcing_set(&selinux_state, selinux_enforcing_boot);
7041 selinux_state.checkreqprot = selinux_checkreqprot_boot;
7042 selinux_ss_init(&selinux_state.ss);
7043 selinux_avc_init(&selinux_state.avc);
7044
7045 /* Set the security state for the initial task. */
7046 cred_init_security();
7047
7048 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7049
7050 avc_init();
7051
7052 avtab_cache_init();
7053
7054 ebitmap_cache_init();
7055
7056 hashtab_cache_init();
7057
7058 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7059
7060 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7061 panic("SELinux: Unable to register AVC netcache callback\n");
7062
7063 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7064 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7065
7066 if (selinux_enforcing_boot)
7067 pr_debug("SELinux: Starting in enforcing mode\n");
7068 else
7069 pr_debug("SELinux: Starting in permissive mode\n");
7070
7071 fs_validate_description(&selinux_fs_parameters);
7072
7073 return 0;
7074}
7075
7076static void delayed_superblock_init(struct super_block *sb, void *unused)
7077{
7078 selinux_set_mnt_opts(sb, NULL, 0, NULL);
7079}
7080
7081void selinux_complete_init(void)
7082{
7083 pr_debug("SELinux: Completing initialization.\n");
7084
7085 /* Set up any superblocks initialized prior to the policy load. */
7086 pr_debug("SELinux: Setting up existing superblocks.\n");
7087 iterate_supers(delayed_superblock_init, NULL);
7088}
7089
7090/* SELinux requires early initialization in order to label
7091 all processes and objects when they are created. */
7092DEFINE_LSM(selinux) = {
7093 .name = "selinux",
7094 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7095 .enabled = &selinux_enabled,
7096 .blobs = &selinux_blob_sizes,
7097 .init = selinux_init,
7098};
7099
7100#if defined(CONFIG_NETFILTER)
7101
7102static const struct nf_hook_ops selinux_nf_ops[] = {
7103 {
7104 .hook = selinux_ipv4_postroute,
7105 .pf = NFPROTO_IPV4,
7106 .hooknum = NF_INET_POST_ROUTING,
7107 .priority = NF_IP_PRI_SELINUX_LAST,
7108 },
7109 {
7110 .hook = selinux_ipv4_forward,
7111 .pf = NFPROTO_IPV4,
7112 .hooknum = NF_INET_FORWARD,
7113 .priority = NF_IP_PRI_SELINUX_FIRST,
7114 },
7115 {
7116 .hook = selinux_ipv4_output,
7117 .pf = NFPROTO_IPV4,
7118 .hooknum = NF_INET_LOCAL_OUT,
7119 .priority = NF_IP_PRI_SELINUX_FIRST,
7120 },
7121#if IS_ENABLED(CONFIG_IPV6)
7122 {
7123 .hook = selinux_ipv6_postroute,
7124 .pf = NFPROTO_IPV6,
7125 .hooknum = NF_INET_POST_ROUTING,
7126 .priority = NF_IP6_PRI_SELINUX_LAST,
7127 },
7128 {
7129 .hook = selinux_ipv6_forward,
7130 .pf = NFPROTO_IPV6,
7131 .hooknum = NF_INET_FORWARD,
7132 .priority = NF_IP6_PRI_SELINUX_FIRST,
7133 },
7134 {
7135 .hook = selinux_ipv6_output,
7136 .pf = NFPROTO_IPV6,
7137 .hooknum = NF_INET_LOCAL_OUT,
7138 .priority = NF_IP6_PRI_SELINUX_FIRST,
7139 },
7140#endif /* IPV6 */
7141};
7142
7143static int __net_init selinux_nf_register(struct net *net)
7144{
7145 return nf_register_net_hooks(net, selinux_nf_ops,
7146 ARRAY_SIZE(selinux_nf_ops));
7147}
7148
7149static void __net_exit selinux_nf_unregister(struct net *net)
7150{
7151 nf_unregister_net_hooks(net, selinux_nf_ops,
7152 ARRAY_SIZE(selinux_nf_ops));
7153}
7154
7155static struct pernet_operations selinux_net_ops = {
7156 .init = selinux_nf_register,
7157 .exit = selinux_nf_unregister,
7158};
7159
7160static int __init selinux_nf_ip_init(void)
7161{
7162 int err;
7163
7164 if (!selinux_enabled)
7165 return 0;
7166
7167 pr_debug("SELinux: Registering netfilter hooks\n");
7168
7169 err = register_pernet_subsys(&selinux_net_ops);
7170 if (err)
7171 panic("SELinux: register_pernet_subsys: error %d\n", err);
7172
7173 return 0;
7174}
7175__initcall(selinux_nf_ip_init);
7176
7177#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7178static void selinux_nf_ip_exit(void)
7179{
7180 pr_debug("SELinux: Unregistering netfilter hooks\n");
7181
7182 unregister_pernet_subsys(&selinux_net_ops);
7183}
7184#endif
7185
7186#else /* CONFIG_NETFILTER */
7187
7188#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7189#define selinux_nf_ip_exit()
7190#endif
7191
7192#endif /* CONFIG_NETFILTER */
7193
7194#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7195int selinux_disable(struct selinux_state *state)
7196{
7197 if (state->initialized) {
7198 /* Not permitted after initial policy load. */
7199 return -EINVAL;
7200 }
7201
7202 if (state->disabled) {
7203 /* Only do this once. */
7204 return -EINVAL;
7205 }
7206
7207 state->disabled = 1;
7208
7209 pr_info("SELinux: Disabled at runtime.\n");
7210
7211 selinux_enabled = 0;
7212
7213 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7214
7215 /* Try to destroy the avc node cache */
7216 avc_disable();
7217
7218 /* Unregister netfilter hooks. */
7219 selinux_nf_ip_exit();
7220
7221 /* Unregister selinuxfs. */
7222 exit_sel_fs();
7223
7224 return 0;
7225}
7226#endif
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 /*
286 * The check of isec->initialized below is racy but
287 * inode_doinit_with_dentry() will recheck with
288 * isec->lock held.
289 */
290 if (selinux_initialized() &&
291 data_race(isec->initialized != LABEL_INITIALIZED)) {
292 if (!may_sleep)
293 return -ECHILD;
294
295 /*
296 * Try reloading the inode security label. This will fail if
297 * @opt_dentry is NULL and no dentry for this inode can be
298 * found; in that case, continue using the old label.
299 */
300 inode_doinit_with_dentry(inode, dentry);
301 }
302 return 0;
303}
304
305static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
306{
307 return selinux_inode(inode);
308}
309
310static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
311{
312 int error;
313
314 error = __inode_security_revalidate(inode, NULL, !rcu);
315 if (error)
316 return ERR_PTR(error);
317 return selinux_inode(inode);
318}
319
320/*
321 * Get the security label of an inode.
322 */
323static struct inode_security_struct *inode_security(struct inode *inode)
324{
325 __inode_security_revalidate(inode, NULL, true);
326 return selinux_inode(inode);
327}
328
329static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
330{
331 struct inode *inode = d_backing_inode(dentry);
332
333 return selinux_inode(inode);
334}
335
336/*
337 * Get the security label of a dentry's backing inode.
338 */
339static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
340{
341 struct inode *inode = d_backing_inode(dentry);
342
343 __inode_security_revalidate(inode, dentry, true);
344 return selinux_inode(inode);
345}
346
347static void inode_free_security(struct inode *inode)
348{
349 struct inode_security_struct *isec = selinux_inode(inode);
350 struct superblock_security_struct *sbsec;
351
352 if (!isec)
353 return;
354 sbsec = selinux_superblock(inode->i_sb);
355 /*
356 * As not all inode security structures are in a list, we check for
357 * empty list outside of the lock to make sure that we won't waste
358 * time taking a lock doing nothing.
359 *
360 * The list_del_init() function can be safely called more than once.
361 * It should not be possible for this function to be called with
362 * concurrent list_add(), but for better safety against future changes
363 * in the code, we use list_empty_careful() here.
364 */
365 if (!list_empty_careful(&isec->list)) {
366 spin_lock(&sbsec->isec_lock);
367 list_del_init(&isec->list);
368 spin_unlock(&sbsec->isec_lock);
369 }
370}
371
372struct selinux_mnt_opts {
373 u32 fscontext_sid;
374 u32 context_sid;
375 u32 rootcontext_sid;
376 u32 defcontext_sid;
377};
378
379static void selinux_free_mnt_opts(void *mnt_opts)
380{
381 kfree(mnt_opts);
382}
383
384enum {
385 Opt_error = -1,
386 Opt_context = 0,
387 Opt_defcontext = 1,
388 Opt_fscontext = 2,
389 Opt_rootcontext = 3,
390 Opt_seclabel = 4,
391};
392
393#define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
394static const struct {
395 const char *name;
396 int len;
397 int opt;
398 bool has_arg;
399} tokens[] = {
400 A(context, true),
401 A(fscontext, true),
402 A(defcontext, true),
403 A(rootcontext, true),
404 A(seclabel, false),
405};
406#undef A
407
408static int match_opt_prefix(char *s, int l, char **arg)
409{
410 int i;
411
412 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
413 size_t len = tokens[i].len;
414 if (len > l || memcmp(s, tokens[i].name, len))
415 continue;
416 if (tokens[i].has_arg) {
417 if (len == l || s[len] != '=')
418 continue;
419 *arg = s + len + 1;
420 } else if (len != l)
421 continue;
422 return tokens[i].opt;
423 }
424 return Opt_error;
425}
426
427#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
428
429static int may_context_mount_sb_relabel(u32 sid,
430 struct superblock_security_struct *sbsec,
431 const struct cred *cred)
432{
433 const struct task_security_struct *tsec = selinux_cred(cred);
434 int rc;
435
436 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
437 FILESYSTEM__RELABELFROM, NULL);
438 if (rc)
439 return rc;
440
441 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
442 FILESYSTEM__RELABELTO, NULL);
443 return rc;
444}
445
446static int may_context_mount_inode_relabel(u32 sid,
447 struct superblock_security_struct *sbsec,
448 const struct cred *cred)
449{
450 const struct task_security_struct *tsec = selinux_cred(cred);
451 int rc;
452 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
453 FILESYSTEM__RELABELFROM, NULL);
454 if (rc)
455 return rc;
456
457 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
458 FILESYSTEM__ASSOCIATE, NULL);
459 return rc;
460}
461
462static int selinux_is_genfs_special_handling(struct super_block *sb)
463{
464 /* Special handling. Genfs but also in-core setxattr handler */
465 return !strcmp(sb->s_type->name, "sysfs") ||
466 !strcmp(sb->s_type->name, "pstore") ||
467 !strcmp(sb->s_type->name, "debugfs") ||
468 !strcmp(sb->s_type->name, "tracefs") ||
469 !strcmp(sb->s_type->name, "rootfs") ||
470 (selinux_policycap_cgroupseclabel() &&
471 (!strcmp(sb->s_type->name, "cgroup") ||
472 !strcmp(sb->s_type->name, "cgroup2")));
473}
474
475static int selinux_is_sblabel_mnt(struct super_block *sb)
476{
477 struct superblock_security_struct *sbsec = selinux_superblock(sb);
478
479 /*
480 * IMPORTANT: Double-check logic in this function when adding a new
481 * SECURITY_FS_USE_* definition!
482 */
483 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
484
485 switch (sbsec->behavior) {
486 case SECURITY_FS_USE_XATTR:
487 case SECURITY_FS_USE_TRANS:
488 case SECURITY_FS_USE_TASK:
489 case SECURITY_FS_USE_NATIVE:
490 return 1;
491
492 case SECURITY_FS_USE_GENFS:
493 return selinux_is_genfs_special_handling(sb);
494
495 /* Never allow relabeling on context mounts */
496 case SECURITY_FS_USE_MNTPOINT:
497 case SECURITY_FS_USE_NONE:
498 default:
499 return 0;
500 }
501}
502
503static int sb_check_xattr_support(struct super_block *sb)
504{
505 struct superblock_security_struct *sbsec = selinux_superblock(sb);
506 struct dentry *root = sb->s_root;
507 struct inode *root_inode = d_backing_inode(root);
508 u32 sid;
509 int rc;
510
511 /*
512 * Make sure that the xattr handler exists and that no
513 * error other than -ENODATA is returned by getxattr on
514 * the root directory. -ENODATA is ok, as this may be
515 * the first boot of the SELinux kernel before we have
516 * assigned xattr values to the filesystem.
517 */
518 if (!(root_inode->i_opflags & IOP_XATTR)) {
519 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
520 sb->s_id, sb->s_type->name);
521 goto fallback;
522 }
523
524 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
525 if (rc < 0 && rc != -ENODATA) {
526 if (rc == -EOPNOTSUPP) {
527 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
528 sb->s_id, sb->s_type->name);
529 goto fallback;
530 } else {
531 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
532 sb->s_id, sb->s_type->name, -rc);
533 return rc;
534 }
535 }
536 return 0;
537
538fallback:
539 /* No xattr support - try to fallback to genfs if possible. */
540 rc = security_genfs_sid(sb->s_type->name, "/",
541 SECCLASS_DIR, &sid);
542 if (rc)
543 return -EOPNOTSUPP;
544
545 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
546 sb->s_id, sb->s_type->name);
547 sbsec->behavior = SECURITY_FS_USE_GENFS;
548 sbsec->sid = sid;
549 return 0;
550}
551
552static int sb_finish_set_opts(struct super_block *sb)
553{
554 struct superblock_security_struct *sbsec = selinux_superblock(sb);
555 struct dentry *root = sb->s_root;
556 struct inode *root_inode = d_backing_inode(root);
557 int rc = 0;
558
559 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
560 rc = sb_check_xattr_support(sb);
561 if (rc)
562 return rc;
563 }
564
565 sbsec->flags |= SE_SBINITIALIZED;
566
567 /*
568 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply
569 * leave the flag untouched because sb_clone_mnt_opts might be handing
570 * us a superblock that needs the flag to be cleared.
571 */
572 if (selinux_is_sblabel_mnt(sb))
573 sbsec->flags |= SBLABEL_MNT;
574 else
575 sbsec->flags &= ~SBLABEL_MNT;
576
577 /* Initialize the root inode. */
578 rc = inode_doinit_with_dentry(root_inode, root);
579
580 /* Initialize any other inodes associated with the superblock, e.g.
581 inodes created prior to initial policy load or inodes created
582 during get_sb by a pseudo filesystem that directly
583 populates itself. */
584 spin_lock(&sbsec->isec_lock);
585 while (!list_empty(&sbsec->isec_head)) {
586 struct inode_security_struct *isec =
587 list_first_entry(&sbsec->isec_head,
588 struct inode_security_struct, list);
589 struct inode *inode = isec->inode;
590 list_del_init(&isec->list);
591 spin_unlock(&sbsec->isec_lock);
592 inode = igrab(inode);
593 if (inode) {
594 if (!IS_PRIVATE(inode))
595 inode_doinit_with_dentry(inode, NULL);
596 iput(inode);
597 }
598 spin_lock(&sbsec->isec_lock);
599 }
600 spin_unlock(&sbsec->isec_lock);
601 return rc;
602}
603
604static int bad_option(struct superblock_security_struct *sbsec, char flag,
605 u32 old_sid, u32 new_sid)
606{
607 char mnt_flags = sbsec->flags & SE_MNTMASK;
608
609 /* check if the old mount command had the same options */
610 if (sbsec->flags & SE_SBINITIALIZED)
611 if (!(sbsec->flags & flag) ||
612 (old_sid != new_sid))
613 return 1;
614
615 /* check if we were passed the same options twice,
616 * aka someone passed context=a,context=b
617 */
618 if (!(sbsec->flags & SE_SBINITIALIZED))
619 if (mnt_flags & flag)
620 return 1;
621 return 0;
622}
623
624/*
625 * Allow filesystems with binary mount data to explicitly set mount point
626 * labeling information.
627 */
628static int selinux_set_mnt_opts(struct super_block *sb,
629 void *mnt_opts,
630 unsigned long kern_flags,
631 unsigned long *set_kern_flags)
632{
633 const struct cred *cred = current_cred();
634 struct superblock_security_struct *sbsec = selinux_superblock(sb);
635 struct dentry *root = sb->s_root;
636 struct selinux_mnt_opts *opts = mnt_opts;
637 struct inode_security_struct *root_isec;
638 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
639 u32 defcontext_sid = 0;
640 int rc = 0;
641
642 /*
643 * Specifying internal flags without providing a place to
644 * place the results is not allowed
645 */
646 if (kern_flags && !set_kern_flags)
647 return -EINVAL;
648
649 mutex_lock(&sbsec->lock);
650
651 if (!selinux_initialized()) {
652 if (!opts) {
653 /* Defer initialization until selinux_complete_init,
654 after the initial policy is loaded and the security
655 server is ready to handle calls. */
656 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
657 sbsec->flags |= SE_SBNATIVE;
658 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
659 }
660 goto out;
661 }
662 rc = -EINVAL;
663 pr_warn("SELinux: Unable to set superblock options "
664 "before the security server is initialized\n");
665 goto out;
666 }
667
668 /*
669 * Binary mount data FS will come through this function twice. Once
670 * from an explicit call and once from the generic calls from the vfs.
671 * Since the generic VFS calls will not contain any security mount data
672 * we need to skip the double mount verification.
673 *
674 * This does open a hole in which we will not notice if the first
675 * mount using this sb set explicit options and a second mount using
676 * this sb does not set any security options. (The first options
677 * will be used for both mounts)
678 */
679 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
680 && !opts)
681 goto out;
682
683 root_isec = backing_inode_security_novalidate(root);
684
685 /*
686 * parse the mount options, check if they are valid sids.
687 * also check if someone is trying to mount the same sb more
688 * than once with different security options.
689 */
690 if (opts) {
691 if (opts->fscontext_sid) {
692 fscontext_sid = opts->fscontext_sid;
693 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
694 fscontext_sid))
695 goto out_double_mount;
696 sbsec->flags |= FSCONTEXT_MNT;
697 }
698 if (opts->context_sid) {
699 context_sid = opts->context_sid;
700 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
701 context_sid))
702 goto out_double_mount;
703 sbsec->flags |= CONTEXT_MNT;
704 }
705 if (opts->rootcontext_sid) {
706 rootcontext_sid = opts->rootcontext_sid;
707 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
708 rootcontext_sid))
709 goto out_double_mount;
710 sbsec->flags |= ROOTCONTEXT_MNT;
711 }
712 if (opts->defcontext_sid) {
713 defcontext_sid = opts->defcontext_sid;
714 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
715 defcontext_sid))
716 goto out_double_mount;
717 sbsec->flags |= DEFCONTEXT_MNT;
718 }
719 }
720
721 if (sbsec->flags & SE_SBINITIALIZED) {
722 /* previously mounted with options, but not on this attempt? */
723 if ((sbsec->flags & SE_MNTMASK) && !opts)
724 goto out_double_mount;
725 rc = 0;
726 goto out;
727 }
728
729 if (strcmp(sb->s_type->name, "proc") == 0)
730 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
731
732 if (!strcmp(sb->s_type->name, "debugfs") ||
733 !strcmp(sb->s_type->name, "tracefs") ||
734 !strcmp(sb->s_type->name, "binder") ||
735 !strcmp(sb->s_type->name, "bpf") ||
736 !strcmp(sb->s_type->name, "pstore") ||
737 !strcmp(sb->s_type->name, "securityfs"))
738 sbsec->flags |= SE_SBGENFS;
739
740 if (!strcmp(sb->s_type->name, "sysfs") ||
741 !strcmp(sb->s_type->name, "cgroup") ||
742 !strcmp(sb->s_type->name, "cgroup2"))
743 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
744
745 if (!sbsec->behavior) {
746 /*
747 * Determine the labeling behavior to use for this
748 * filesystem type.
749 */
750 rc = security_fs_use(sb);
751 if (rc) {
752 pr_warn("%s: security_fs_use(%s) returned %d\n",
753 __func__, sb->s_type->name, rc);
754 goto out;
755 }
756 }
757
758 /*
759 * If this is a user namespace mount and the filesystem type is not
760 * explicitly whitelisted, then no contexts are allowed on the command
761 * line and security labels must be ignored.
762 */
763 if (sb->s_user_ns != &init_user_ns &&
764 strcmp(sb->s_type->name, "tmpfs") &&
765 strcmp(sb->s_type->name, "ramfs") &&
766 strcmp(sb->s_type->name, "devpts") &&
767 strcmp(sb->s_type->name, "overlay")) {
768 if (context_sid || fscontext_sid || rootcontext_sid ||
769 defcontext_sid) {
770 rc = -EACCES;
771 goto out;
772 }
773 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
774 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
775 rc = security_transition_sid(current_sid(),
776 current_sid(),
777 SECCLASS_FILE, NULL,
778 &sbsec->mntpoint_sid);
779 if (rc)
780 goto out;
781 }
782 goto out_set_opts;
783 }
784
785 /* sets the context of the superblock for the fs being mounted. */
786 if (fscontext_sid) {
787 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
788 if (rc)
789 goto out;
790
791 sbsec->sid = fscontext_sid;
792 }
793
794 /*
795 * Switch to using mount point labeling behavior.
796 * sets the label used on all file below the mountpoint, and will set
797 * the superblock context if not already set.
798 */
799 if (sbsec->flags & SE_SBNATIVE) {
800 /*
801 * This means we are initializing a superblock that has been
802 * mounted before the SELinux was initialized and the
803 * filesystem requested native labeling. We had already
804 * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags
805 * in the original mount attempt, so now we just need to set
806 * the SECURITY_FS_USE_NATIVE behavior.
807 */
808 sbsec->behavior = SECURITY_FS_USE_NATIVE;
809 } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
810 sbsec->behavior = SECURITY_FS_USE_NATIVE;
811 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
812 }
813
814 if (context_sid) {
815 if (!fscontext_sid) {
816 rc = may_context_mount_sb_relabel(context_sid, sbsec,
817 cred);
818 if (rc)
819 goto out;
820 sbsec->sid = context_sid;
821 } else {
822 rc = may_context_mount_inode_relabel(context_sid, sbsec,
823 cred);
824 if (rc)
825 goto out;
826 }
827 if (!rootcontext_sid)
828 rootcontext_sid = context_sid;
829
830 sbsec->mntpoint_sid = context_sid;
831 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
832 }
833
834 if (rootcontext_sid) {
835 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
836 cred);
837 if (rc)
838 goto out;
839
840 root_isec->sid = rootcontext_sid;
841 root_isec->initialized = LABEL_INITIALIZED;
842 }
843
844 if (defcontext_sid) {
845 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
846 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
847 rc = -EINVAL;
848 pr_warn("SELinux: defcontext option is "
849 "invalid for this filesystem type\n");
850 goto out;
851 }
852
853 if (defcontext_sid != sbsec->def_sid) {
854 rc = may_context_mount_inode_relabel(defcontext_sid,
855 sbsec, cred);
856 if (rc)
857 goto out;
858 }
859
860 sbsec->def_sid = defcontext_sid;
861 }
862
863out_set_opts:
864 rc = sb_finish_set_opts(sb);
865out:
866 mutex_unlock(&sbsec->lock);
867 return rc;
868out_double_mount:
869 rc = -EINVAL;
870 pr_warn("SELinux: mount invalid. Same superblock, different "
871 "security settings for (dev %s, type %s)\n", sb->s_id,
872 sb->s_type->name);
873 goto out;
874}
875
876static int selinux_cmp_sb_context(const struct super_block *oldsb,
877 const struct super_block *newsb)
878{
879 struct superblock_security_struct *old = selinux_superblock(oldsb);
880 struct superblock_security_struct *new = selinux_superblock(newsb);
881 char oldflags = old->flags & SE_MNTMASK;
882 char newflags = new->flags & SE_MNTMASK;
883
884 if (oldflags != newflags)
885 goto mismatch;
886 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
887 goto mismatch;
888 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
889 goto mismatch;
890 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
891 goto mismatch;
892 if (oldflags & ROOTCONTEXT_MNT) {
893 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
894 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
895 if (oldroot->sid != newroot->sid)
896 goto mismatch;
897 }
898 return 0;
899mismatch:
900 pr_warn("SELinux: mount invalid. Same superblock, "
901 "different security settings for (dev %s, "
902 "type %s)\n", newsb->s_id, newsb->s_type->name);
903 return -EBUSY;
904}
905
906static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
907 struct super_block *newsb,
908 unsigned long kern_flags,
909 unsigned long *set_kern_flags)
910{
911 int rc = 0;
912 const struct superblock_security_struct *oldsbsec =
913 selinux_superblock(oldsb);
914 struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
915
916 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
917 int set_context = (oldsbsec->flags & CONTEXT_MNT);
918 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
919
920 /*
921 * Specifying internal flags without providing a place to
922 * place the results is not allowed.
923 */
924 if (kern_flags && !set_kern_flags)
925 return -EINVAL;
926
927 mutex_lock(&newsbsec->lock);
928
929 /*
930 * if the parent was able to be mounted it clearly had no special lsm
931 * mount options. thus we can safely deal with this superblock later
932 */
933 if (!selinux_initialized()) {
934 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
935 newsbsec->flags |= SE_SBNATIVE;
936 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
937 }
938 goto out;
939 }
940
941 /* how can we clone if the old one wasn't set up?? */
942 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
943
944 /* if fs is reusing a sb, make sure that the contexts match */
945 if (newsbsec->flags & SE_SBINITIALIZED) {
946 mutex_unlock(&newsbsec->lock);
947 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
948 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
949 return selinux_cmp_sb_context(oldsb, newsb);
950 }
951
952 newsbsec->flags = oldsbsec->flags;
953
954 newsbsec->sid = oldsbsec->sid;
955 newsbsec->def_sid = oldsbsec->def_sid;
956 newsbsec->behavior = oldsbsec->behavior;
957
958 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
959 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
960 rc = security_fs_use(newsb);
961 if (rc)
962 goto out;
963 }
964
965 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
966 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
967 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
968 }
969
970 if (set_context) {
971 u32 sid = oldsbsec->mntpoint_sid;
972
973 if (!set_fscontext)
974 newsbsec->sid = sid;
975 if (!set_rootcontext) {
976 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
977 newisec->sid = sid;
978 }
979 newsbsec->mntpoint_sid = sid;
980 }
981 if (set_rootcontext) {
982 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
983 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
984
985 newisec->sid = oldisec->sid;
986 }
987
988 sb_finish_set_opts(newsb);
989out:
990 mutex_unlock(&newsbsec->lock);
991 return rc;
992}
993
994/*
995 * NOTE: the caller is responsible for freeing the memory even if on error.
996 */
997static int selinux_add_opt(int token, const char *s, void **mnt_opts)
998{
999 struct selinux_mnt_opts *opts = *mnt_opts;
1000 u32 *dst_sid;
1001 int rc;
1002
1003 if (token == Opt_seclabel)
1004 /* eaten and completely ignored */
1005 return 0;
1006 if (!s)
1007 return -EINVAL;
1008
1009 if (!selinux_initialized()) {
1010 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
1011 return -EINVAL;
1012 }
1013
1014 if (!opts) {
1015 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1016 if (!opts)
1017 return -ENOMEM;
1018 *mnt_opts = opts;
1019 }
1020
1021 switch (token) {
1022 case Opt_context:
1023 if (opts->context_sid || opts->defcontext_sid)
1024 goto err;
1025 dst_sid = &opts->context_sid;
1026 break;
1027 case Opt_fscontext:
1028 if (opts->fscontext_sid)
1029 goto err;
1030 dst_sid = &opts->fscontext_sid;
1031 break;
1032 case Opt_rootcontext:
1033 if (opts->rootcontext_sid)
1034 goto err;
1035 dst_sid = &opts->rootcontext_sid;
1036 break;
1037 case Opt_defcontext:
1038 if (opts->context_sid || opts->defcontext_sid)
1039 goto err;
1040 dst_sid = &opts->defcontext_sid;
1041 break;
1042 default:
1043 WARN_ON(1);
1044 return -EINVAL;
1045 }
1046 rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL);
1047 if (rc)
1048 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1049 s, rc);
1050 return rc;
1051
1052err:
1053 pr_warn(SEL_MOUNT_FAIL_MSG);
1054 return -EINVAL;
1055}
1056
1057static int show_sid(struct seq_file *m, u32 sid)
1058{
1059 char *context = NULL;
1060 u32 len;
1061 int rc;
1062
1063 rc = security_sid_to_context(sid, &context, &len);
1064 if (!rc) {
1065 bool has_comma = strchr(context, ',');
1066
1067 seq_putc(m, '=');
1068 if (has_comma)
1069 seq_putc(m, '\"');
1070 seq_escape(m, context, "\"\n\\");
1071 if (has_comma)
1072 seq_putc(m, '\"');
1073 }
1074 kfree(context);
1075 return rc;
1076}
1077
1078static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1079{
1080 struct superblock_security_struct *sbsec = selinux_superblock(sb);
1081 int rc;
1082
1083 if (!(sbsec->flags & SE_SBINITIALIZED))
1084 return 0;
1085
1086 if (!selinux_initialized())
1087 return 0;
1088
1089 if (sbsec->flags & FSCONTEXT_MNT) {
1090 seq_putc(m, ',');
1091 seq_puts(m, FSCONTEXT_STR);
1092 rc = show_sid(m, sbsec->sid);
1093 if (rc)
1094 return rc;
1095 }
1096 if (sbsec->flags & CONTEXT_MNT) {
1097 seq_putc(m, ',');
1098 seq_puts(m, CONTEXT_STR);
1099 rc = show_sid(m, sbsec->mntpoint_sid);
1100 if (rc)
1101 return rc;
1102 }
1103 if (sbsec->flags & DEFCONTEXT_MNT) {
1104 seq_putc(m, ',');
1105 seq_puts(m, DEFCONTEXT_STR);
1106 rc = show_sid(m, sbsec->def_sid);
1107 if (rc)
1108 return rc;
1109 }
1110 if (sbsec->flags & ROOTCONTEXT_MNT) {
1111 struct dentry *root = sb->s_root;
1112 struct inode_security_struct *isec = backing_inode_security(root);
1113 seq_putc(m, ',');
1114 seq_puts(m, ROOTCONTEXT_STR);
1115 rc = show_sid(m, isec->sid);
1116 if (rc)
1117 return rc;
1118 }
1119 if (sbsec->flags & SBLABEL_MNT) {
1120 seq_putc(m, ',');
1121 seq_puts(m, SECLABEL_STR);
1122 }
1123 return 0;
1124}
1125
1126static inline u16 inode_mode_to_security_class(umode_t mode)
1127{
1128 switch (mode & S_IFMT) {
1129 case S_IFSOCK:
1130 return SECCLASS_SOCK_FILE;
1131 case S_IFLNK:
1132 return SECCLASS_LNK_FILE;
1133 case S_IFREG:
1134 return SECCLASS_FILE;
1135 case S_IFBLK:
1136 return SECCLASS_BLK_FILE;
1137 case S_IFDIR:
1138 return SECCLASS_DIR;
1139 case S_IFCHR:
1140 return SECCLASS_CHR_FILE;
1141 case S_IFIFO:
1142 return SECCLASS_FIFO_FILE;
1143
1144 }
1145
1146 return SECCLASS_FILE;
1147}
1148
1149static inline int default_protocol_stream(int protocol)
1150{
1151 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1152 protocol == IPPROTO_MPTCP);
1153}
1154
1155static inline int default_protocol_dgram(int protocol)
1156{
1157 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1158}
1159
1160static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1161{
1162 bool extsockclass = selinux_policycap_extsockclass();
1163
1164 switch (family) {
1165 case PF_UNIX:
1166 switch (type) {
1167 case SOCK_STREAM:
1168 case SOCK_SEQPACKET:
1169 return SECCLASS_UNIX_STREAM_SOCKET;
1170 case SOCK_DGRAM:
1171 case SOCK_RAW:
1172 return SECCLASS_UNIX_DGRAM_SOCKET;
1173 }
1174 break;
1175 case PF_INET:
1176 case PF_INET6:
1177 switch (type) {
1178 case SOCK_STREAM:
1179 case SOCK_SEQPACKET:
1180 if (default_protocol_stream(protocol))
1181 return SECCLASS_TCP_SOCKET;
1182 else if (extsockclass && protocol == IPPROTO_SCTP)
1183 return SECCLASS_SCTP_SOCKET;
1184 else
1185 return SECCLASS_RAWIP_SOCKET;
1186 case SOCK_DGRAM:
1187 if (default_protocol_dgram(protocol))
1188 return SECCLASS_UDP_SOCKET;
1189 else if (extsockclass && (protocol == IPPROTO_ICMP ||
1190 protocol == IPPROTO_ICMPV6))
1191 return SECCLASS_ICMP_SOCKET;
1192 else
1193 return SECCLASS_RAWIP_SOCKET;
1194 case SOCK_DCCP:
1195 return SECCLASS_DCCP_SOCKET;
1196 default:
1197 return SECCLASS_RAWIP_SOCKET;
1198 }
1199 break;
1200 case PF_NETLINK:
1201 switch (protocol) {
1202 case NETLINK_ROUTE:
1203 return SECCLASS_NETLINK_ROUTE_SOCKET;
1204 case NETLINK_SOCK_DIAG:
1205 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1206 case NETLINK_NFLOG:
1207 return SECCLASS_NETLINK_NFLOG_SOCKET;
1208 case NETLINK_XFRM:
1209 return SECCLASS_NETLINK_XFRM_SOCKET;
1210 case NETLINK_SELINUX:
1211 return SECCLASS_NETLINK_SELINUX_SOCKET;
1212 case NETLINK_ISCSI:
1213 return SECCLASS_NETLINK_ISCSI_SOCKET;
1214 case NETLINK_AUDIT:
1215 return SECCLASS_NETLINK_AUDIT_SOCKET;
1216 case NETLINK_FIB_LOOKUP:
1217 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1218 case NETLINK_CONNECTOR:
1219 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1220 case NETLINK_NETFILTER:
1221 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1222 case NETLINK_DNRTMSG:
1223 return SECCLASS_NETLINK_DNRT_SOCKET;
1224 case NETLINK_KOBJECT_UEVENT:
1225 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1226 case NETLINK_GENERIC:
1227 return SECCLASS_NETLINK_GENERIC_SOCKET;
1228 case NETLINK_SCSITRANSPORT:
1229 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1230 case NETLINK_RDMA:
1231 return SECCLASS_NETLINK_RDMA_SOCKET;
1232 case NETLINK_CRYPTO:
1233 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1234 default:
1235 return SECCLASS_NETLINK_SOCKET;
1236 }
1237 case PF_PACKET:
1238 return SECCLASS_PACKET_SOCKET;
1239 case PF_KEY:
1240 return SECCLASS_KEY_SOCKET;
1241 case PF_APPLETALK:
1242 return SECCLASS_APPLETALK_SOCKET;
1243 }
1244
1245 if (extsockclass) {
1246 switch (family) {
1247 case PF_AX25:
1248 return SECCLASS_AX25_SOCKET;
1249 case PF_IPX:
1250 return SECCLASS_IPX_SOCKET;
1251 case PF_NETROM:
1252 return SECCLASS_NETROM_SOCKET;
1253 case PF_ATMPVC:
1254 return SECCLASS_ATMPVC_SOCKET;
1255 case PF_X25:
1256 return SECCLASS_X25_SOCKET;
1257 case PF_ROSE:
1258 return SECCLASS_ROSE_SOCKET;
1259 case PF_DECnet:
1260 return SECCLASS_DECNET_SOCKET;
1261 case PF_ATMSVC:
1262 return SECCLASS_ATMSVC_SOCKET;
1263 case PF_RDS:
1264 return SECCLASS_RDS_SOCKET;
1265 case PF_IRDA:
1266 return SECCLASS_IRDA_SOCKET;
1267 case PF_PPPOX:
1268 return SECCLASS_PPPOX_SOCKET;
1269 case PF_LLC:
1270 return SECCLASS_LLC_SOCKET;
1271 case PF_CAN:
1272 return SECCLASS_CAN_SOCKET;
1273 case PF_TIPC:
1274 return SECCLASS_TIPC_SOCKET;
1275 case PF_BLUETOOTH:
1276 return SECCLASS_BLUETOOTH_SOCKET;
1277 case PF_IUCV:
1278 return SECCLASS_IUCV_SOCKET;
1279 case PF_RXRPC:
1280 return SECCLASS_RXRPC_SOCKET;
1281 case PF_ISDN:
1282 return SECCLASS_ISDN_SOCKET;
1283 case PF_PHONET:
1284 return SECCLASS_PHONET_SOCKET;
1285 case PF_IEEE802154:
1286 return SECCLASS_IEEE802154_SOCKET;
1287 case PF_CAIF:
1288 return SECCLASS_CAIF_SOCKET;
1289 case PF_ALG:
1290 return SECCLASS_ALG_SOCKET;
1291 case PF_NFC:
1292 return SECCLASS_NFC_SOCKET;
1293 case PF_VSOCK:
1294 return SECCLASS_VSOCK_SOCKET;
1295 case PF_KCM:
1296 return SECCLASS_KCM_SOCKET;
1297 case PF_QIPCRTR:
1298 return SECCLASS_QIPCRTR_SOCKET;
1299 case PF_SMC:
1300 return SECCLASS_SMC_SOCKET;
1301 case PF_XDP:
1302 return SECCLASS_XDP_SOCKET;
1303 case PF_MCTP:
1304 return SECCLASS_MCTP_SOCKET;
1305#if PF_MAX > 46
1306#error New address family defined, please update this function.
1307#endif
1308 }
1309 }
1310
1311 return SECCLASS_SOCKET;
1312}
1313
1314static int selinux_genfs_get_sid(struct dentry *dentry,
1315 u16 tclass,
1316 u16 flags,
1317 u32 *sid)
1318{
1319 int rc;
1320 struct super_block *sb = dentry->d_sb;
1321 char *buffer, *path;
1322
1323 buffer = (char *)__get_free_page(GFP_KERNEL);
1324 if (!buffer)
1325 return -ENOMEM;
1326
1327 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1328 if (IS_ERR(path))
1329 rc = PTR_ERR(path);
1330 else {
1331 if (flags & SE_SBPROC) {
1332 /* each process gets a /proc/PID/ entry. Strip off the
1333 * PID part to get a valid selinux labeling.
1334 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1335 while (path[1] >= '0' && path[1] <= '9') {
1336 path[1] = '/';
1337 path++;
1338 }
1339 }
1340 rc = security_genfs_sid(sb->s_type->name,
1341 path, tclass, sid);
1342 if (rc == -ENOENT) {
1343 /* No match in policy, mark as unlabeled. */
1344 *sid = SECINITSID_UNLABELED;
1345 rc = 0;
1346 }
1347 }
1348 free_page((unsigned long)buffer);
1349 return rc;
1350}
1351
1352static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1353 u32 def_sid, u32 *sid)
1354{
1355#define INITCONTEXTLEN 255
1356 char *context;
1357 unsigned int len;
1358 int rc;
1359
1360 len = INITCONTEXTLEN;
1361 context = kmalloc(len + 1, GFP_NOFS);
1362 if (!context)
1363 return -ENOMEM;
1364
1365 context[len] = '\0';
1366 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1367 if (rc == -ERANGE) {
1368 kfree(context);
1369
1370 /* Need a larger buffer. Query for the right size. */
1371 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1372 if (rc < 0)
1373 return rc;
1374
1375 len = rc;
1376 context = kmalloc(len + 1, GFP_NOFS);
1377 if (!context)
1378 return -ENOMEM;
1379
1380 context[len] = '\0';
1381 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1382 context, len);
1383 }
1384 if (rc < 0) {
1385 kfree(context);
1386 if (rc != -ENODATA) {
1387 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n",
1388 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1389 return rc;
1390 }
1391 *sid = def_sid;
1392 return 0;
1393 }
1394
1395 rc = security_context_to_sid_default(context, rc, sid,
1396 def_sid, GFP_NOFS);
1397 if (rc) {
1398 char *dev = inode->i_sb->s_id;
1399 unsigned long ino = inode->i_ino;
1400
1401 if (rc == -EINVAL) {
1402 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",
1403 ino, dev, context);
1404 } else {
1405 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1406 __func__, context, -rc, dev, ino);
1407 }
1408 }
1409 kfree(context);
1410 return 0;
1411}
1412
1413/* The inode's security attributes must be initialized before first use. */
1414static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1415{
1416 struct superblock_security_struct *sbsec = NULL;
1417 struct inode_security_struct *isec = selinux_inode(inode);
1418 u32 task_sid, sid = 0;
1419 u16 sclass;
1420 struct dentry *dentry;
1421 int rc = 0;
1422
1423 if (isec->initialized == LABEL_INITIALIZED)
1424 return 0;
1425
1426 spin_lock(&isec->lock);
1427 if (isec->initialized == LABEL_INITIALIZED)
1428 goto out_unlock;
1429
1430 if (isec->sclass == SECCLASS_FILE)
1431 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1432
1433 sbsec = selinux_superblock(inode->i_sb);
1434 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1435 /* Defer initialization until selinux_complete_init,
1436 after the initial policy is loaded and the security
1437 server is ready to handle calls. */
1438 spin_lock(&sbsec->isec_lock);
1439 if (list_empty(&isec->list))
1440 list_add(&isec->list, &sbsec->isec_head);
1441 spin_unlock(&sbsec->isec_lock);
1442 goto out_unlock;
1443 }
1444
1445 sclass = isec->sclass;
1446 task_sid = isec->task_sid;
1447 sid = isec->sid;
1448 isec->initialized = LABEL_PENDING;
1449 spin_unlock(&isec->lock);
1450
1451 switch (sbsec->behavior) {
1452 /*
1453 * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels
1454 * via xattr when called from delayed_superblock_init().
1455 */
1456 case SECURITY_FS_USE_NATIVE:
1457 case SECURITY_FS_USE_XATTR:
1458 if (!(inode->i_opflags & IOP_XATTR)) {
1459 sid = sbsec->def_sid;
1460 break;
1461 }
1462 /* Need a dentry, since the xattr API requires one.
1463 Life would be simpler if we could just pass the inode. */
1464 if (opt_dentry) {
1465 /* Called from d_instantiate or d_splice_alias. */
1466 dentry = dget(opt_dentry);
1467 } else {
1468 /*
1469 * Called from selinux_complete_init, try to find a dentry.
1470 * Some filesystems really want a connected one, so try
1471 * that first. We could split SECURITY_FS_USE_XATTR in
1472 * two, depending upon that...
1473 */
1474 dentry = d_find_alias(inode);
1475 if (!dentry)
1476 dentry = d_find_any_alias(inode);
1477 }
1478 if (!dentry) {
1479 /*
1480 * this is can be hit on boot when a file is accessed
1481 * before the policy is loaded. When we load policy we
1482 * may find inodes that have no dentry on the
1483 * sbsec->isec_head list. No reason to complain as these
1484 * will get fixed up the next time we go through
1485 * inode_doinit with a dentry, before these inodes could
1486 * be used again by userspace.
1487 */
1488 goto out_invalid;
1489 }
1490
1491 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1492 &sid);
1493 dput(dentry);
1494 if (rc)
1495 goto out;
1496 break;
1497 case SECURITY_FS_USE_TASK:
1498 sid = task_sid;
1499 break;
1500 case SECURITY_FS_USE_TRANS:
1501 /* Default to the fs SID. */
1502 sid = sbsec->sid;
1503
1504 /* Try to obtain a transition SID. */
1505 rc = security_transition_sid(task_sid, sid,
1506 sclass, NULL, &sid);
1507 if (rc)
1508 goto out;
1509 break;
1510 case SECURITY_FS_USE_MNTPOINT:
1511 sid = sbsec->mntpoint_sid;
1512 break;
1513 default:
1514 /* Default to the fs superblock SID. */
1515 sid = sbsec->sid;
1516
1517 if ((sbsec->flags & SE_SBGENFS) &&
1518 (!S_ISLNK(inode->i_mode) ||
1519 selinux_policycap_genfs_seclabel_symlinks())) {
1520 /* We must have a dentry to determine the label on
1521 * procfs inodes */
1522 if (opt_dentry) {
1523 /* Called from d_instantiate or
1524 * d_splice_alias. */
1525 dentry = dget(opt_dentry);
1526 } else {
1527 /* Called from selinux_complete_init, try to
1528 * find a dentry. Some filesystems really want
1529 * a connected one, so try that first.
1530 */
1531 dentry = d_find_alias(inode);
1532 if (!dentry)
1533 dentry = d_find_any_alias(inode);
1534 }
1535 /*
1536 * This can be hit on boot when a file is accessed
1537 * before the policy is loaded. When we load policy we
1538 * may find inodes that have no dentry on the
1539 * sbsec->isec_head list. No reason to complain as
1540 * these will get fixed up the next time we go through
1541 * inode_doinit() with a dentry, before these inodes
1542 * could be used again by userspace.
1543 */
1544 if (!dentry)
1545 goto out_invalid;
1546 rc = selinux_genfs_get_sid(dentry, sclass,
1547 sbsec->flags, &sid);
1548 if (rc) {
1549 dput(dentry);
1550 goto out;
1551 }
1552
1553 if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1554 (inode->i_opflags & IOP_XATTR)) {
1555 rc = inode_doinit_use_xattr(inode, dentry,
1556 sid, &sid);
1557 if (rc) {
1558 dput(dentry);
1559 goto out;
1560 }
1561 }
1562 dput(dentry);
1563 }
1564 break;
1565 }
1566
1567out:
1568 spin_lock(&isec->lock);
1569 if (isec->initialized == LABEL_PENDING) {
1570 if (rc) {
1571 isec->initialized = LABEL_INVALID;
1572 goto out_unlock;
1573 }
1574 isec->initialized = LABEL_INITIALIZED;
1575 isec->sid = sid;
1576 }
1577
1578out_unlock:
1579 spin_unlock(&isec->lock);
1580 return rc;
1581
1582out_invalid:
1583 spin_lock(&isec->lock);
1584 if (isec->initialized == LABEL_PENDING) {
1585 isec->initialized = LABEL_INVALID;
1586 isec->sid = sid;
1587 }
1588 spin_unlock(&isec->lock);
1589 return 0;
1590}
1591
1592/* Convert a Linux signal to an access vector. */
1593static inline u32 signal_to_av(int sig)
1594{
1595 u32 perm = 0;
1596
1597 switch (sig) {
1598 case SIGCHLD:
1599 /* Commonly granted from child to parent. */
1600 perm = PROCESS__SIGCHLD;
1601 break;
1602 case SIGKILL:
1603 /* Cannot be caught or ignored */
1604 perm = PROCESS__SIGKILL;
1605 break;
1606 case SIGSTOP:
1607 /* Cannot be caught or ignored */
1608 perm = PROCESS__SIGSTOP;
1609 break;
1610 default:
1611 /* All other signals. */
1612 perm = PROCESS__SIGNAL;
1613 break;
1614 }
1615
1616 return perm;
1617}
1618
1619#if CAP_LAST_CAP > 63
1620#error Fix SELinux to handle capabilities > 63.
1621#endif
1622
1623/* Check whether a task is allowed to use a capability. */
1624static int cred_has_capability(const struct cred *cred,
1625 int cap, unsigned int opts, bool initns)
1626{
1627 struct common_audit_data ad;
1628 struct av_decision avd;
1629 u16 sclass;
1630 u32 sid = cred_sid(cred);
1631 u32 av = CAP_TO_MASK(cap);
1632 int rc;
1633
1634 ad.type = LSM_AUDIT_DATA_CAP;
1635 ad.u.cap = cap;
1636
1637 switch (CAP_TO_INDEX(cap)) {
1638 case 0:
1639 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1640 break;
1641 case 1:
1642 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1643 break;
1644 default:
1645 pr_err("SELinux: out of range capability %d\n", cap);
1646 BUG();
1647 return -EINVAL;
1648 }
1649
1650 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1651 if (!(opts & CAP_OPT_NOAUDIT)) {
1652 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1653 if (rc2)
1654 return rc2;
1655 }
1656 return rc;
1657}
1658
1659/* Check whether a task has a particular permission to an inode.
1660 The 'adp' parameter is optional and allows other audit
1661 data to be passed (e.g. the dentry). */
1662static int inode_has_perm(const struct cred *cred,
1663 struct inode *inode,
1664 u32 perms,
1665 struct common_audit_data *adp)
1666{
1667 struct inode_security_struct *isec;
1668 u32 sid;
1669
1670 if (unlikely(IS_PRIVATE(inode)))
1671 return 0;
1672
1673 sid = cred_sid(cred);
1674 isec = selinux_inode(inode);
1675
1676 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1677}
1678
1679/* Same as inode_has_perm, but pass explicit audit data containing
1680 the dentry to help the auditing code to more easily generate the
1681 pathname if needed. */
1682static inline int dentry_has_perm(const struct cred *cred,
1683 struct dentry *dentry,
1684 u32 av)
1685{
1686 struct inode *inode = d_backing_inode(dentry);
1687 struct common_audit_data ad;
1688
1689 ad.type = LSM_AUDIT_DATA_DENTRY;
1690 ad.u.dentry = dentry;
1691 __inode_security_revalidate(inode, dentry, true);
1692 return inode_has_perm(cred, inode, av, &ad);
1693}
1694
1695/* Same as inode_has_perm, but pass explicit audit data containing
1696 the path to help the auditing code to more easily generate the
1697 pathname if needed. */
1698static inline int path_has_perm(const struct cred *cred,
1699 const struct path *path,
1700 u32 av)
1701{
1702 struct inode *inode = d_backing_inode(path->dentry);
1703 struct common_audit_data ad;
1704
1705 ad.type = LSM_AUDIT_DATA_PATH;
1706 ad.u.path = *path;
1707 __inode_security_revalidate(inode, path->dentry, true);
1708 return inode_has_perm(cred, inode, av, &ad);
1709}
1710
1711/* Same as path_has_perm, but uses the inode from the file struct. */
1712static inline int file_path_has_perm(const struct cred *cred,
1713 struct file *file,
1714 u32 av)
1715{
1716 struct common_audit_data ad;
1717
1718 ad.type = LSM_AUDIT_DATA_FILE;
1719 ad.u.file = file;
1720 return inode_has_perm(cred, file_inode(file), av, &ad);
1721}
1722
1723#ifdef CONFIG_BPF_SYSCALL
1724static int bpf_fd_pass(const struct file *file, u32 sid);
1725#endif
1726
1727/* Check whether a task can use an open file descriptor to
1728 access an inode in a given way. Check access to the
1729 descriptor itself, and then use dentry_has_perm to
1730 check a particular permission to the file.
1731 Access to the descriptor is implicitly granted if it
1732 has the same SID as the process. If av is zero, then
1733 access to the file is not checked, e.g. for cases
1734 where only the descriptor is affected like seek. */
1735static int file_has_perm(const struct cred *cred,
1736 struct file *file,
1737 u32 av)
1738{
1739 struct file_security_struct *fsec = selinux_file(file);
1740 struct inode *inode = file_inode(file);
1741 struct common_audit_data ad;
1742 u32 sid = cred_sid(cred);
1743 int rc;
1744
1745 ad.type = LSM_AUDIT_DATA_FILE;
1746 ad.u.file = file;
1747
1748 if (sid != fsec->sid) {
1749 rc = avc_has_perm(sid, fsec->sid,
1750 SECCLASS_FD,
1751 FD__USE,
1752 &ad);
1753 if (rc)
1754 goto out;
1755 }
1756
1757#ifdef CONFIG_BPF_SYSCALL
1758 rc = bpf_fd_pass(file, cred_sid(cred));
1759 if (rc)
1760 return rc;
1761#endif
1762
1763 /* av is zero if only checking access to the descriptor. */
1764 rc = 0;
1765 if (av)
1766 rc = inode_has_perm(cred, inode, av, &ad);
1767
1768out:
1769 return rc;
1770}
1771
1772/*
1773 * Determine the label for an inode that might be unioned.
1774 */
1775static int
1776selinux_determine_inode_label(const struct task_security_struct *tsec,
1777 struct inode *dir,
1778 const struct qstr *name, u16 tclass,
1779 u32 *_new_isid)
1780{
1781 const struct superblock_security_struct *sbsec =
1782 selinux_superblock(dir->i_sb);
1783
1784 if ((sbsec->flags & SE_SBINITIALIZED) &&
1785 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1786 *_new_isid = sbsec->mntpoint_sid;
1787 } else if ((sbsec->flags & SBLABEL_MNT) &&
1788 tsec->create_sid) {
1789 *_new_isid = tsec->create_sid;
1790 } else {
1791 const struct inode_security_struct *dsec = inode_security(dir);
1792 return security_transition_sid(tsec->sid,
1793 dsec->sid, tclass,
1794 name, _new_isid);
1795 }
1796
1797 return 0;
1798}
1799
1800/* Check whether a task can create a file. */
1801static int may_create(struct inode *dir,
1802 struct dentry *dentry,
1803 u16 tclass)
1804{
1805 const struct task_security_struct *tsec = selinux_cred(current_cred());
1806 struct inode_security_struct *dsec;
1807 struct superblock_security_struct *sbsec;
1808 u32 sid, newsid;
1809 struct common_audit_data ad;
1810 int rc;
1811
1812 dsec = inode_security(dir);
1813 sbsec = selinux_superblock(dir->i_sb);
1814
1815 sid = tsec->sid;
1816
1817 ad.type = LSM_AUDIT_DATA_DENTRY;
1818 ad.u.dentry = dentry;
1819
1820 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1821 DIR__ADD_NAME | DIR__SEARCH,
1822 &ad);
1823 if (rc)
1824 return rc;
1825
1826 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1827 &newsid);
1828 if (rc)
1829 return rc;
1830
1831 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1832 if (rc)
1833 return rc;
1834
1835 return avc_has_perm(newsid, sbsec->sid,
1836 SECCLASS_FILESYSTEM,
1837 FILESYSTEM__ASSOCIATE, &ad);
1838}
1839
1840#define MAY_LINK 0
1841#define MAY_UNLINK 1
1842#define MAY_RMDIR 2
1843
1844/* Check whether a task can link, unlink, or rmdir a file/directory. */
1845static int may_link(struct inode *dir,
1846 struct dentry *dentry,
1847 int kind)
1848
1849{
1850 struct inode_security_struct *dsec, *isec;
1851 struct common_audit_data ad;
1852 u32 sid = current_sid();
1853 u32 av;
1854 int rc;
1855
1856 dsec = inode_security(dir);
1857 isec = backing_inode_security(dentry);
1858
1859 ad.type = LSM_AUDIT_DATA_DENTRY;
1860 ad.u.dentry = dentry;
1861
1862 av = DIR__SEARCH;
1863 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1864 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1865 if (rc)
1866 return rc;
1867
1868 switch (kind) {
1869 case MAY_LINK:
1870 av = FILE__LINK;
1871 break;
1872 case MAY_UNLINK:
1873 av = FILE__UNLINK;
1874 break;
1875 case MAY_RMDIR:
1876 av = DIR__RMDIR;
1877 break;
1878 default:
1879 pr_warn("SELinux: %s: unrecognized kind %d\n",
1880 __func__, kind);
1881 return 0;
1882 }
1883
1884 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1885 return rc;
1886}
1887
1888static inline int may_rename(struct inode *old_dir,
1889 struct dentry *old_dentry,
1890 struct inode *new_dir,
1891 struct dentry *new_dentry)
1892{
1893 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1894 struct common_audit_data ad;
1895 u32 sid = current_sid();
1896 u32 av;
1897 int old_is_dir, new_is_dir;
1898 int rc;
1899
1900 old_dsec = inode_security(old_dir);
1901 old_isec = backing_inode_security(old_dentry);
1902 old_is_dir = d_is_dir(old_dentry);
1903 new_dsec = inode_security(new_dir);
1904
1905 ad.type = LSM_AUDIT_DATA_DENTRY;
1906
1907 ad.u.dentry = old_dentry;
1908 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1909 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1910 if (rc)
1911 return rc;
1912 rc = avc_has_perm(sid, old_isec->sid,
1913 old_isec->sclass, FILE__RENAME, &ad);
1914 if (rc)
1915 return rc;
1916 if (old_is_dir && new_dir != old_dir) {
1917 rc = avc_has_perm(sid, old_isec->sid,
1918 old_isec->sclass, DIR__REPARENT, &ad);
1919 if (rc)
1920 return rc;
1921 }
1922
1923 ad.u.dentry = new_dentry;
1924 av = DIR__ADD_NAME | DIR__SEARCH;
1925 if (d_is_positive(new_dentry))
1926 av |= DIR__REMOVE_NAME;
1927 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1928 if (rc)
1929 return rc;
1930 if (d_is_positive(new_dentry)) {
1931 new_isec = backing_inode_security(new_dentry);
1932 new_is_dir = d_is_dir(new_dentry);
1933 rc = avc_has_perm(sid, new_isec->sid,
1934 new_isec->sclass,
1935 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1936 if (rc)
1937 return rc;
1938 }
1939
1940 return 0;
1941}
1942
1943/* Check whether a task can perform a filesystem operation. */
1944static int superblock_has_perm(const struct cred *cred,
1945 const struct super_block *sb,
1946 u32 perms,
1947 struct common_audit_data *ad)
1948{
1949 struct superblock_security_struct *sbsec;
1950 u32 sid = cred_sid(cred);
1951
1952 sbsec = selinux_superblock(sb);
1953 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1954}
1955
1956/* Convert a Linux mode and permission mask to an access vector. */
1957static inline u32 file_mask_to_av(int mode, int mask)
1958{
1959 u32 av = 0;
1960
1961 if (!S_ISDIR(mode)) {
1962 if (mask & MAY_EXEC)
1963 av |= FILE__EXECUTE;
1964 if (mask & MAY_READ)
1965 av |= FILE__READ;
1966
1967 if (mask & MAY_APPEND)
1968 av |= FILE__APPEND;
1969 else if (mask & MAY_WRITE)
1970 av |= FILE__WRITE;
1971
1972 } else {
1973 if (mask & MAY_EXEC)
1974 av |= DIR__SEARCH;
1975 if (mask & MAY_WRITE)
1976 av |= DIR__WRITE;
1977 if (mask & MAY_READ)
1978 av |= DIR__READ;
1979 }
1980
1981 return av;
1982}
1983
1984/* Convert a Linux file to an access vector. */
1985static inline u32 file_to_av(const struct file *file)
1986{
1987 u32 av = 0;
1988
1989 if (file->f_mode & FMODE_READ)
1990 av |= FILE__READ;
1991 if (file->f_mode & FMODE_WRITE) {
1992 if (file->f_flags & O_APPEND)
1993 av |= FILE__APPEND;
1994 else
1995 av |= FILE__WRITE;
1996 }
1997 if (!av) {
1998 /*
1999 * Special file opened with flags 3 for ioctl-only use.
2000 */
2001 av = FILE__IOCTL;
2002 }
2003
2004 return av;
2005}
2006
2007/*
2008 * Convert a file to an access vector and include the correct
2009 * open permission.
2010 */
2011static inline u32 open_file_to_av(struct file *file)
2012{
2013 u32 av = file_to_av(file);
2014 struct inode *inode = file_inode(file);
2015
2016 if (selinux_policycap_openperm() &&
2017 inode->i_sb->s_magic != SOCKFS_MAGIC)
2018 av |= FILE__OPEN;
2019
2020 return av;
2021}
2022
2023/* Hook functions begin here. */
2024
2025static int selinux_binder_set_context_mgr(const struct cred *mgr)
2026{
2027 return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER,
2028 BINDER__SET_CONTEXT_MGR, NULL);
2029}
2030
2031static int selinux_binder_transaction(const struct cred *from,
2032 const struct cred *to)
2033{
2034 u32 mysid = current_sid();
2035 u32 fromsid = cred_sid(from);
2036 u32 tosid = cred_sid(to);
2037 int rc;
2038
2039 if (mysid != fromsid) {
2040 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2041 BINDER__IMPERSONATE, NULL);
2042 if (rc)
2043 return rc;
2044 }
2045
2046 return avc_has_perm(fromsid, tosid,
2047 SECCLASS_BINDER, BINDER__CALL, NULL);
2048}
2049
2050static int selinux_binder_transfer_binder(const struct cred *from,
2051 const struct cred *to)
2052{
2053 return avc_has_perm(cred_sid(from), cred_sid(to),
2054 SECCLASS_BINDER, BINDER__TRANSFER,
2055 NULL);
2056}
2057
2058static int selinux_binder_transfer_file(const struct cred *from,
2059 const struct cred *to,
2060 const struct file *file)
2061{
2062 u32 sid = cred_sid(to);
2063 struct file_security_struct *fsec = selinux_file(file);
2064 struct dentry *dentry = file->f_path.dentry;
2065 struct inode_security_struct *isec;
2066 struct common_audit_data ad;
2067 int rc;
2068
2069 ad.type = LSM_AUDIT_DATA_PATH;
2070 ad.u.path = file->f_path;
2071
2072 if (sid != fsec->sid) {
2073 rc = avc_has_perm(sid, fsec->sid,
2074 SECCLASS_FD,
2075 FD__USE,
2076 &ad);
2077 if (rc)
2078 return rc;
2079 }
2080
2081#ifdef CONFIG_BPF_SYSCALL
2082 rc = bpf_fd_pass(file, sid);
2083 if (rc)
2084 return rc;
2085#endif
2086
2087 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2088 return 0;
2089
2090 isec = backing_inode_security(dentry);
2091 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2092 &ad);
2093}
2094
2095static int selinux_ptrace_access_check(struct task_struct *child,
2096 unsigned int mode)
2097{
2098 u32 sid = current_sid();
2099 u32 csid = task_sid_obj(child);
2100
2101 if (mode & PTRACE_MODE_READ)
2102 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ,
2103 NULL);
2104
2105 return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE,
2106 NULL);
2107}
2108
2109static int selinux_ptrace_traceme(struct task_struct *parent)
2110{
2111 return avc_has_perm(task_sid_obj(parent), task_sid_obj(current),
2112 SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2113}
2114
2115static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective,
2116 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2117{
2118 return avc_has_perm(current_sid(), task_sid_obj(target),
2119 SECCLASS_PROCESS, PROCESS__GETCAP, NULL);
2120}
2121
2122static int selinux_capset(struct cred *new, const struct cred *old,
2123 const kernel_cap_t *effective,
2124 const kernel_cap_t *inheritable,
2125 const kernel_cap_t *permitted)
2126{
2127 return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2128 PROCESS__SETCAP, NULL);
2129}
2130
2131/*
2132 * (This comment used to live with the selinux_task_setuid hook,
2133 * which was removed).
2134 *
2135 * Since setuid only affects the current process, and since the SELinux
2136 * controls are not based on the Linux identity attributes, SELinux does not
2137 * need to control this operation. However, SELinux does control the use of
2138 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2139 */
2140
2141static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2142 int cap, unsigned int opts)
2143{
2144 return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2145}
2146
2147static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb)
2148{
2149 const struct cred *cred = current_cred();
2150 int rc = 0;
2151
2152 if (!sb)
2153 return 0;
2154
2155 switch (cmds) {
2156 case Q_SYNC:
2157 case Q_QUOTAON:
2158 case Q_QUOTAOFF:
2159 case Q_SETINFO:
2160 case Q_SETQUOTA:
2161 case Q_XQUOTAOFF:
2162 case Q_XQUOTAON:
2163 case Q_XSETQLIM:
2164 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2165 break;
2166 case Q_GETFMT:
2167 case Q_GETINFO:
2168 case Q_GETQUOTA:
2169 case Q_XGETQUOTA:
2170 case Q_XGETQSTAT:
2171 case Q_XGETQSTATV:
2172 case Q_XGETNEXTQUOTA:
2173 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2174 break;
2175 default:
2176 rc = 0; /* let the kernel handle invalid cmds */
2177 break;
2178 }
2179 return rc;
2180}
2181
2182static int selinux_quota_on(struct dentry *dentry)
2183{
2184 const struct cred *cred = current_cred();
2185
2186 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2187}
2188
2189static int selinux_syslog(int type)
2190{
2191 switch (type) {
2192 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2193 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2194 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2195 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2196 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2197 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2198 /* Set level of messages printed to console */
2199 case SYSLOG_ACTION_CONSOLE_LEVEL:
2200 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2201 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2202 NULL);
2203 }
2204 /* All other syslog types */
2205 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2206 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2207}
2208
2209/*
2210 * Check permission for allocating a new virtual mapping. Returns
2211 * 0 if permission is granted, negative error code if not.
2212 *
2213 * Do not audit the selinux permission check, as this is applied to all
2214 * processes that allocate mappings.
2215 */
2216static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2217{
2218 return cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2219 CAP_OPT_NOAUDIT, true);
2220}
2221
2222/* binprm security operations */
2223
2224static u32 ptrace_parent_sid(void)
2225{
2226 u32 sid = 0;
2227 struct task_struct *tracer;
2228
2229 rcu_read_lock();
2230 tracer = ptrace_parent(current);
2231 if (tracer)
2232 sid = task_sid_obj(tracer);
2233 rcu_read_unlock();
2234
2235 return sid;
2236}
2237
2238static int check_nnp_nosuid(const struct linux_binprm *bprm,
2239 const struct task_security_struct *old_tsec,
2240 const struct task_security_struct *new_tsec)
2241{
2242 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2243 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2244 int rc;
2245 u32 av;
2246
2247 if (!nnp && !nosuid)
2248 return 0; /* neither NNP nor nosuid */
2249
2250 if (new_tsec->sid == old_tsec->sid)
2251 return 0; /* No change in credentials */
2252
2253 /*
2254 * If the policy enables the nnp_nosuid_transition policy capability,
2255 * then we permit transitions under NNP or nosuid if the
2256 * policy allows the corresponding permission between
2257 * the old and new contexts.
2258 */
2259 if (selinux_policycap_nnp_nosuid_transition()) {
2260 av = 0;
2261 if (nnp)
2262 av |= PROCESS2__NNP_TRANSITION;
2263 if (nosuid)
2264 av |= PROCESS2__NOSUID_TRANSITION;
2265 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2266 SECCLASS_PROCESS2, av, NULL);
2267 if (!rc)
2268 return 0;
2269 }
2270
2271 /*
2272 * We also permit NNP or nosuid transitions to bounded SIDs,
2273 * i.e. SIDs that are guaranteed to only be allowed a subset
2274 * of the permissions of the current SID.
2275 */
2276 rc = security_bounded_transition(old_tsec->sid,
2277 new_tsec->sid);
2278 if (!rc)
2279 return 0;
2280
2281 /*
2282 * On failure, preserve the errno values for NNP vs nosuid.
2283 * NNP: Operation not permitted for caller.
2284 * nosuid: Permission denied to file.
2285 */
2286 if (nnp)
2287 return -EPERM;
2288 return -EACCES;
2289}
2290
2291static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2292{
2293 const struct task_security_struct *old_tsec;
2294 struct task_security_struct *new_tsec;
2295 struct inode_security_struct *isec;
2296 struct common_audit_data ad;
2297 struct inode *inode = file_inode(bprm->file);
2298 int rc;
2299
2300 /* SELinux context only depends on initial program or script and not
2301 * the script interpreter */
2302
2303 old_tsec = selinux_cred(current_cred());
2304 new_tsec = selinux_cred(bprm->cred);
2305 isec = inode_security(inode);
2306
2307 /* Default to the current task SID. */
2308 new_tsec->sid = old_tsec->sid;
2309 new_tsec->osid = old_tsec->sid;
2310
2311 /* Reset fs, key, and sock SIDs on execve. */
2312 new_tsec->create_sid = 0;
2313 new_tsec->keycreate_sid = 0;
2314 new_tsec->sockcreate_sid = 0;
2315
2316 /*
2317 * Before policy is loaded, label any task outside kernel space
2318 * as SECINITSID_INIT, so that any userspace tasks surviving from
2319 * early boot end up with a label different from SECINITSID_KERNEL
2320 * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
2321 */
2322 if (!selinux_initialized()) {
2323 new_tsec->sid = SECINITSID_INIT;
2324 /* also clear the exec_sid just in case */
2325 new_tsec->exec_sid = 0;
2326 return 0;
2327 }
2328
2329 if (old_tsec->exec_sid) {
2330 new_tsec->sid = old_tsec->exec_sid;
2331 /* Reset exec SID on execve. */
2332 new_tsec->exec_sid = 0;
2333
2334 /* Fail on NNP or nosuid if not an allowed transition. */
2335 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2336 if (rc)
2337 return rc;
2338 } else {
2339 /* Check for a default transition on this program. */
2340 rc = security_transition_sid(old_tsec->sid,
2341 isec->sid, SECCLASS_PROCESS, NULL,
2342 &new_tsec->sid);
2343 if (rc)
2344 return rc;
2345
2346 /*
2347 * Fallback to old SID on NNP or nosuid if not an allowed
2348 * transition.
2349 */
2350 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2351 if (rc)
2352 new_tsec->sid = old_tsec->sid;
2353 }
2354
2355 ad.type = LSM_AUDIT_DATA_FILE;
2356 ad.u.file = bprm->file;
2357
2358 if (new_tsec->sid == old_tsec->sid) {
2359 rc = avc_has_perm(old_tsec->sid, isec->sid,
2360 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2361 if (rc)
2362 return rc;
2363 } else {
2364 /* Check permissions for the transition. */
2365 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2366 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2367 if (rc)
2368 return rc;
2369
2370 rc = avc_has_perm(new_tsec->sid, isec->sid,
2371 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2372 if (rc)
2373 return rc;
2374
2375 /* Check for shared state */
2376 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2377 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2378 SECCLASS_PROCESS, PROCESS__SHARE,
2379 NULL);
2380 if (rc)
2381 return -EPERM;
2382 }
2383
2384 /* Make sure that anyone attempting to ptrace over a task that
2385 * changes its SID has the appropriate permit */
2386 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2387 u32 ptsid = ptrace_parent_sid();
2388 if (ptsid != 0) {
2389 rc = avc_has_perm(ptsid, new_tsec->sid,
2390 SECCLASS_PROCESS,
2391 PROCESS__PTRACE, NULL);
2392 if (rc)
2393 return -EPERM;
2394 }
2395 }
2396
2397 /* Clear any possibly unsafe personality bits on exec: */
2398 bprm->per_clear |= PER_CLEAR_ON_SETID;
2399
2400 /* Enable secure mode for SIDs transitions unless
2401 the noatsecure permission is granted between
2402 the two SIDs, i.e. ahp returns 0. */
2403 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2404 SECCLASS_PROCESS, PROCESS__NOATSECURE,
2405 NULL);
2406 bprm->secureexec |= !!rc;
2407 }
2408
2409 return 0;
2410}
2411
2412static int match_file(const void *p, struct file *file, unsigned fd)
2413{
2414 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2415}
2416
2417/* Derived from fs/exec.c:flush_old_files. */
2418static inline void flush_unauthorized_files(const struct cred *cred,
2419 struct files_struct *files)
2420{
2421 struct file *file, *devnull = NULL;
2422 struct tty_struct *tty;
2423 int drop_tty = 0;
2424 unsigned n;
2425
2426 tty = get_current_tty();
2427 if (tty) {
2428 spin_lock(&tty->files_lock);
2429 if (!list_empty(&tty->tty_files)) {
2430 struct tty_file_private *file_priv;
2431
2432 /* Revalidate access to controlling tty.
2433 Use file_path_has_perm on the tty path directly
2434 rather than using file_has_perm, as this particular
2435 open file may belong to another process and we are
2436 only interested in the inode-based check here. */
2437 file_priv = list_first_entry(&tty->tty_files,
2438 struct tty_file_private, list);
2439 file = file_priv->file;
2440 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2441 drop_tty = 1;
2442 }
2443 spin_unlock(&tty->files_lock);
2444 tty_kref_put(tty);
2445 }
2446 /* Reset controlling tty. */
2447 if (drop_tty)
2448 no_tty();
2449
2450 /* Revalidate access to inherited open files. */
2451 n = iterate_fd(files, 0, match_file, cred);
2452 if (!n) /* none found? */
2453 return;
2454
2455 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2456 if (IS_ERR(devnull))
2457 devnull = NULL;
2458 /* replace all the matching ones with this */
2459 do {
2460 replace_fd(n - 1, devnull, 0);
2461 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2462 if (devnull)
2463 fput(devnull);
2464}
2465
2466/*
2467 * Prepare a process for imminent new credential changes due to exec
2468 */
2469static void selinux_bprm_committing_creds(const struct linux_binprm *bprm)
2470{
2471 struct task_security_struct *new_tsec;
2472 struct rlimit *rlim, *initrlim;
2473 int rc, i;
2474
2475 new_tsec = selinux_cred(bprm->cred);
2476 if (new_tsec->sid == new_tsec->osid)
2477 return;
2478
2479 /* Close files for which the new task SID is not authorized. */
2480 flush_unauthorized_files(bprm->cred, current->files);
2481
2482 /* Always clear parent death signal on SID transitions. */
2483 current->pdeath_signal = 0;
2484
2485 /* Check whether the new SID can inherit resource limits from the old
2486 * SID. If not, reset all soft limits to the lower of the current
2487 * task's hard limit and the init task's soft limit.
2488 *
2489 * Note that the setting of hard limits (even to lower them) can be
2490 * controlled by the setrlimit check. The inclusion of the init task's
2491 * soft limit into the computation is to avoid resetting soft limits
2492 * higher than the default soft limit for cases where the default is
2493 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2494 */
2495 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2496 PROCESS__RLIMITINH, NULL);
2497 if (rc) {
2498 /* protect against do_prlimit() */
2499 task_lock(current);
2500 for (i = 0; i < RLIM_NLIMITS; i++) {
2501 rlim = current->signal->rlim + i;
2502 initrlim = init_task.signal->rlim + i;
2503 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2504 }
2505 task_unlock(current);
2506 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2507 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2508 }
2509}
2510
2511/*
2512 * Clean up the process immediately after the installation of new credentials
2513 * due to exec
2514 */
2515static void selinux_bprm_committed_creds(const struct linux_binprm *bprm)
2516{
2517 const struct task_security_struct *tsec = selinux_cred(current_cred());
2518 u32 osid, sid;
2519 int rc;
2520
2521 osid = tsec->osid;
2522 sid = tsec->sid;
2523
2524 if (sid == osid)
2525 return;
2526
2527 /* Check whether the new SID can inherit signal state from the old SID.
2528 * If not, clear itimers to avoid subsequent signal generation and
2529 * flush and unblock signals.
2530 *
2531 * This must occur _after_ the task SID has been updated so that any
2532 * kill done after the flush will be checked against the new SID.
2533 */
2534 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2535 if (rc) {
2536 clear_itimer();
2537
2538 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2539 if (!fatal_signal_pending(current)) {
2540 flush_sigqueue(¤t->pending);
2541 flush_sigqueue(¤t->signal->shared_pending);
2542 flush_signal_handlers(current, 1);
2543 sigemptyset(¤t->blocked);
2544 recalc_sigpending();
2545 }
2546 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2547 }
2548
2549 /* Wake up the parent if it is waiting so that it can recheck
2550 * wait permission to the new task SID. */
2551 read_lock(&tasklist_lock);
2552 __wake_up_parent(current, unrcu_pointer(current->real_parent));
2553 read_unlock(&tasklist_lock);
2554}
2555
2556/* superblock security operations */
2557
2558static int selinux_sb_alloc_security(struct super_block *sb)
2559{
2560 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2561
2562 mutex_init(&sbsec->lock);
2563 INIT_LIST_HEAD(&sbsec->isec_head);
2564 spin_lock_init(&sbsec->isec_lock);
2565 sbsec->sid = SECINITSID_UNLABELED;
2566 sbsec->def_sid = SECINITSID_FILE;
2567 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2568
2569 return 0;
2570}
2571
2572static inline int opt_len(const char *s)
2573{
2574 bool open_quote = false;
2575 int len;
2576 char c;
2577
2578 for (len = 0; (c = s[len]) != '\0'; len++) {
2579 if (c == '"')
2580 open_quote = !open_quote;
2581 if (c == ',' && !open_quote)
2582 break;
2583 }
2584 return len;
2585}
2586
2587static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2588{
2589 char *from = options;
2590 char *to = options;
2591 bool first = true;
2592 int rc;
2593
2594 while (1) {
2595 int len = opt_len(from);
2596 int token;
2597 char *arg = NULL;
2598
2599 token = match_opt_prefix(from, len, &arg);
2600
2601 if (token != Opt_error) {
2602 char *p, *q;
2603
2604 /* strip quotes */
2605 if (arg) {
2606 for (p = q = arg; p < from + len; p++) {
2607 char c = *p;
2608 if (c != '"')
2609 *q++ = c;
2610 }
2611 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2612 if (!arg) {
2613 rc = -ENOMEM;
2614 goto free_opt;
2615 }
2616 }
2617 rc = selinux_add_opt(token, arg, mnt_opts);
2618 kfree(arg);
2619 arg = NULL;
2620 if (unlikely(rc)) {
2621 goto free_opt;
2622 }
2623 } else {
2624 if (!first) { // copy with preceding comma
2625 from--;
2626 len++;
2627 }
2628 if (to != from)
2629 memmove(to, from, len);
2630 to += len;
2631 first = false;
2632 }
2633 if (!from[len])
2634 break;
2635 from += len + 1;
2636 }
2637 *to = '\0';
2638 return 0;
2639
2640free_opt:
2641 if (*mnt_opts) {
2642 selinux_free_mnt_opts(*mnt_opts);
2643 *mnt_opts = NULL;
2644 }
2645 return rc;
2646}
2647
2648static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2649{
2650 struct selinux_mnt_opts *opts = mnt_opts;
2651 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2652
2653 /*
2654 * Superblock not initialized (i.e. no options) - reject if any
2655 * options specified, otherwise accept.
2656 */
2657 if (!(sbsec->flags & SE_SBINITIALIZED))
2658 return opts ? 1 : 0;
2659
2660 /*
2661 * Superblock initialized and no options specified - reject if
2662 * superblock has any options set, otherwise accept.
2663 */
2664 if (!opts)
2665 return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2666
2667 if (opts->fscontext_sid) {
2668 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2669 opts->fscontext_sid))
2670 return 1;
2671 }
2672 if (opts->context_sid) {
2673 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2674 opts->context_sid))
2675 return 1;
2676 }
2677 if (opts->rootcontext_sid) {
2678 struct inode_security_struct *root_isec;
2679
2680 root_isec = backing_inode_security(sb->s_root);
2681 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2682 opts->rootcontext_sid))
2683 return 1;
2684 }
2685 if (opts->defcontext_sid) {
2686 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2687 opts->defcontext_sid))
2688 return 1;
2689 }
2690 return 0;
2691}
2692
2693static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2694{
2695 struct selinux_mnt_opts *opts = mnt_opts;
2696 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2697
2698 if (!(sbsec->flags & SE_SBINITIALIZED))
2699 return 0;
2700
2701 if (!opts)
2702 return 0;
2703
2704 if (opts->fscontext_sid) {
2705 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2706 opts->fscontext_sid))
2707 goto out_bad_option;
2708 }
2709 if (opts->context_sid) {
2710 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2711 opts->context_sid))
2712 goto out_bad_option;
2713 }
2714 if (opts->rootcontext_sid) {
2715 struct inode_security_struct *root_isec;
2716 root_isec = backing_inode_security(sb->s_root);
2717 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2718 opts->rootcontext_sid))
2719 goto out_bad_option;
2720 }
2721 if (opts->defcontext_sid) {
2722 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2723 opts->defcontext_sid))
2724 goto out_bad_option;
2725 }
2726 return 0;
2727
2728out_bad_option:
2729 pr_warn("SELinux: unable to change security options "
2730 "during remount (dev %s, type=%s)\n", sb->s_id,
2731 sb->s_type->name);
2732 return -EINVAL;
2733}
2734
2735static int selinux_sb_kern_mount(const struct super_block *sb)
2736{
2737 const struct cred *cred = current_cred();
2738 struct common_audit_data ad;
2739
2740 ad.type = LSM_AUDIT_DATA_DENTRY;
2741 ad.u.dentry = sb->s_root;
2742 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2743}
2744
2745static int selinux_sb_statfs(struct dentry *dentry)
2746{
2747 const struct cred *cred = current_cred();
2748 struct common_audit_data ad;
2749
2750 ad.type = LSM_AUDIT_DATA_DENTRY;
2751 ad.u.dentry = dentry->d_sb->s_root;
2752 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2753}
2754
2755static int selinux_mount(const char *dev_name,
2756 const struct path *path,
2757 const char *type,
2758 unsigned long flags,
2759 void *data)
2760{
2761 const struct cred *cred = current_cred();
2762
2763 if (flags & MS_REMOUNT)
2764 return superblock_has_perm(cred, path->dentry->d_sb,
2765 FILESYSTEM__REMOUNT, NULL);
2766 else
2767 return path_has_perm(cred, path, FILE__MOUNTON);
2768}
2769
2770static int selinux_move_mount(const struct path *from_path,
2771 const struct path *to_path)
2772{
2773 const struct cred *cred = current_cred();
2774
2775 return path_has_perm(cred, to_path, FILE__MOUNTON);
2776}
2777
2778static int selinux_umount(struct vfsmount *mnt, int flags)
2779{
2780 const struct cred *cred = current_cred();
2781
2782 return superblock_has_perm(cred, mnt->mnt_sb,
2783 FILESYSTEM__UNMOUNT, NULL);
2784}
2785
2786static int selinux_fs_context_submount(struct fs_context *fc,
2787 struct super_block *reference)
2788{
2789 const struct superblock_security_struct *sbsec = selinux_superblock(reference);
2790 struct selinux_mnt_opts *opts;
2791
2792 /*
2793 * Ensure that fc->security remains NULL when no options are set
2794 * as expected by selinux_set_mnt_opts().
2795 */
2796 if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT)))
2797 return 0;
2798
2799 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2800 if (!opts)
2801 return -ENOMEM;
2802
2803 if (sbsec->flags & FSCONTEXT_MNT)
2804 opts->fscontext_sid = sbsec->sid;
2805 if (sbsec->flags & CONTEXT_MNT)
2806 opts->context_sid = sbsec->mntpoint_sid;
2807 if (sbsec->flags & DEFCONTEXT_MNT)
2808 opts->defcontext_sid = sbsec->def_sid;
2809 fc->security = opts;
2810 return 0;
2811}
2812
2813static int selinux_fs_context_dup(struct fs_context *fc,
2814 struct fs_context *src_fc)
2815{
2816 const struct selinux_mnt_opts *src = src_fc->security;
2817
2818 if (!src)
2819 return 0;
2820
2821 fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2822 return fc->security ? 0 : -ENOMEM;
2823}
2824
2825static const struct fs_parameter_spec selinux_fs_parameters[] = {
2826 fsparam_string(CONTEXT_STR, Opt_context),
2827 fsparam_string(DEFCONTEXT_STR, Opt_defcontext),
2828 fsparam_string(FSCONTEXT_STR, Opt_fscontext),
2829 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2830 fsparam_flag (SECLABEL_STR, Opt_seclabel),
2831 {}
2832};
2833
2834static int selinux_fs_context_parse_param(struct fs_context *fc,
2835 struct fs_parameter *param)
2836{
2837 struct fs_parse_result result;
2838 int opt;
2839
2840 opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2841 if (opt < 0)
2842 return opt;
2843
2844 return selinux_add_opt(opt, param->string, &fc->security);
2845}
2846
2847/* inode security operations */
2848
2849static int selinux_inode_alloc_security(struct inode *inode)
2850{
2851 struct inode_security_struct *isec = selinux_inode(inode);
2852 u32 sid = current_sid();
2853
2854 spin_lock_init(&isec->lock);
2855 INIT_LIST_HEAD(&isec->list);
2856 isec->inode = inode;
2857 isec->sid = SECINITSID_UNLABELED;
2858 isec->sclass = SECCLASS_FILE;
2859 isec->task_sid = sid;
2860 isec->initialized = LABEL_INVALID;
2861
2862 return 0;
2863}
2864
2865static void selinux_inode_free_security(struct inode *inode)
2866{
2867 inode_free_security(inode);
2868}
2869
2870static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2871 const struct qstr *name,
2872 const char **xattr_name, void **ctx,
2873 u32 *ctxlen)
2874{
2875 u32 newsid;
2876 int rc;
2877
2878 rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2879 d_inode(dentry->d_parent), name,
2880 inode_mode_to_security_class(mode),
2881 &newsid);
2882 if (rc)
2883 return rc;
2884
2885 if (xattr_name)
2886 *xattr_name = XATTR_NAME_SELINUX;
2887
2888 return security_sid_to_context(newsid, (char **)ctx,
2889 ctxlen);
2890}
2891
2892static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2893 struct qstr *name,
2894 const struct cred *old,
2895 struct cred *new)
2896{
2897 u32 newsid;
2898 int rc;
2899 struct task_security_struct *tsec;
2900
2901 rc = selinux_determine_inode_label(selinux_cred(old),
2902 d_inode(dentry->d_parent), name,
2903 inode_mode_to_security_class(mode),
2904 &newsid);
2905 if (rc)
2906 return rc;
2907
2908 tsec = selinux_cred(new);
2909 tsec->create_sid = newsid;
2910 return 0;
2911}
2912
2913static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2914 const struct qstr *qstr,
2915 struct xattr *xattrs, int *xattr_count)
2916{
2917 const struct task_security_struct *tsec = selinux_cred(current_cred());
2918 struct superblock_security_struct *sbsec;
2919 struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
2920 u32 newsid, clen;
2921 u16 newsclass;
2922 int rc;
2923 char *context;
2924
2925 sbsec = selinux_superblock(dir->i_sb);
2926
2927 newsid = tsec->create_sid;
2928 newsclass = inode_mode_to_security_class(inode->i_mode);
2929 rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid);
2930 if (rc)
2931 return rc;
2932
2933 /* Possibly defer initialization to selinux_complete_init. */
2934 if (sbsec->flags & SE_SBINITIALIZED) {
2935 struct inode_security_struct *isec = selinux_inode(inode);
2936 isec->sclass = newsclass;
2937 isec->sid = newsid;
2938 isec->initialized = LABEL_INITIALIZED;
2939 }
2940
2941 if (!selinux_initialized() ||
2942 !(sbsec->flags & SBLABEL_MNT))
2943 return -EOPNOTSUPP;
2944
2945 if (xattr) {
2946 rc = security_sid_to_context_force(newsid,
2947 &context, &clen);
2948 if (rc)
2949 return rc;
2950 xattr->value = context;
2951 xattr->value_len = clen;
2952 xattr->name = XATTR_SELINUX_SUFFIX;
2953 }
2954
2955 return 0;
2956}
2957
2958static int selinux_inode_init_security_anon(struct inode *inode,
2959 const struct qstr *name,
2960 const struct inode *context_inode)
2961{
2962 u32 sid = current_sid();
2963 struct common_audit_data ad;
2964 struct inode_security_struct *isec;
2965 int rc;
2966
2967 if (unlikely(!selinux_initialized()))
2968 return 0;
2969
2970 isec = selinux_inode(inode);
2971
2972 /*
2973 * We only get here once per ephemeral inode. The inode has
2974 * been initialized via inode_alloc_security but is otherwise
2975 * untouched.
2976 */
2977
2978 if (context_inode) {
2979 struct inode_security_struct *context_isec =
2980 selinux_inode(context_inode);
2981 if (context_isec->initialized != LABEL_INITIALIZED) {
2982 pr_err("SELinux: context_inode is not initialized\n");
2983 return -EACCES;
2984 }
2985
2986 isec->sclass = context_isec->sclass;
2987 isec->sid = context_isec->sid;
2988 } else {
2989 isec->sclass = SECCLASS_ANON_INODE;
2990 rc = security_transition_sid(
2991 sid, sid,
2992 isec->sclass, name, &isec->sid);
2993 if (rc)
2994 return rc;
2995 }
2996
2997 isec->initialized = LABEL_INITIALIZED;
2998 /*
2999 * Now that we've initialized security, check whether we're
3000 * allowed to actually create this type of anonymous inode.
3001 */
3002
3003 ad.type = LSM_AUDIT_DATA_ANONINODE;
3004 ad.u.anonclass = name ? (const char *)name->name : "?";
3005
3006 return avc_has_perm(sid,
3007 isec->sid,
3008 isec->sclass,
3009 FILE__CREATE,
3010 &ad);
3011}
3012
3013static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3014{
3015 return may_create(dir, dentry, SECCLASS_FILE);
3016}
3017
3018static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3019{
3020 return may_link(dir, old_dentry, MAY_LINK);
3021}
3022
3023static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3024{
3025 return may_link(dir, dentry, MAY_UNLINK);
3026}
3027
3028static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3029{
3030 return may_create(dir, dentry, SECCLASS_LNK_FILE);
3031}
3032
3033static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3034{
3035 return may_create(dir, dentry, SECCLASS_DIR);
3036}
3037
3038static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3039{
3040 return may_link(dir, dentry, MAY_RMDIR);
3041}
3042
3043static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3044{
3045 return may_create(dir, dentry, inode_mode_to_security_class(mode));
3046}
3047
3048static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3049 struct inode *new_inode, struct dentry *new_dentry)
3050{
3051 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3052}
3053
3054static int selinux_inode_readlink(struct dentry *dentry)
3055{
3056 const struct cred *cred = current_cred();
3057
3058 return dentry_has_perm(cred, dentry, FILE__READ);
3059}
3060
3061static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3062 bool rcu)
3063{
3064 struct common_audit_data ad;
3065 struct inode_security_struct *isec;
3066 u32 sid = current_sid();
3067
3068 ad.type = LSM_AUDIT_DATA_DENTRY;
3069 ad.u.dentry = dentry;
3070 isec = inode_security_rcu(inode, rcu);
3071 if (IS_ERR(isec))
3072 return PTR_ERR(isec);
3073
3074 return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
3075}
3076
3077static noinline int audit_inode_permission(struct inode *inode,
3078 u32 perms, u32 audited, u32 denied,
3079 int result)
3080{
3081 struct common_audit_data ad;
3082 struct inode_security_struct *isec = selinux_inode(inode);
3083
3084 ad.type = LSM_AUDIT_DATA_INODE;
3085 ad.u.inode = inode;
3086
3087 return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3088 audited, denied, result, &ad);
3089}
3090
3091static int selinux_inode_permission(struct inode *inode, int mask)
3092{
3093 u32 perms;
3094 bool from_access;
3095 bool no_block = mask & MAY_NOT_BLOCK;
3096 struct inode_security_struct *isec;
3097 u32 sid = current_sid();
3098 struct av_decision avd;
3099 int rc, rc2;
3100 u32 audited, denied;
3101
3102 from_access = mask & MAY_ACCESS;
3103 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3104
3105 /* No permission to check. Existence test. */
3106 if (!mask)
3107 return 0;
3108
3109 if (unlikely(IS_PRIVATE(inode)))
3110 return 0;
3111
3112 perms = file_mask_to_av(inode->i_mode, mask);
3113
3114 isec = inode_security_rcu(inode, no_block);
3115 if (IS_ERR(isec))
3116 return PTR_ERR(isec);
3117
3118 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
3119 &avd);
3120 audited = avc_audit_required(perms, &avd, rc,
3121 from_access ? FILE__AUDIT_ACCESS : 0,
3122 &denied);
3123 if (likely(!audited))
3124 return rc;
3125
3126 rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3127 if (rc2)
3128 return rc2;
3129 return rc;
3130}
3131
3132static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
3133 struct iattr *iattr)
3134{
3135 const struct cred *cred = current_cred();
3136 struct inode *inode = d_backing_inode(dentry);
3137 unsigned int ia_valid = iattr->ia_valid;
3138 __u32 av = FILE__WRITE;
3139
3140 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3141 if (ia_valid & ATTR_FORCE) {
3142 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3143 ATTR_FORCE);
3144 if (!ia_valid)
3145 return 0;
3146 }
3147
3148 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3149 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3150 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3151
3152 if (selinux_policycap_openperm() &&
3153 inode->i_sb->s_magic != SOCKFS_MAGIC &&
3154 (ia_valid & ATTR_SIZE) &&
3155 !(ia_valid & ATTR_FILE))
3156 av |= FILE__OPEN;
3157
3158 return dentry_has_perm(cred, dentry, av);
3159}
3160
3161static int selinux_inode_getattr(const struct path *path)
3162{
3163 return path_has_perm(current_cred(), path, FILE__GETATTR);
3164}
3165
3166static bool has_cap_mac_admin(bool audit)
3167{
3168 const struct cred *cred = current_cred();
3169 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3170
3171 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3172 return false;
3173 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3174 return false;
3175 return true;
3176}
3177
3178/**
3179 * selinux_inode_xattr_skipcap - Skip the xattr capability checks?
3180 * @name: name of the xattr
3181 *
3182 * Returns 1 to indicate that SELinux "owns" the access control rights to xattrs
3183 * named @name; the LSM layer should avoid enforcing any traditional
3184 * capability based access controls on this xattr. Returns 0 to indicate that
3185 * SELinux does not "own" the access control rights to xattrs named @name and is
3186 * deferring to the LSM layer for further access controls, including capability
3187 * based controls.
3188 */
3189static int selinux_inode_xattr_skipcap(const char *name)
3190{
3191 /* require capability check if not a selinux xattr */
3192 return !strcmp(name, XATTR_NAME_SELINUX);
3193}
3194
3195static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3196 struct dentry *dentry, const char *name,
3197 const void *value, size_t size, int flags)
3198{
3199 struct inode *inode = d_backing_inode(dentry);
3200 struct inode_security_struct *isec;
3201 struct superblock_security_struct *sbsec;
3202 struct common_audit_data ad;
3203 u32 newsid, sid = current_sid();
3204 int rc = 0;
3205
3206 /* if not a selinux xattr, only check the ordinary setattr perm */
3207 if (strcmp(name, XATTR_NAME_SELINUX))
3208 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3209
3210 if (!selinux_initialized())
3211 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3212
3213 sbsec = selinux_superblock(inode->i_sb);
3214 if (!(sbsec->flags & SBLABEL_MNT))
3215 return -EOPNOTSUPP;
3216
3217 if (!inode_owner_or_capable(idmap, inode))
3218 return -EPERM;
3219
3220 ad.type = LSM_AUDIT_DATA_DENTRY;
3221 ad.u.dentry = dentry;
3222
3223 isec = backing_inode_security(dentry);
3224 rc = avc_has_perm(sid, isec->sid, isec->sclass,
3225 FILE__RELABELFROM, &ad);
3226 if (rc)
3227 return rc;
3228
3229 rc = security_context_to_sid(value, size, &newsid,
3230 GFP_KERNEL);
3231 if (rc == -EINVAL) {
3232 if (!has_cap_mac_admin(true)) {
3233 struct audit_buffer *ab;
3234 size_t audit_size;
3235
3236 /* We strip a nul only if it is at the end, otherwise the
3237 * context contains a nul and we should audit that */
3238 if (value) {
3239 const char *str = value;
3240
3241 if (str[size - 1] == '\0')
3242 audit_size = size - 1;
3243 else
3244 audit_size = size;
3245 } else {
3246 audit_size = 0;
3247 }
3248 ab = audit_log_start(audit_context(),
3249 GFP_ATOMIC, AUDIT_SELINUX_ERR);
3250 if (!ab)
3251 return rc;
3252 audit_log_format(ab, "op=setxattr invalid_context=");
3253 audit_log_n_untrustedstring(ab, value, audit_size);
3254 audit_log_end(ab);
3255
3256 return rc;
3257 }
3258 rc = security_context_to_sid_force(value,
3259 size, &newsid);
3260 }
3261 if (rc)
3262 return rc;
3263
3264 rc = avc_has_perm(sid, newsid, isec->sclass,
3265 FILE__RELABELTO, &ad);
3266 if (rc)
3267 return rc;
3268
3269 rc = security_validate_transition(isec->sid, newsid,
3270 sid, isec->sclass);
3271 if (rc)
3272 return rc;
3273
3274 return avc_has_perm(newsid,
3275 sbsec->sid,
3276 SECCLASS_FILESYSTEM,
3277 FILESYSTEM__ASSOCIATE,
3278 &ad);
3279}
3280
3281static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3282 struct dentry *dentry, const char *acl_name,
3283 struct posix_acl *kacl)
3284{
3285 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3286}
3287
3288static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3289 struct dentry *dentry, const char *acl_name)
3290{
3291 return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3292}
3293
3294static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3295 struct dentry *dentry, const char *acl_name)
3296{
3297 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3298}
3299
3300static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3301 const void *value, size_t size,
3302 int flags)
3303{
3304 struct inode *inode = d_backing_inode(dentry);
3305 struct inode_security_struct *isec;
3306 u32 newsid;
3307 int rc;
3308
3309 if (strcmp(name, XATTR_NAME_SELINUX)) {
3310 /* Not an attribute we recognize, so nothing to do. */
3311 return;
3312 }
3313
3314 if (!selinux_initialized()) {
3315 /* If we haven't even been initialized, then we can't validate
3316 * against a policy, so leave the label as invalid. It may
3317 * resolve to a valid label on the next revalidation try if
3318 * we've since initialized.
3319 */
3320 return;
3321 }
3322
3323 rc = security_context_to_sid_force(value, size,
3324 &newsid);
3325 if (rc) {
3326 pr_err("SELinux: unable to map context to SID"
3327 "for (%s, %lu), rc=%d\n",
3328 inode->i_sb->s_id, inode->i_ino, -rc);
3329 return;
3330 }
3331
3332 isec = backing_inode_security(dentry);
3333 spin_lock(&isec->lock);
3334 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3335 isec->sid = newsid;
3336 isec->initialized = LABEL_INITIALIZED;
3337 spin_unlock(&isec->lock);
3338}
3339
3340static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3341{
3342 const struct cred *cred = current_cred();
3343
3344 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3345}
3346
3347static int selinux_inode_listxattr(struct dentry *dentry)
3348{
3349 const struct cred *cred = current_cred();
3350
3351 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3352}
3353
3354static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3355 struct dentry *dentry, const char *name)
3356{
3357 /* if not a selinux xattr, only check the ordinary setattr perm */
3358 if (strcmp(name, XATTR_NAME_SELINUX))
3359 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3360
3361 if (!selinux_initialized())
3362 return 0;
3363
3364 /* No one is allowed to remove a SELinux security label.
3365 You can change the label, but all data must be labeled. */
3366 return -EACCES;
3367}
3368
3369static int selinux_path_notify(const struct path *path, u64 mask,
3370 unsigned int obj_type)
3371{
3372 int ret;
3373 u32 perm;
3374
3375 struct common_audit_data ad;
3376
3377 ad.type = LSM_AUDIT_DATA_PATH;
3378 ad.u.path = *path;
3379
3380 /*
3381 * Set permission needed based on the type of mark being set.
3382 * Performs an additional check for sb watches.
3383 */
3384 switch (obj_type) {
3385 case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3386 perm = FILE__WATCH_MOUNT;
3387 break;
3388 case FSNOTIFY_OBJ_TYPE_SB:
3389 perm = FILE__WATCH_SB;
3390 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3391 FILESYSTEM__WATCH, &ad);
3392 if (ret)
3393 return ret;
3394 break;
3395 case FSNOTIFY_OBJ_TYPE_INODE:
3396 perm = FILE__WATCH;
3397 break;
3398 default:
3399 return -EINVAL;
3400 }
3401
3402 /* blocking watches require the file:watch_with_perm permission */
3403 if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3404 perm |= FILE__WATCH_WITH_PERM;
3405
3406 /* watches on read-like events need the file:watch_reads permission */
3407 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3408 perm |= FILE__WATCH_READS;
3409
3410 return path_has_perm(current_cred(), path, perm);
3411}
3412
3413/*
3414 * Copy the inode security context value to the user.
3415 *
3416 * Permission check is handled by selinux_inode_getxattr hook.
3417 */
3418static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3419 struct inode *inode, const char *name,
3420 void **buffer, bool alloc)
3421{
3422 u32 size;
3423 int error;
3424 char *context = NULL;
3425 struct inode_security_struct *isec;
3426
3427 /*
3428 * If we're not initialized yet, then we can't validate contexts, so
3429 * just let vfs_getxattr fall back to using the on-disk xattr.
3430 */
3431 if (!selinux_initialized() ||
3432 strcmp(name, XATTR_SELINUX_SUFFIX))
3433 return -EOPNOTSUPP;
3434
3435 /*
3436 * If the caller has CAP_MAC_ADMIN, then get the raw context
3437 * value even if it is not defined by current policy; otherwise,
3438 * use the in-core value under current policy.
3439 * Use the non-auditing forms of the permission checks since
3440 * getxattr may be called by unprivileged processes commonly
3441 * and lack of permission just means that we fall back to the
3442 * in-core context value, not a denial.
3443 */
3444 isec = inode_security(inode);
3445 if (has_cap_mac_admin(false))
3446 error = security_sid_to_context_force(isec->sid, &context,
3447 &size);
3448 else
3449 error = security_sid_to_context(isec->sid,
3450 &context, &size);
3451 if (error)
3452 return error;
3453 error = size;
3454 if (alloc) {
3455 *buffer = context;
3456 goto out_nofree;
3457 }
3458 kfree(context);
3459out_nofree:
3460 return error;
3461}
3462
3463static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3464 const void *value, size_t size, int flags)
3465{
3466 struct inode_security_struct *isec = inode_security_novalidate(inode);
3467 struct superblock_security_struct *sbsec;
3468 u32 newsid;
3469 int rc;
3470
3471 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3472 return -EOPNOTSUPP;
3473
3474 sbsec = selinux_superblock(inode->i_sb);
3475 if (!(sbsec->flags & SBLABEL_MNT))
3476 return -EOPNOTSUPP;
3477
3478 if (!value || !size)
3479 return -EACCES;
3480
3481 rc = security_context_to_sid(value, size, &newsid,
3482 GFP_KERNEL);
3483 if (rc)
3484 return rc;
3485
3486 spin_lock(&isec->lock);
3487 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3488 isec->sid = newsid;
3489 isec->initialized = LABEL_INITIALIZED;
3490 spin_unlock(&isec->lock);
3491 return 0;
3492}
3493
3494static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3495{
3496 const int len = sizeof(XATTR_NAME_SELINUX);
3497
3498 if (!selinux_initialized())
3499 return 0;
3500
3501 if (buffer && len <= buffer_size)
3502 memcpy(buffer, XATTR_NAME_SELINUX, len);
3503 return len;
3504}
3505
3506static void selinux_inode_getlsmprop(struct inode *inode, struct lsm_prop *prop)
3507{
3508 struct inode_security_struct *isec = inode_security_novalidate(inode);
3509
3510 prop->selinux.secid = isec->sid;
3511}
3512
3513static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3514{
3515 struct lsm_prop prop;
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_getlsmprop(d_inode(src), &prop);
3528 tsec->create_sid = prop.selinux.secid;
3529 *new = new_creds;
3530 return 0;
3531}
3532
3533static int selinux_inode_copy_up_xattr(struct dentry *dentry, 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, filter out SELinux-related xattrs following
3538 * policy load.
3539 */
3540 if (selinux_initialized() && !strcmp(name, XATTR_NAME_SELINUX))
3541 return -ECANCELED; /* Discard */
3542 /*
3543 * Any other attribute apart from SELINUX is not claimed, supported
3544 * by selinux.
3545 */
3546 return -EOPNOTSUPP;
3547}
3548
3549/* kernfs node operations */
3550
3551static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3552 struct kernfs_node *kn)
3553{
3554 const struct task_security_struct *tsec = selinux_cred(current_cred());
3555 u32 parent_sid, newsid, clen;
3556 int rc;
3557 char *context;
3558
3559 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3560 if (rc == -ENODATA)
3561 return 0;
3562 else if (rc < 0)
3563 return rc;
3564
3565 clen = (u32)rc;
3566 context = kmalloc(clen, GFP_KERNEL);
3567 if (!context)
3568 return -ENOMEM;
3569
3570 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3571 if (rc < 0) {
3572 kfree(context);
3573 return rc;
3574 }
3575
3576 rc = security_context_to_sid(context, clen, &parent_sid,
3577 GFP_KERNEL);
3578 kfree(context);
3579 if (rc)
3580 return rc;
3581
3582 if (tsec->create_sid) {
3583 newsid = tsec->create_sid;
3584 } else {
3585 u16 secclass = inode_mode_to_security_class(kn->mode);
3586 struct qstr q;
3587
3588 q.name = kn->name;
3589 q.hash_len = hashlen_string(kn_dir, kn->name);
3590
3591 rc = security_transition_sid(tsec->sid,
3592 parent_sid, secclass, &q,
3593 &newsid);
3594 if (rc)
3595 return rc;
3596 }
3597
3598 rc = security_sid_to_context_force(newsid,
3599 &context, &clen);
3600 if (rc)
3601 return rc;
3602
3603 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3604 XATTR_CREATE);
3605 kfree(context);
3606 return rc;
3607}
3608
3609
3610/* file security operations */
3611
3612static int selinux_revalidate_file_permission(struct file *file, int mask)
3613{
3614 const struct cred *cred = current_cred();
3615 struct inode *inode = file_inode(file);
3616
3617 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3618 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3619 mask |= MAY_APPEND;
3620
3621 return file_has_perm(cred, file,
3622 file_mask_to_av(inode->i_mode, mask));
3623}
3624
3625static int selinux_file_permission(struct file *file, int mask)
3626{
3627 struct inode *inode = file_inode(file);
3628 struct file_security_struct *fsec = selinux_file(file);
3629 struct inode_security_struct *isec;
3630 u32 sid = current_sid();
3631
3632 if (!mask)
3633 /* No permission to check. Existence test. */
3634 return 0;
3635
3636 isec = inode_security(inode);
3637 if (sid == fsec->sid && fsec->isid == isec->sid &&
3638 fsec->pseqno == avc_policy_seqno())
3639 /* No change since file_open check. */
3640 return 0;
3641
3642 return selinux_revalidate_file_permission(file, mask);
3643}
3644
3645static int selinux_file_alloc_security(struct file *file)
3646{
3647 struct file_security_struct *fsec = selinux_file(file);
3648 u32 sid = current_sid();
3649
3650 fsec->sid = sid;
3651 fsec->fown_sid = sid;
3652
3653 return 0;
3654}
3655
3656/*
3657 * Check whether a task has the ioctl permission and cmd
3658 * operation to an inode.
3659 */
3660static int ioctl_has_perm(const struct cred *cred, struct file *file,
3661 u32 requested, u16 cmd)
3662{
3663 struct common_audit_data ad;
3664 struct file_security_struct *fsec = selinux_file(file);
3665 struct inode *inode = file_inode(file);
3666 struct inode_security_struct *isec;
3667 struct lsm_ioctlop_audit ioctl;
3668 u32 ssid = cred_sid(cred);
3669 int rc;
3670 u8 driver = cmd >> 8;
3671 u8 xperm = cmd & 0xff;
3672
3673 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3674 ad.u.op = &ioctl;
3675 ad.u.op->cmd = cmd;
3676 ad.u.op->path = file->f_path;
3677
3678 if (ssid != fsec->sid) {
3679 rc = avc_has_perm(ssid, fsec->sid,
3680 SECCLASS_FD,
3681 FD__USE,
3682 &ad);
3683 if (rc)
3684 goto out;
3685 }
3686
3687 if (unlikely(IS_PRIVATE(inode)))
3688 return 0;
3689
3690 isec = inode_security(inode);
3691 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass, requested,
3692 driver, AVC_EXT_IOCTL, xperm, &ad);
3693out:
3694 return rc;
3695}
3696
3697static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3698 unsigned long arg)
3699{
3700 const struct cred *cred = current_cred();
3701 int error = 0;
3702
3703 switch (cmd) {
3704 case FIONREAD:
3705 case FIBMAP:
3706 case FIGETBSZ:
3707 case FS_IOC_GETFLAGS:
3708 case FS_IOC_GETVERSION:
3709 error = file_has_perm(cred, file, FILE__GETATTR);
3710 break;
3711
3712 case FS_IOC_SETFLAGS:
3713 case FS_IOC_SETVERSION:
3714 error = file_has_perm(cred, file, FILE__SETATTR);
3715 break;
3716
3717 /* sys_ioctl() checks */
3718 case FIONBIO:
3719 case FIOASYNC:
3720 error = file_has_perm(cred, file, 0);
3721 break;
3722
3723 case KDSKBENT:
3724 case KDSKBSENT:
3725 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3726 CAP_OPT_NONE, true);
3727 break;
3728
3729 case FIOCLEX:
3730 case FIONCLEX:
3731 if (!selinux_policycap_ioctl_skip_cloexec())
3732 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3733 break;
3734
3735 /* default case assumes that the command will go
3736 * to the file's ioctl() function.
3737 */
3738 default:
3739 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3740 }
3741 return error;
3742}
3743
3744static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3745 unsigned long arg)
3746{
3747 /*
3748 * If we are in a 64-bit kernel running 32-bit userspace, we need to
3749 * make sure we don't compare 32-bit flags to 64-bit flags.
3750 */
3751 switch (cmd) {
3752 case FS_IOC32_GETFLAGS:
3753 cmd = FS_IOC_GETFLAGS;
3754 break;
3755 case FS_IOC32_SETFLAGS:
3756 cmd = FS_IOC_SETFLAGS;
3757 break;
3758 case FS_IOC32_GETVERSION:
3759 cmd = FS_IOC_GETVERSION;
3760 break;
3761 case FS_IOC32_SETVERSION:
3762 cmd = FS_IOC_SETVERSION;
3763 break;
3764 default:
3765 break;
3766 }
3767
3768 return selinux_file_ioctl(file, cmd, arg);
3769}
3770
3771static int default_noexec __ro_after_init;
3772
3773static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3774{
3775 const struct cred *cred = current_cred();
3776 u32 sid = cred_sid(cred);
3777 int rc = 0;
3778
3779 if (default_noexec &&
3780 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3781 (!shared && (prot & PROT_WRITE)))) {
3782 /*
3783 * We are making executable an anonymous mapping or a
3784 * private file mapping that will also be writable.
3785 * This has an additional check.
3786 */
3787 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3788 PROCESS__EXECMEM, NULL);
3789 if (rc)
3790 goto error;
3791 }
3792
3793 if (file) {
3794 /* read access is always possible with a mapping */
3795 u32 av = FILE__READ;
3796
3797 /* write access only matters if the mapping is shared */
3798 if (shared && (prot & PROT_WRITE))
3799 av |= FILE__WRITE;
3800
3801 if (prot & PROT_EXEC)
3802 av |= FILE__EXECUTE;
3803
3804 return file_has_perm(cred, file, av);
3805 }
3806
3807error:
3808 return rc;
3809}
3810
3811static int selinux_mmap_addr(unsigned long addr)
3812{
3813 int rc = 0;
3814
3815 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3816 u32 sid = current_sid();
3817 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3818 MEMPROTECT__MMAP_ZERO, NULL);
3819 }
3820
3821 return rc;
3822}
3823
3824static int selinux_mmap_file(struct file *file,
3825 unsigned long reqprot __always_unused,
3826 unsigned long prot, unsigned long flags)
3827{
3828 struct common_audit_data ad;
3829 int rc;
3830
3831 if (file) {
3832 ad.type = LSM_AUDIT_DATA_FILE;
3833 ad.u.file = file;
3834 rc = inode_has_perm(current_cred(), file_inode(file),
3835 FILE__MAP, &ad);
3836 if (rc)
3837 return rc;
3838 }
3839
3840 return file_map_prot_check(file, prot,
3841 (flags & MAP_TYPE) == MAP_SHARED);
3842}
3843
3844static int selinux_file_mprotect(struct vm_area_struct *vma,
3845 unsigned long reqprot __always_unused,
3846 unsigned long prot)
3847{
3848 const struct cred *cred = current_cred();
3849 u32 sid = cred_sid(cred);
3850
3851 if (default_noexec &&
3852 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3853 int rc = 0;
3854 /*
3855 * We don't use the vma_is_initial_heap() helper as it has
3856 * a history of problems and is currently broken on systems
3857 * where there is no heap, e.g. brk == start_brk. Before
3858 * replacing the conditional below with vma_is_initial_heap(),
3859 * or something similar, please ensure that the logic is the
3860 * same as what we have below or you have tested every possible
3861 * corner case you can think to test.
3862 */
3863 if (vma->vm_start >= vma->vm_mm->start_brk &&
3864 vma->vm_end <= vma->vm_mm->brk) {
3865 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3866 PROCESS__EXECHEAP, NULL);
3867 } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3868 vma_is_stack_for_current(vma))) {
3869 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3870 PROCESS__EXECSTACK, NULL);
3871 } else if (vma->vm_file && vma->anon_vma) {
3872 /*
3873 * We are making executable a file mapping that has
3874 * had some COW done. Since pages might have been
3875 * written, check ability to execute the possibly
3876 * modified content. This typically should only
3877 * occur for text relocations.
3878 */
3879 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3880 }
3881 if (rc)
3882 return rc;
3883 }
3884
3885 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3886}
3887
3888static int selinux_file_lock(struct file *file, unsigned int cmd)
3889{
3890 const struct cred *cred = current_cred();
3891
3892 return file_has_perm(cred, file, FILE__LOCK);
3893}
3894
3895static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3896 unsigned long arg)
3897{
3898 const struct cred *cred = current_cred();
3899 int err = 0;
3900
3901 switch (cmd) {
3902 case F_SETFL:
3903 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3904 err = file_has_perm(cred, file, FILE__WRITE);
3905 break;
3906 }
3907 fallthrough;
3908 case F_SETOWN:
3909 case F_SETSIG:
3910 case F_GETFL:
3911 case F_GETOWN:
3912 case F_GETSIG:
3913 case F_GETOWNER_UIDS:
3914 /* Just check FD__USE permission */
3915 err = file_has_perm(cred, file, 0);
3916 break;
3917 case F_GETLK:
3918 case F_SETLK:
3919 case F_SETLKW:
3920 case F_OFD_GETLK:
3921 case F_OFD_SETLK:
3922 case F_OFD_SETLKW:
3923#if BITS_PER_LONG == 32
3924 case F_GETLK64:
3925 case F_SETLK64:
3926 case F_SETLKW64:
3927#endif
3928 err = file_has_perm(cred, file, FILE__LOCK);
3929 break;
3930 }
3931
3932 return err;
3933}
3934
3935static void selinux_file_set_fowner(struct file *file)
3936{
3937 struct file_security_struct *fsec;
3938
3939 fsec = selinux_file(file);
3940 fsec->fown_sid = current_sid();
3941}
3942
3943static int selinux_file_send_sigiotask(struct task_struct *tsk,
3944 struct fown_struct *fown, int signum)
3945{
3946 struct file *file;
3947 u32 sid = task_sid_obj(tsk);
3948 u32 perm;
3949 struct file_security_struct *fsec;
3950
3951 /* struct fown_struct is never outside the context of a struct file */
3952 file = fown->file;
3953
3954 fsec = selinux_file(file);
3955
3956 if (!signum)
3957 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3958 else
3959 perm = signal_to_av(signum);
3960
3961 return avc_has_perm(fsec->fown_sid, sid,
3962 SECCLASS_PROCESS, perm, NULL);
3963}
3964
3965static int selinux_file_receive(struct file *file)
3966{
3967 const struct cred *cred = current_cred();
3968
3969 return file_has_perm(cred, file, file_to_av(file));
3970}
3971
3972static int selinux_file_open(struct file *file)
3973{
3974 struct file_security_struct *fsec;
3975 struct inode_security_struct *isec;
3976
3977 fsec = selinux_file(file);
3978 isec = inode_security(file_inode(file));
3979 /*
3980 * Save inode label and policy sequence number
3981 * at open-time so that selinux_file_permission
3982 * can determine whether revalidation is necessary.
3983 * Task label is already saved in the file security
3984 * struct as its SID.
3985 */
3986 fsec->isid = isec->sid;
3987 fsec->pseqno = avc_policy_seqno();
3988 /*
3989 * Since the inode label or policy seqno may have changed
3990 * between the selinux_inode_permission check and the saving
3991 * of state above, recheck that access is still permitted.
3992 * Otherwise, access might never be revalidated against the
3993 * new inode label or new policy.
3994 * This check is not redundant - do not remove.
3995 */
3996 return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3997}
3998
3999/* task security operations */
4000
4001static int selinux_task_alloc(struct task_struct *task,
4002 unsigned long clone_flags)
4003{
4004 u32 sid = current_sid();
4005
4006 return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
4007}
4008
4009/*
4010 * prepare a new set of credentials for modification
4011 */
4012static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4013 gfp_t gfp)
4014{
4015 const struct task_security_struct *old_tsec = selinux_cred(old);
4016 struct task_security_struct *tsec = selinux_cred(new);
4017
4018 *tsec = *old_tsec;
4019 return 0;
4020}
4021
4022/*
4023 * transfer the SELinux data to a blank set of creds
4024 */
4025static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4026{
4027 const struct task_security_struct *old_tsec = selinux_cred(old);
4028 struct task_security_struct *tsec = selinux_cred(new);
4029
4030 *tsec = *old_tsec;
4031}
4032
4033static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4034{
4035 *secid = cred_sid(c);
4036}
4037
4038static void selinux_cred_getlsmprop(const struct cred *c, struct lsm_prop *prop)
4039{
4040 prop->selinux.secid = cred_sid(c);
4041}
4042
4043/*
4044 * set the security data for a kernel service
4045 * - all the creation contexts are set to unlabelled
4046 */
4047static int selinux_kernel_act_as(struct cred *new, u32 secid)
4048{
4049 struct task_security_struct *tsec = selinux_cred(new);
4050 u32 sid = current_sid();
4051 int ret;
4052
4053 ret = avc_has_perm(sid, secid,
4054 SECCLASS_KERNEL_SERVICE,
4055 KERNEL_SERVICE__USE_AS_OVERRIDE,
4056 NULL);
4057 if (ret == 0) {
4058 tsec->sid = secid;
4059 tsec->create_sid = 0;
4060 tsec->keycreate_sid = 0;
4061 tsec->sockcreate_sid = 0;
4062 }
4063 return ret;
4064}
4065
4066/*
4067 * set the file creation context in a security record to the same as the
4068 * objective context of the specified inode
4069 */
4070static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4071{
4072 struct inode_security_struct *isec = inode_security(inode);
4073 struct task_security_struct *tsec = selinux_cred(new);
4074 u32 sid = current_sid();
4075 int ret;
4076
4077 ret = avc_has_perm(sid, isec->sid,
4078 SECCLASS_KERNEL_SERVICE,
4079 KERNEL_SERVICE__CREATE_FILES_AS,
4080 NULL);
4081
4082 if (ret == 0)
4083 tsec->create_sid = isec->sid;
4084 return ret;
4085}
4086
4087static int selinux_kernel_module_request(char *kmod_name)
4088{
4089 struct common_audit_data ad;
4090
4091 ad.type = LSM_AUDIT_DATA_KMOD;
4092 ad.u.kmod_name = kmod_name;
4093
4094 return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4095 SYSTEM__MODULE_REQUEST, &ad);
4096}
4097
4098static int selinux_kernel_module_from_file(struct file *file)
4099{
4100 struct common_audit_data ad;
4101 struct inode_security_struct *isec;
4102 struct file_security_struct *fsec;
4103 u32 sid = current_sid();
4104 int rc;
4105
4106 /* init_module */
4107 if (file == NULL)
4108 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4109 SYSTEM__MODULE_LOAD, NULL);
4110
4111 /* finit_module */
4112
4113 ad.type = LSM_AUDIT_DATA_FILE;
4114 ad.u.file = file;
4115
4116 fsec = selinux_file(file);
4117 if (sid != fsec->sid) {
4118 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4119 if (rc)
4120 return rc;
4121 }
4122
4123 isec = inode_security(file_inode(file));
4124 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4125 SYSTEM__MODULE_LOAD, &ad);
4126}
4127
4128static int selinux_kernel_read_file(struct file *file,
4129 enum kernel_read_file_id id,
4130 bool contents)
4131{
4132 int rc = 0;
4133
4134 switch (id) {
4135 case READING_MODULE:
4136 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4137 break;
4138 default:
4139 break;
4140 }
4141
4142 return rc;
4143}
4144
4145static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4146{
4147 int rc = 0;
4148
4149 switch (id) {
4150 case LOADING_MODULE:
4151 rc = selinux_kernel_module_from_file(NULL);
4152 break;
4153 default:
4154 break;
4155 }
4156
4157 return rc;
4158}
4159
4160static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4161{
4162 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4163 PROCESS__SETPGID, NULL);
4164}
4165
4166static int selinux_task_getpgid(struct task_struct *p)
4167{
4168 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4169 PROCESS__GETPGID, NULL);
4170}
4171
4172static int selinux_task_getsid(struct task_struct *p)
4173{
4174 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4175 PROCESS__GETSESSION, NULL);
4176}
4177
4178static void selinux_current_getlsmprop_subj(struct lsm_prop *prop)
4179{
4180 prop->selinux.secid = current_sid();
4181}
4182
4183static void selinux_task_getlsmprop_obj(struct task_struct *p,
4184 struct lsm_prop *prop)
4185{
4186 prop->selinux.secid = task_sid_obj(p);
4187}
4188
4189static int selinux_task_setnice(struct task_struct *p, int nice)
4190{
4191 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4192 PROCESS__SETSCHED, NULL);
4193}
4194
4195static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4196{
4197 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4198 PROCESS__SETSCHED, NULL);
4199}
4200
4201static int selinux_task_getioprio(struct task_struct *p)
4202{
4203 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4204 PROCESS__GETSCHED, NULL);
4205}
4206
4207static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4208 unsigned int flags)
4209{
4210 u32 av = 0;
4211
4212 if (!flags)
4213 return 0;
4214 if (flags & LSM_PRLIMIT_WRITE)
4215 av |= PROCESS__SETRLIMIT;
4216 if (flags & LSM_PRLIMIT_READ)
4217 av |= PROCESS__GETRLIMIT;
4218 return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4219 SECCLASS_PROCESS, av, NULL);
4220}
4221
4222static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4223 struct rlimit *new_rlim)
4224{
4225 struct rlimit *old_rlim = p->signal->rlim + resource;
4226
4227 /* Control the ability to change the hard limit (whether
4228 lowering or raising it), so that the hard limit can
4229 later be used as a safe reset point for the soft limit
4230 upon context transitions. See selinux_bprm_committing_creds. */
4231 if (old_rlim->rlim_max != new_rlim->rlim_max)
4232 return avc_has_perm(current_sid(), task_sid_obj(p),
4233 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4234
4235 return 0;
4236}
4237
4238static int selinux_task_setscheduler(struct task_struct *p)
4239{
4240 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4241 PROCESS__SETSCHED, NULL);
4242}
4243
4244static int selinux_task_getscheduler(struct task_struct *p)
4245{
4246 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4247 PROCESS__GETSCHED, NULL);
4248}
4249
4250static int selinux_task_movememory(struct task_struct *p)
4251{
4252 return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4253 PROCESS__SETSCHED, NULL);
4254}
4255
4256static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4257 int sig, const struct cred *cred)
4258{
4259 u32 secid;
4260 u32 perm;
4261
4262 if (!sig)
4263 perm = PROCESS__SIGNULL; /* null signal; existence test */
4264 else
4265 perm = signal_to_av(sig);
4266 if (!cred)
4267 secid = current_sid();
4268 else
4269 secid = cred_sid(cred);
4270 return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4271}
4272
4273static void selinux_task_to_inode(struct task_struct *p,
4274 struct inode *inode)
4275{
4276 struct inode_security_struct *isec = selinux_inode(inode);
4277 u32 sid = task_sid_obj(p);
4278
4279 spin_lock(&isec->lock);
4280 isec->sclass = inode_mode_to_security_class(inode->i_mode);
4281 isec->sid = sid;
4282 isec->initialized = LABEL_INITIALIZED;
4283 spin_unlock(&isec->lock);
4284}
4285
4286static int selinux_userns_create(const struct cred *cred)
4287{
4288 u32 sid = current_sid();
4289
4290 return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4291 USER_NAMESPACE__CREATE, NULL);
4292}
4293
4294/* Returns error only if unable to parse addresses */
4295static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4296 struct common_audit_data *ad, u8 *proto)
4297{
4298 int offset, ihlen, ret = -EINVAL;
4299 struct iphdr _iph, *ih;
4300
4301 offset = skb_network_offset(skb);
4302 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4303 if (ih == NULL)
4304 goto out;
4305
4306 ihlen = ih->ihl * 4;
4307 if (ihlen < sizeof(_iph))
4308 goto out;
4309
4310 ad->u.net->v4info.saddr = ih->saddr;
4311 ad->u.net->v4info.daddr = ih->daddr;
4312 ret = 0;
4313
4314 if (proto)
4315 *proto = ih->protocol;
4316
4317 switch (ih->protocol) {
4318 case IPPROTO_TCP: {
4319 struct tcphdr _tcph, *th;
4320
4321 if (ntohs(ih->frag_off) & IP_OFFSET)
4322 break;
4323
4324 offset += ihlen;
4325 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4326 if (th == NULL)
4327 break;
4328
4329 ad->u.net->sport = th->source;
4330 ad->u.net->dport = th->dest;
4331 break;
4332 }
4333
4334 case IPPROTO_UDP: {
4335 struct udphdr _udph, *uh;
4336
4337 if (ntohs(ih->frag_off) & IP_OFFSET)
4338 break;
4339
4340 offset += ihlen;
4341 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4342 if (uh == NULL)
4343 break;
4344
4345 ad->u.net->sport = uh->source;
4346 ad->u.net->dport = uh->dest;
4347 break;
4348 }
4349
4350 case IPPROTO_DCCP: {
4351 struct dccp_hdr _dccph, *dh;
4352
4353 if (ntohs(ih->frag_off) & IP_OFFSET)
4354 break;
4355
4356 offset += ihlen;
4357 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4358 if (dh == NULL)
4359 break;
4360
4361 ad->u.net->sport = dh->dccph_sport;
4362 ad->u.net->dport = dh->dccph_dport;
4363 break;
4364 }
4365
4366#if IS_ENABLED(CONFIG_IP_SCTP)
4367 case IPPROTO_SCTP: {
4368 struct sctphdr _sctph, *sh;
4369
4370 if (ntohs(ih->frag_off) & IP_OFFSET)
4371 break;
4372
4373 offset += ihlen;
4374 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4375 if (sh == NULL)
4376 break;
4377
4378 ad->u.net->sport = sh->source;
4379 ad->u.net->dport = sh->dest;
4380 break;
4381 }
4382#endif
4383 default:
4384 break;
4385 }
4386out:
4387 return ret;
4388}
4389
4390#if IS_ENABLED(CONFIG_IPV6)
4391
4392/* Returns error only if unable to parse addresses */
4393static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4394 struct common_audit_data *ad, u8 *proto)
4395{
4396 u8 nexthdr;
4397 int ret = -EINVAL, offset;
4398 struct ipv6hdr _ipv6h, *ip6;
4399 __be16 frag_off;
4400
4401 offset = skb_network_offset(skb);
4402 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4403 if (ip6 == NULL)
4404 goto out;
4405
4406 ad->u.net->v6info.saddr = ip6->saddr;
4407 ad->u.net->v6info.daddr = ip6->daddr;
4408 ret = 0;
4409
4410 nexthdr = ip6->nexthdr;
4411 offset += sizeof(_ipv6h);
4412 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4413 if (offset < 0)
4414 goto out;
4415
4416 if (proto)
4417 *proto = nexthdr;
4418
4419 switch (nexthdr) {
4420 case IPPROTO_TCP: {
4421 struct tcphdr _tcph, *th;
4422
4423 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4424 if (th == NULL)
4425 break;
4426
4427 ad->u.net->sport = th->source;
4428 ad->u.net->dport = th->dest;
4429 break;
4430 }
4431
4432 case IPPROTO_UDP: {
4433 struct udphdr _udph, *uh;
4434
4435 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4436 if (uh == NULL)
4437 break;
4438
4439 ad->u.net->sport = uh->source;
4440 ad->u.net->dport = uh->dest;
4441 break;
4442 }
4443
4444 case IPPROTO_DCCP: {
4445 struct dccp_hdr _dccph, *dh;
4446
4447 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4448 if (dh == NULL)
4449 break;
4450
4451 ad->u.net->sport = dh->dccph_sport;
4452 ad->u.net->dport = dh->dccph_dport;
4453 break;
4454 }
4455
4456#if IS_ENABLED(CONFIG_IP_SCTP)
4457 case IPPROTO_SCTP: {
4458 struct sctphdr _sctph, *sh;
4459
4460 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4461 if (sh == NULL)
4462 break;
4463
4464 ad->u.net->sport = sh->source;
4465 ad->u.net->dport = sh->dest;
4466 break;
4467 }
4468#endif
4469 /* includes fragments */
4470 default:
4471 break;
4472 }
4473out:
4474 return ret;
4475}
4476
4477#endif /* IPV6 */
4478
4479static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4480 char **_addrp, int src, u8 *proto)
4481{
4482 char *addrp;
4483 int ret;
4484
4485 switch (ad->u.net->family) {
4486 case PF_INET:
4487 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4488 if (ret)
4489 goto parse_error;
4490 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4491 &ad->u.net->v4info.daddr);
4492 goto okay;
4493
4494#if IS_ENABLED(CONFIG_IPV6)
4495 case PF_INET6:
4496 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4497 if (ret)
4498 goto parse_error;
4499 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4500 &ad->u.net->v6info.daddr);
4501 goto okay;
4502#endif /* IPV6 */
4503 default:
4504 addrp = NULL;
4505 goto okay;
4506 }
4507
4508parse_error:
4509 pr_warn(
4510 "SELinux: failure in selinux_parse_skb(),"
4511 " unable to parse packet\n");
4512 return ret;
4513
4514okay:
4515 if (_addrp)
4516 *_addrp = addrp;
4517 return 0;
4518}
4519
4520/**
4521 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4522 * @skb: the packet
4523 * @family: protocol family
4524 * @sid: the packet's peer label SID
4525 *
4526 * Description:
4527 * Check the various different forms of network peer labeling and determine
4528 * the peer label/SID for the packet; most of the magic actually occurs in
4529 * the security server function security_net_peersid_cmp(). The function
4530 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4531 * or -EACCES if @sid is invalid due to inconsistencies with the different
4532 * peer labels.
4533 *
4534 */
4535static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4536{
4537 int err;
4538 u32 xfrm_sid;
4539 u32 nlbl_sid;
4540 u32 nlbl_type;
4541
4542 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4543 if (unlikely(err))
4544 return -EACCES;
4545 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4546 if (unlikely(err))
4547 return -EACCES;
4548
4549 err = security_net_peersid_resolve(nlbl_sid,
4550 nlbl_type, xfrm_sid, sid);
4551 if (unlikely(err)) {
4552 pr_warn(
4553 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4554 " unable to determine packet's peer label\n");
4555 return -EACCES;
4556 }
4557
4558 return 0;
4559}
4560
4561/**
4562 * selinux_conn_sid - Determine the child socket label for a connection
4563 * @sk_sid: the parent socket's SID
4564 * @skb_sid: the packet's SID
4565 * @conn_sid: the resulting connection SID
4566 *
4567 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4568 * combined with the MLS information from @skb_sid in order to create
4569 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy
4570 * of @sk_sid. Returns zero on success, negative values on failure.
4571 *
4572 */
4573static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4574{
4575 int err = 0;
4576
4577 if (skb_sid != SECSID_NULL)
4578 err = security_sid_mls_copy(sk_sid, skb_sid,
4579 conn_sid);
4580 else
4581 *conn_sid = sk_sid;
4582
4583 return err;
4584}
4585
4586/* socket security operations */
4587
4588static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4589 u16 secclass, u32 *socksid)
4590{
4591 if (tsec->sockcreate_sid > SECSID_NULL) {
4592 *socksid = tsec->sockcreate_sid;
4593 return 0;
4594 }
4595
4596 return security_transition_sid(tsec->sid, tsec->sid,
4597 secclass, NULL, socksid);
4598}
4599
4600static bool sock_skip_has_perm(u32 sid)
4601{
4602 if (sid == SECINITSID_KERNEL)
4603 return true;
4604
4605 /*
4606 * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4607 * inherited the kernel context from early boot used to be skipped
4608 * here, so preserve that behavior unless the capability is set.
4609 *
4610 * By setting the capability the policy signals that it is ready
4611 * for this quirk to be fixed. Note that sockets created by a kernel
4612 * thread or a usermode helper executed without a transition will
4613 * still be skipped in this check regardless of the policycap
4614 * setting.
4615 */
4616 if (!selinux_policycap_userspace_initial_context() &&
4617 sid == SECINITSID_INIT)
4618 return true;
4619 return false;
4620}
4621
4622
4623static int sock_has_perm(struct sock *sk, u32 perms)
4624{
4625 struct sk_security_struct *sksec = sk->sk_security;
4626 struct common_audit_data ad;
4627 struct lsm_network_audit net;
4628
4629 if (sock_skip_has_perm(sksec->sid))
4630 return 0;
4631
4632 ad_net_init_from_sk(&ad, &net, sk);
4633
4634 return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4635 &ad);
4636}
4637
4638static int selinux_socket_create(int family, int type,
4639 int protocol, int kern)
4640{
4641 const struct task_security_struct *tsec = selinux_cred(current_cred());
4642 u32 newsid;
4643 u16 secclass;
4644 int rc;
4645
4646 if (kern)
4647 return 0;
4648
4649 secclass = socket_type_to_security_class(family, type, protocol);
4650 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4651 if (rc)
4652 return rc;
4653
4654 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4655}
4656
4657static int selinux_socket_post_create(struct socket *sock, int family,
4658 int type, int protocol, int kern)
4659{
4660 const struct task_security_struct *tsec = selinux_cred(current_cred());
4661 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4662 struct sk_security_struct *sksec;
4663 u16 sclass = socket_type_to_security_class(family, type, protocol);
4664 u32 sid = SECINITSID_KERNEL;
4665 int err = 0;
4666
4667 if (!kern) {
4668 err = socket_sockcreate_sid(tsec, sclass, &sid);
4669 if (err)
4670 return err;
4671 }
4672
4673 isec->sclass = sclass;
4674 isec->sid = sid;
4675 isec->initialized = LABEL_INITIALIZED;
4676
4677 if (sock->sk) {
4678 sksec = selinux_sock(sock->sk);
4679 sksec->sclass = sclass;
4680 sksec->sid = sid;
4681 /* Allows detection of the first association on this socket */
4682 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4683 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4684
4685 err = selinux_netlbl_socket_post_create(sock->sk, family);
4686 }
4687
4688 return err;
4689}
4690
4691static int selinux_socket_socketpair(struct socket *socka,
4692 struct socket *sockb)
4693{
4694 struct sk_security_struct *sksec_a = selinux_sock(socka->sk);
4695 struct sk_security_struct *sksec_b = selinux_sock(sockb->sk);
4696
4697 sksec_a->peer_sid = sksec_b->sid;
4698 sksec_b->peer_sid = sksec_a->sid;
4699
4700 return 0;
4701}
4702
4703/* Range of port numbers used to automatically bind.
4704 Need to determine whether we should perform a name_bind
4705 permission check between the socket and the port number. */
4706
4707static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4708{
4709 struct sock *sk = sock->sk;
4710 struct sk_security_struct *sksec = selinux_sock(sk);
4711 u16 family;
4712 int err;
4713
4714 err = sock_has_perm(sk, SOCKET__BIND);
4715 if (err)
4716 goto out;
4717
4718 /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4719 family = sk->sk_family;
4720 if (family == PF_INET || family == PF_INET6) {
4721 char *addrp;
4722 struct common_audit_data ad;
4723 struct lsm_network_audit net = {0,};
4724 struct sockaddr_in *addr4 = NULL;
4725 struct sockaddr_in6 *addr6 = NULL;
4726 u16 family_sa;
4727 unsigned short snum;
4728 u32 sid, node_perm;
4729
4730 /*
4731 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4732 * that validates multiple binding addresses. Because of this
4733 * need to check address->sa_family as it is possible to have
4734 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4735 */
4736 if (addrlen < offsetofend(struct sockaddr, sa_family))
4737 return -EINVAL;
4738 family_sa = address->sa_family;
4739 switch (family_sa) {
4740 case AF_UNSPEC:
4741 case AF_INET:
4742 if (addrlen < sizeof(struct sockaddr_in))
4743 return -EINVAL;
4744 addr4 = (struct sockaddr_in *)address;
4745 if (family_sa == AF_UNSPEC) {
4746 if (family == PF_INET6) {
4747 /* Length check from inet6_bind_sk() */
4748 if (addrlen < SIN6_LEN_RFC2133)
4749 return -EINVAL;
4750 /* Family check from __inet6_bind() */
4751 goto err_af;
4752 }
4753 /* see __inet_bind(), we only want to allow
4754 * AF_UNSPEC if the address is INADDR_ANY
4755 */
4756 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4757 goto err_af;
4758 family_sa = AF_INET;
4759 }
4760 snum = ntohs(addr4->sin_port);
4761 addrp = (char *)&addr4->sin_addr.s_addr;
4762 break;
4763 case AF_INET6:
4764 if (addrlen < SIN6_LEN_RFC2133)
4765 return -EINVAL;
4766 addr6 = (struct sockaddr_in6 *)address;
4767 snum = ntohs(addr6->sin6_port);
4768 addrp = (char *)&addr6->sin6_addr.s6_addr;
4769 break;
4770 default:
4771 goto err_af;
4772 }
4773
4774 ad.type = LSM_AUDIT_DATA_NET;
4775 ad.u.net = &net;
4776 ad.u.net->sport = htons(snum);
4777 ad.u.net->family = family_sa;
4778
4779 if (snum) {
4780 int low, high;
4781
4782 inet_get_local_port_range(sock_net(sk), &low, &high);
4783
4784 if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4785 snum < low || snum > high) {
4786 err = sel_netport_sid(sk->sk_protocol,
4787 snum, &sid);
4788 if (err)
4789 goto out;
4790 err = avc_has_perm(sksec->sid, sid,
4791 sksec->sclass,
4792 SOCKET__NAME_BIND, &ad);
4793 if (err)
4794 goto out;
4795 }
4796 }
4797
4798 switch (sksec->sclass) {
4799 case SECCLASS_TCP_SOCKET:
4800 node_perm = TCP_SOCKET__NODE_BIND;
4801 break;
4802
4803 case SECCLASS_UDP_SOCKET:
4804 node_perm = UDP_SOCKET__NODE_BIND;
4805 break;
4806
4807 case SECCLASS_DCCP_SOCKET:
4808 node_perm = DCCP_SOCKET__NODE_BIND;
4809 break;
4810
4811 case SECCLASS_SCTP_SOCKET:
4812 node_perm = SCTP_SOCKET__NODE_BIND;
4813 break;
4814
4815 default:
4816 node_perm = RAWIP_SOCKET__NODE_BIND;
4817 break;
4818 }
4819
4820 err = sel_netnode_sid(addrp, family_sa, &sid);
4821 if (err)
4822 goto out;
4823
4824 if (family_sa == AF_INET)
4825 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4826 else
4827 ad.u.net->v6info.saddr = addr6->sin6_addr;
4828
4829 err = avc_has_perm(sksec->sid, sid,
4830 sksec->sclass, node_perm, &ad);
4831 if (err)
4832 goto out;
4833 }
4834out:
4835 return err;
4836err_af:
4837 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4838 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4839 return -EINVAL;
4840 return -EAFNOSUPPORT;
4841}
4842
4843/* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4844 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4845 */
4846static int selinux_socket_connect_helper(struct socket *sock,
4847 struct sockaddr *address, int addrlen)
4848{
4849 struct sock *sk = sock->sk;
4850 struct sk_security_struct *sksec = selinux_sock(sk);
4851 int err;
4852
4853 err = sock_has_perm(sk, SOCKET__CONNECT);
4854 if (err)
4855 return err;
4856 if (addrlen < offsetofend(struct sockaddr, sa_family))
4857 return -EINVAL;
4858
4859 /* connect(AF_UNSPEC) has special handling, as it is a documented
4860 * way to disconnect the socket
4861 */
4862 if (address->sa_family == AF_UNSPEC)
4863 return 0;
4864
4865 /*
4866 * If a TCP, DCCP or SCTP socket, check name_connect permission
4867 * for the port.
4868 */
4869 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4870 sksec->sclass == SECCLASS_DCCP_SOCKET ||
4871 sksec->sclass == SECCLASS_SCTP_SOCKET) {
4872 struct common_audit_data ad;
4873 struct lsm_network_audit net = {0,};
4874 struct sockaddr_in *addr4 = NULL;
4875 struct sockaddr_in6 *addr6 = NULL;
4876 unsigned short snum;
4877 u32 sid, perm;
4878
4879 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4880 * that validates multiple connect addresses. Because of this
4881 * need to check address->sa_family as it is possible to have
4882 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4883 */
4884 switch (address->sa_family) {
4885 case AF_INET:
4886 addr4 = (struct sockaddr_in *)address;
4887 if (addrlen < sizeof(struct sockaddr_in))
4888 return -EINVAL;
4889 snum = ntohs(addr4->sin_port);
4890 break;
4891 case AF_INET6:
4892 addr6 = (struct sockaddr_in6 *)address;
4893 if (addrlen < SIN6_LEN_RFC2133)
4894 return -EINVAL;
4895 snum = ntohs(addr6->sin6_port);
4896 break;
4897 default:
4898 /* Note that SCTP services expect -EINVAL, whereas
4899 * others expect -EAFNOSUPPORT.
4900 */
4901 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4902 return -EINVAL;
4903 else
4904 return -EAFNOSUPPORT;
4905 }
4906
4907 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4908 if (err)
4909 return err;
4910
4911 switch (sksec->sclass) {
4912 case SECCLASS_TCP_SOCKET:
4913 perm = TCP_SOCKET__NAME_CONNECT;
4914 break;
4915 case SECCLASS_DCCP_SOCKET:
4916 perm = DCCP_SOCKET__NAME_CONNECT;
4917 break;
4918 case SECCLASS_SCTP_SOCKET:
4919 perm = SCTP_SOCKET__NAME_CONNECT;
4920 break;
4921 }
4922
4923 ad.type = LSM_AUDIT_DATA_NET;
4924 ad.u.net = &net;
4925 ad.u.net->dport = htons(snum);
4926 ad.u.net->family = address->sa_family;
4927 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4928 if (err)
4929 return err;
4930 }
4931
4932 return 0;
4933}
4934
4935/* Supports connect(2), see comments in selinux_socket_connect_helper() */
4936static int selinux_socket_connect(struct socket *sock,
4937 struct sockaddr *address, int addrlen)
4938{
4939 int err;
4940 struct sock *sk = sock->sk;
4941
4942 err = selinux_socket_connect_helper(sock, address, addrlen);
4943 if (err)
4944 return err;
4945
4946 return selinux_netlbl_socket_connect(sk, address);
4947}
4948
4949static int selinux_socket_listen(struct socket *sock, int backlog)
4950{
4951 return sock_has_perm(sock->sk, SOCKET__LISTEN);
4952}
4953
4954static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4955{
4956 int err;
4957 struct inode_security_struct *isec;
4958 struct inode_security_struct *newisec;
4959 u16 sclass;
4960 u32 sid;
4961
4962 err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4963 if (err)
4964 return err;
4965
4966 isec = inode_security_novalidate(SOCK_INODE(sock));
4967 spin_lock(&isec->lock);
4968 sclass = isec->sclass;
4969 sid = isec->sid;
4970 spin_unlock(&isec->lock);
4971
4972 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4973 newisec->sclass = sclass;
4974 newisec->sid = sid;
4975 newisec->initialized = LABEL_INITIALIZED;
4976
4977 return 0;
4978}
4979
4980static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4981 int size)
4982{
4983 return sock_has_perm(sock->sk, SOCKET__WRITE);
4984}
4985
4986static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4987 int size, int flags)
4988{
4989 return sock_has_perm(sock->sk, SOCKET__READ);
4990}
4991
4992static int selinux_socket_getsockname(struct socket *sock)
4993{
4994 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4995}
4996
4997static int selinux_socket_getpeername(struct socket *sock)
4998{
4999 return sock_has_perm(sock->sk, SOCKET__GETATTR);
5000}
5001
5002static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
5003{
5004 int err;
5005
5006 err = sock_has_perm(sock->sk, SOCKET__SETOPT);
5007 if (err)
5008 return err;
5009
5010 return selinux_netlbl_socket_setsockopt(sock, level, optname);
5011}
5012
5013static int selinux_socket_getsockopt(struct socket *sock, int level,
5014 int optname)
5015{
5016 return sock_has_perm(sock->sk, SOCKET__GETOPT);
5017}
5018
5019static int selinux_socket_shutdown(struct socket *sock, int how)
5020{
5021 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
5022}
5023
5024static int selinux_socket_unix_stream_connect(struct sock *sock,
5025 struct sock *other,
5026 struct sock *newsk)
5027{
5028 struct sk_security_struct *sksec_sock = selinux_sock(sock);
5029 struct sk_security_struct *sksec_other = selinux_sock(other);
5030 struct sk_security_struct *sksec_new = selinux_sock(newsk);
5031 struct common_audit_data ad;
5032 struct lsm_network_audit net;
5033 int err;
5034
5035 ad_net_init_from_sk(&ad, &net, other);
5036
5037 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5038 sksec_other->sclass,
5039 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5040 if (err)
5041 return err;
5042
5043 /* server child socket */
5044 sksec_new->peer_sid = sksec_sock->sid;
5045 err = security_sid_mls_copy(sksec_other->sid,
5046 sksec_sock->sid, &sksec_new->sid);
5047 if (err)
5048 return err;
5049
5050 /* connecting socket */
5051 sksec_sock->peer_sid = sksec_new->sid;
5052
5053 return 0;
5054}
5055
5056static int selinux_socket_unix_may_send(struct socket *sock,
5057 struct socket *other)
5058{
5059 struct sk_security_struct *ssec = selinux_sock(sock->sk);
5060 struct sk_security_struct *osec = selinux_sock(other->sk);
5061 struct common_audit_data ad;
5062 struct lsm_network_audit net;
5063
5064 ad_net_init_from_sk(&ad, &net, other->sk);
5065
5066 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5067 &ad);
5068}
5069
5070static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5071 char *addrp, u16 family, u32 peer_sid,
5072 struct common_audit_data *ad)
5073{
5074 int err;
5075 u32 if_sid;
5076 u32 node_sid;
5077
5078 err = sel_netif_sid(ns, ifindex, &if_sid);
5079 if (err)
5080 return err;
5081 err = avc_has_perm(peer_sid, if_sid,
5082 SECCLASS_NETIF, NETIF__INGRESS, ad);
5083 if (err)
5084 return err;
5085
5086 err = sel_netnode_sid(addrp, family, &node_sid);
5087 if (err)
5088 return err;
5089 return avc_has_perm(peer_sid, node_sid,
5090 SECCLASS_NODE, NODE__RECVFROM, ad);
5091}
5092
5093static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5094 u16 family)
5095{
5096 int err = 0;
5097 struct sk_security_struct *sksec = selinux_sock(sk);
5098 u32 sk_sid = sksec->sid;
5099 struct common_audit_data ad;
5100 struct lsm_network_audit net;
5101 char *addrp;
5102
5103 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5104 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5105 if (err)
5106 return err;
5107
5108 if (selinux_secmark_enabled()) {
5109 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5110 PACKET__RECV, &ad);
5111 if (err)
5112 return err;
5113 }
5114
5115 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5116 if (err)
5117 return err;
5118 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5119
5120 return err;
5121}
5122
5123static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5124{
5125 int err, peerlbl_active, secmark_active;
5126 struct sk_security_struct *sksec = selinux_sock(sk);
5127 u16 family = sk->sk_family;
5128 u32 sk_sid = sksec->sid;
5129 struct common_audit_data ad;
5130 struct lsm_network_audit net;
5131 char *addrp;
5132
5133 if (family != PF_INET && family != PF_INET6)
5134 return 0;
5135
5136 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5137 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5138 family = PF_INET;
5139
5140 /* If any sort of compatibility mode is enabled then handoff processing
5141 * to the selinux_sock_rcv_skb_compat() function to deal with the
5142 * special handling. We do this in an attempt to keep this function
5143 * as fast and as clean as possible. */
5144 if (!selinux_policycap_netpeer())
5145 return selinux_sock_rcv_skb_compat(sk, skb, family);
5146
5147 secmark_active = selinux_secmark_enabled();
5148 peerlbl_active = selinux_peerlbl_enabled();
5149 if (!secmark_active && !peerlbl_active)
5150 return 0;
5151
5152 ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5153 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5154 if (err)
5155 return err;
5156
5157 if (peerlbl_active) {
5158 u32 peer_sid;
5159
5160 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5161 if (err)
5162 return err;
5163 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5164 addrp, family, peer_sid, &ad);
5165 if (err) {
5166 selinux_netlbl_err(skb, family, err, 0);
5167 return err;
5168 }
5169 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5170 PEER__RECV, &ad);
5171 if (err) {
5172 selinux_netlbl_err(skb, family, err, 0);
5173 return err;
5174 }
5175 }
5176
5177 if (secmark_active) {
5178 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5179 PACKET__RECV, &ad);
5180 if (err)
5181 return err;
5182 }
5183
5184 return err;
5185}
5186
5187static int selinux_socket_getpeersec_stream(struct socket *sock,
5188 sockptr_t optval, sockptr_t optlen,
5189 unsigned int len)
5190{
5191 int err = 0;
5192 char *scontext = NULL;
5193 u32 scontext_len;
5194 struct sk_security_struct *sksec = selinux_sock(sock->sk);
5195 u32 peer_sid = SECSID_NULL;
5196
5197 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5198 sksec->sclass == SECCLASS_TCP_SOCKET ||
5199 sksec->sclass == SECCLASS_SCTP_SOCKET)
5200 peer_sid = sksec->peer_sid;
5201 if (peer_sid == SECSID_NULL)
5202 return -ENOPROTOOPT;
5203
5204 err = security_sid_to_context(peer_sid, &scontext,
5205 &scontext_len);
5206 if (err)
5207 return err;
5208 if (scontext_len > len) {
5209 err = -ERANGE;
5210 goto out_len;
5211 }
5212
5213 if (copy_to_sockptr(optval, scontext, scontext_len))
5214 err = -EFAULT;
5215out_len:
5216 if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5217 err = -EFAULT;
5218 kfree(scontext);
5219 return err;
5220}
5221
5222static int selinux_socket_getpeersec_dgram(struct socket *sock,
5223 struct sk_buff *skb, u32 *secid)
5224{
5225 u32 peer_secid = SECSID_NULL;
5226 u16 family;
5227
5228 if (skb && skb->protocol == htons(ETH_P_IP))
5229 family = PF_INET;
5230 else if (skb && skb->protocol == htons(ETH_P_IPV6))
5231 family = PF_INET6;
5232 else if (sock)
5233 family = sock->sk->sk_family;
5234 else {
5235 *secid = SECSID_NULL;
5236 return -EINVAL;
5237 }
5238
5239 if (sock && family == PF_UNIX) {
5240 struct inode_security_struct *isec;
5241 isec = inode_security_novalidate(SOCK_INODE(sock));
5242 peer_secid = isec->sid;
5243 } else if (skb)
5244 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5245
5246 *secid = peer_secid;
5247 if (peer_secid == SECSID_NULL)
5248 return -ENOPROTOOPT;
5249 return 0;
5250}
5251
5252static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5253{
5254 struct sk_security_struct *sksec = selinux_sock(sk);
5255
5256 sksec->peer_sid = SECINITSID_UNLABELED;
5257 sksec->sid = SECINITSID_UNLABELED;
5258 sksec->sclass = SECCLASS_SOCKET;
5259 selinux_netlbl_sk_security_reset(sksec);
5260
5261 return 0;
5262}
5263
5264static void selinux_sk_free_security(struct sock *sk)
5265{
5266 struct sk_security_struct *sksec = selinux_sock(sk);
5267
5268 selinux_netlbl_sk_security_free(sksec);
5269}
5270
5271static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5272{
5273 struct sk_security_struct *sksec = selinux_sock(sk);
5274 struct sk_security_struct *newsksec = selinux_sock(newsk);
5275
5276 newsksec->sid = sksec->sid;
5277 newsksec->peer_sid = sksec->peer_sid;
5278 newsksec->sclass = sksec->sclass;
5279
5280 selinux_netlbl_sk_security_reset(newsksec);
5281}
5282
5283static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5284{
5285 if (!sk)
5286 *secid = SECINITSID_ANY_SOCKET;
5287 else {
5288 const struct sk_security_struct *sksec = selinux_sock(sk);
5289
5290 *secid = sksec->sid;
5291 }
5292}
5293
5294static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5295{
5296 struct inode_security_struct *isec =
5297 inode_security_novalidate(SOCK_INODE(parent));
5298 struct sk_security_struct *sksec = selinux_sock(sk);
5299
5300 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5301 sk->sk_family == PF_UNIX)
5302 isec->sid = sksec->sid;
5303 sksec->sclass = isec->sclass;
5304}
5305
5306/*
5307 * Determines peer_secid for the asoc and updates socket's peer label
5308 * if it's the first association on the socket.
5309 */
5310static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5311 struct sk_buff *skb)
5312{
5313 struct sock *sk = asoc->base.sk;
5314 u16 family = sk->sk_family;
5315 struct sk_security_struct *sksec = selinux_sock(sk);
5316 struct common_audit_data ad;
5317 struct lsm_network_audit net;
5318 int err;
5319
5320 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5321 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5322 family = PF_INET;
5323
5324 if (selinux_peerlbl_enabled()) {
5325 asoc->peer_secid = SECSID_NULL;
5326
5327 /* This will return peer_sid = SECSID_NULL if there are
5328 * no peer labels, see security_net_peersid_resolve().
5329 */
5330 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5331 if (err)
5332 return err;
5333
5334 if (asoc->peer_secid == SECSID_NULL)
5335 asoc->peer_secid = SECINITSID_UNLABELED;
5336 } else {
5337 asoc->peer_secid = SECINITSID_UNLABELED;
5338 }
5339
5340 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5341 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5342
5343 /* Here as first association on socket. As the peer SID
5344 * was allowed by peer recv (and the netif/node checks),
5345 * then it is approved by policy and used as the primary
5346 * peer SID for getpeercon(3).
5347 */
5348 sksec->peer_sid = asoc->peer_secid;
5349 } else if (sksec->peer_sid != asoc->peer_secid) {
5350 /* Other association peer SIDs are checked to enforce
5351 * consistency among the peer SIDs.
5352 */
5353 ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5354 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5355 sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5356 &ad);
5357 if (err)
5358 return err;
5359 }
5360 return 0;
5361}
5362
5363/* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5364 * happens on an incoming connect(2), sctp_connectx(3) or
5365 * sctp_sendmsg(3) (with no association already present).
5366 */
5367static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5368 struct sk_buff *skb)
5369{
5370 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5371 u32 conn_sid;
5372 int err;
5373
5374 if (!selinux_policycap_extsockclass())
5375 return 0;
5376
5377 err = selinux_sctp_process_new_assoc(asoc, skb);
5378 if (err)
5379 return err;
5380
5381 /* Compute the MLS component for the connection and store
5382 * the information in asoc. This will be used by SCTP TCP type
5383 * sockets and peeled off connections as they cause a new
5384 * socket to be generated. selinux_sctp_sk_clone() will then
5385 * plug this into the new socket.
5386 */
5387 err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5388 if (err)
5389 return err;
5390
5391 asoc->secid = conn_sid;
5392
5393 /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5394 return selinux_netlbl_sctp_assoc_request(asoc, skb);
5395}
5396
5397/* Called when SCTP receives a COOKIE ACK chunk as the final
5398 * response to an association request (initited by us).
5399 */
5400static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5401 struct sk_buff *skb)
5402{
5403 struct sk_security_struct *sksec = selinux_sock(asoc->base.sk);
5404
5405 if (!selinux_policycap_extsockclass())
5406 return 0;
5407
5408 /* Inherit secid from the parent socket - this will be picked up
5409 * by selinux_sctp_sk_clone() if the association gets peeled off
5410 * into a new socket.
5411 */
5412 asoc->secid = sksec->sid;
5413
5414 return selinux_sctp_process_new_assoc(asoc, skb);
5415}
5416
5417/* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5418 * based on their @optname.
5419 */
5420static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5421 struct sockaddr *address,
5422 int addrlen)
5423{
5424 int len, err = 0, walk_size = 0;
5425 void *addr_buf;
5426 struct sockaddr *addr;
5427 struct socket *sock;
5428
5429 if (!selinux_policycap_extsockclass())
5430 return 0;
5431
5432 /* Process one or more addresses that may be IPv4 or IPv6 */
5433 sock = sk->sk_socket;
5434 addr_buf = address;
5435
5436 while (walk_size < addrlen) {
5437 if (walk_size + sizeof(sa_family_t) > addrlen)
5438 return -EINVAL;
5439
5440 addr = addr_buf;
5441 switch (addr->sa_family) {
5442 case AF_UNSPEC:
5443 case AF_INET:
5444 len = sizeof(struct sockaddr_in);
5445 break;
5446 case AF_INET6:
5447 len = sizeof(struct sockaddr_in6);
5448 break;
5449 default:
5450 return -EINVAL;
5451 }
5452
5453 if (walk_size + len > addrlen)
5454 return -EINVAL;
5455
5456 err = -EINVAL;
5457 switch (optname) {
5458 /* Bind checks */
5459 case SCTP_PRIMARY_ADDR:
5460 case SCTP_SET_PEER_PRIMARY_ADDR:
5461 case SCTP_SOCKOPT_BINDX_ADD:
5462 err = selinux_socket_bind(sock, addr, len);
5463 break;
5464 /* Connect checks */
5465 case SCTP_SOCKOPT_CONNECTX:
5466 case SCTP_PARAM_SET_PRIMARY:
5467 case SCTP_PARAM_ADD_IP:
5468 case SCTP_SENDMSG_CONNECT:
5469 err = selinux_socket_connect_helper(sock, addr, len);
5470 if (err)
5471 return err;
5472
5473 /* As selinux_sctp_bind_connect() is called by the
5474 * SCTP protocol layer, the socket is already locked,
5475 * therefore selinux_netlbl_socket_connect_locked()
5476 * is called here. The situations handled are:
5477 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5478 * whenever a new IP address is added or when a new
5479 * primary address is selected.
5480 * Note that an SCTP connect(2) call happens before
5481 * the SCTP protocol layer and is handled via
5482 * selinux_socket_connect().
5483 */
5484 err = selinux_netlbl_socket_connect_locked(sk, addr);
5485 break;
5486 }
5487
5488 if (err)
5489 return err;
5490
5491 addr_buf += len;
5492 walk_size += len;
5493 }
5494
5495 return 0;
5496}
5497
5498/* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5499static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5500 struct sock *newsk)
5501{
5502 struct sk_security_struct *sksec = selinux_sock(sk);
5503 struct sk_security_struct *newsksec = selinux_sock(newsk);
5504
5505 /* If policy does not support SECCLASS_SCTP_SOCKET then call
5506 * the non-sctp clone version.
5507 */
5508 if (!selinux_policycap_extsockclass())
5509 return selinux_sk_clone_security(sk, newsk);
5510
5511 newsksec->sid = asoc->secid;
5512 newsksec->peer_sid = asoc->peer_secid;
5513 newsksec->sclass = sksec->sclass;
5514 selinux_netlbl_sctp_sk_clone(sk, newsk);
5515}
5516
5517static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5518{
5519 struct sk_security_struct *ssksec = selinux_sock(ssk);
5520 struct sk_security_struct *sksec = selinux_sock(sk);
5521
5522 ssksec->sclass = sksec->sclass;
5523 ssksec->sid = sksec->sid;
5524
5525 /* replace the existing subflow label deleting the existing one
5526 * and re-recreating a new label using the updated context
5527 */
5528 selinux_netlbl_sk_security_free(ssksec);
5529 return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5530}
5531
5532static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5533 struct request_sock *req)
5534{
5535 struct sk_security_struct *sksec = selinux_sock(sk);
5536 int err;
5537 u16 family = req->rsk_ops->family;
5538 u32 connsid;
5539 u32 peersid;
5540
5541 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5542 if (err)
5543 return err;
5544 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5545 if (err)
5546 return err;
5547 req->secid = connsid;
5548 req->peer_secid = peersid;
5549
5550 return selinux_netlbl_inet_conn_request(req, family);
5551}
5552
5553static void selinux_inet_csk_clone(struct sock *newsk,
5554 const struct request_sock *req)
5555{
5556 struct sk_security_struct *newsksec = selinux_sock(newsk);
5557
5558 newsksec->sid = req->secid;
5559 newsksec->peer_sid = req->peer_secid;
5560 /* NOTE: Ideally, we should also get the isec->sid for the
5561 new socket in sync, but we don't have the isec available yet.
5562 So we will wait until sock_graft to do it, by which
5563 time it will have been created and available. */
5564
5565 /* We don't need to take any sort of lock here as we are the only
5566 * thread with access to newsksec */
5567 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5568}
5569
5570static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5571{
5572 u16 family = sk->sk_family;
5573 struct sk_security_struct *sksec = selinux_sock(sk);
5574
5575 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5576 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5577 family = PF_INET;
5578
5579 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5580}
5581
5582static int selinux_secmark_relabel_packet(u32 sid)
5583{
5584 return avc_has_perm(current_sid(), sid, SECCLASS_PACKET, PACKET__RELABELTO,
5585 NULL);
5586}
5587
5588static void selinux_secmark_refcount_inc(void)
5589{
5590 atomic_inc(&selinux_secmark_refcount);
5591}
5592
5593static void selinux_secmark_refcount_dec(void)
5594{
5595 atomic_dec(&selinux_secmark_refcount);
5596}
5597
5598static void selinux_req_classify_flow(const struct request_sock *req,
5599 struct flowi_common *flic)
5600{
5601 flic->flowic_secid = req->secid;
5602}
5603
5604static int selinux_tun_dev_alloc_security(void *security)
5605{
5606 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5607
5608 tunsec->sid = current_sid();
5609 return 0;
5610}
5611
5612static int selinux_tun_dev_create(void)
5613{
5614 u32 sid = current_sid();
5615
5616 /* we aren't taking into account the "sockcreate" SID since the socket
5617 * that is being created here is not a socket in the traditional sense,
5618 * instead it is a private sock, accessible only to the kernel, and
5619 * representing a wide range of network traffic spanning multiple
5620 * connections unlike traditional sockets - check the TUN driver to
5621 * get a better understanding of why this socket is special */
5622
5623 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5624 NULL);
5625}
5626
5627static int selinux_tun_dev_attach_queue(void *security)
5628{
5629 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5630
5631 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5632 TUN_SOCKET__ATTACH_QUEUE, NULL);
5633}
5634
5635static int selinux_tun_dev_attach(struct sock *sk, void *security)
5636{
5637 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5638 struct sk_security_struct *sksec = selinux_sock(sk);
5639
5640 /* we don't currently perform any NetLabel based labeling here and it
5641 * isn't clear that we would want to do so anyway; while we could apply
5642 * labeling without the support of the TUN user the resulting labeled
5643 * traffic from the other end of the connection would almost certainly
5644 * cause confusion to the TUN user that had no idea network labeling
5645 * protocols were being used */
5646
5647 sksec->sid = tunsec->sid;
5648 sksec->sclass = SECCLASS_TUN_SOCKET;
5649
5650 return 0;
5651}
5652
5653static int selinux_tun_dev_open(void *security)
5654{
5655 struct tun_security_struct *tunsec = selinux_tun_dev(security);
5656 u32 sid = current_sid();
5657 int err;
5658
5659 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5660 TUN_SOCKET__RELABELFROM, NULL);
5661 if (err)
5662 return err;
5663 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5664 TUN_SOCKET__RELABELTO, NULL);
5665 if (err)
5666 return err;
5667 tunsec->sid = sid;
5668
5669 return 0;
5670}
5671
5672#ifdef CONFIG_NETFILTER
5673
5674static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5675 const struct nf_hook_state *state)
5676{
5677 int ifindex;
5678 u16 family;
5679 char *addrp;
5680 u32 peer_sid;
5681 struct common_audit_data ad;
5682 struct lsm_network_audit net;
5683 int secmark_active, peerlbl_active;
5684
5685 if (!selinux_policycap_netpeer())
5686 return NF_ACCEPT;
5687
5688 secmark_active = selinux_secmark_enabled();
5689 peerlbl_active = selinux_peerlbl_enabled();
5690 if (!secmark_active && !peerlbl_active)
5691 return NF_ACCEPT;
5692
5693 family = state->pf;
5694 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5695 return NF_DROP;
5696
5697 ifindex = state->in->ifindex;
5698 ad_net_init_from_iif(&ad, &net, ifindex, family);
5699 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5700 return NF_DROP;
5701
5702 if (peerlbl_active) {
5703 int err;
5704
5705 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5706 addrp, family, peer_sid, &ad);
5707 if (err) {
5708 selinux_netlbl_err(skb, family, err, 1);
5709 return NF_DROP;
5710 }
5711 }
5712
5713 if (secmark_active)
5714 if (avc_has_perm(peer_sid, skb->secmark,
5715 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5716 return NF_DROP;
5717
5718 if (netlbl_enabled())
5719 /* we do this in the FORWARD path and not the POST_ROUTING
5720 * path because we want to make sure we apply the necessary
5721 * labeling before IPsec is applied so we can leverage AH
5722 * protection */
5723 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5724 return NF_DROP;
5725
5726 return NF_ACCEPT;
5727}
5728
5729static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5730 const struct nf_hook_state *state)
5731{
5732 struct sock *sk;
5733 u32 sid;
5734
5735 if (!netlbl_enabled())
5736 return NF_ACCEPT;
5737
5738 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5739 * because we want to make sure we apply the necessary labeling
5740 * before IPsec is applied so we can leverage AH protection */
5741 sk = sk_to_full_sk(skb->sk);
5742 if (sk) {
5743 struct sk_security_struct *sksec;
5744
5745 if (sk_listener(sk))
5746 /* if the socket is the listening state then this
5747 * packet is a SYN-ACK packet which means it needs to
5748 * be labeled based on the connection/request_sock and
5749 * not the parent socket. unfortunately, we can't
5750 * lookup the request_sock yet as it isn't queued on
5751 * the parent socket until after the SYN-ACK is sent.
5752 * the "solution" is to simply pass the packet as-is
5753 * as any IP option based labeling should be copied
5754 * from the initial connection request (in the IP
5755 * layer). it is far from ideal, but until we get a
5756 * security label in the packet itself this is the
5757 * best we can do. */
5758 return NF_ACCEPT;
5759
5760 /* standard practice, label using the parent socket */
5761 sksec = selinux_sock(sk);
5762 sid = sksec->sid;
5763 } else
5764 sid = SECINITSID_KERNEL;
5765 if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5766 return NF_DROP;
5767
5768 return NF_ACCEPT;
5769}
5770
5771
5772static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5773 const struct nf_hook_state *state)
5774{
5775 struct sock *sk;
5776 struct sk_security_struct *sksec;
5777 struct common_audit_data ad;
5778 struct lsm_network_audit net;
5779 u8 proto = 0;
5780
5781 sk = skb_to_full_sk(skb);
5782 if (sk == NULL)
5783 return NF_ACCEPT;
5784 sksec = selinux_sock(sk);
5785
5786 ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5787 if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5788 return NF_DROP;
5789
5790 if (selinux_secmark_enabled())
5791 if (avc_has_perm(sksec->sid, skb->secmark,
5792 SECCLASS_PACKET, PACKET__SEND, &ad))
5793 return NF_DROP_ERR(-ECONNREFUSED);
5794
5795 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5796 return NF_DROP_ERR(-ECONNREFUSED);
5797
5798 return NF_ACCEPT;
5799}
5800
5801static unsigned int selinux_ip_postroute(void *priv,
5802 struct sk_buff *skb,
5803 const struct nf_hook_state *state)
5804{
5805 u16 family;
5806 u32 secmark_perm;
5807 u32 peer_sid;
5808 int ifindex;
5809 struct sock *sk;
5810 struct common_audit_data ad;
5811 struct lsm_network_audit net;
5812 char *addrp;
5813 int secmark_active, peerlbl_active;
5814
5815 /* If any sort of compatibility mode is enabled then handoff processing
5816 * to the selinux_ip_postroute_compat() function to deal with the
5817 * special handling. We do this in an attempt to keep this function
5818 * as fast and as clean as possible. */
5819 if (!selinux_policycap_netpeer())
5820 return selinux_ip_postroute_compat(skb, state);
5821
5822 secmark_active = selinux_secmark_enabled();
5823 peerlbl_active = selinux_peerlbl_enabled();
5824 if (!secmark_active && !peerlbl_active)
5825 return NF_ACCEPT;
5826
5827 sk = skb_to_full_sk(skb);
5828
5829#ifdef CONFIG_XFRM
5830 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5831 * packet transformation so allow the packet to pass without any checks
5832 * since we'll have another chance to perform access control checks
5833 * when the packet is on it's final way out.
5834 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5835 * is NULL, in this case go ahead and apply access control.
5836 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5837 * TCP listening state we cannot wait until the XFRM processing
5838 * is done as we will miss out on the SA label if we do;
5839 * unfortunately, this means more work, but it is only once per
5840 * connection. */
5841 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5842 !(sk && sk_listener(sk)))
5843 return NF_ACCEPT;
5844#endif
5845
5846 family = state->pf;
5847 if (sk == NULL) {
5848 /* Without an associated socket the packet is either coming
5849 * from the kernel or it is being forwarded; check the packet
5850 * to determine which and if the packet is being forwarded
5851 * query the packet directly to determine the security label. */
5852 if (skb->skb_iif) {
5853 secmark_perm = PACKET__FORWARD_OUT;
5854 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5855 return NF_DROP;
5856 } else {
5857 secmark_perm = PACKET__SEND;
5858 peer_sid = SECINITSID_KERNEL;
5859 }
5860 } else if (sk_listener(sk)) {
5861 /* Locally generated packet but the associated socket is in the
5862 * listening state which means this is a SYN-ACK packet. In
5863 * this particular case the correct security label is assigned
5864 * to the connection/request_sock but unfortunately we can't
5865 * query the request_sock as it isn't queued on the parent
5866 * socket until after the SYN-ACK packet is sent; the only
5867 * viable choice is to regenerate the label like we do in
5868 * selinux_inet_conn_request(). See also selinux_ip_output()
5869 * for similar problems. */
5870 u32 skb_sid;
5871 struct sk_security_struct *sksec;
5872
5873 sksec = selinux_sock(sk);
5874 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5875 return NF_DROP;
5876 /* At this point, if the returned skb peerlbl is SECSID_NULL
5877 * and the packet has been through at least one XFRM
5878 * transformation then we must be dealing with the "final"
5879 * form of labeled IPsec packet; since we've already applied
5880 * all of our access controls on this packet we can safely
5881 * pass the packet. */
5882 if (skb_sid == SECSID_NULL) {
5883 switch (family) {
5884 case PF_INET:
5885 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5886 return NF_ACCEPT;
5887 break;
5888 case PF_INET6:
5889 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5890 return NF_ACCEPT;
5891 break;
5892 default:
5893 return NF_DROP_ERR(-ECONNREFUSED);
5894 }
5895 }
5896 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5897 return NF_DROP;
5898 secmark_perm = PACKET__SEND;
5899 } else {
5900 /* Locally generated packet, fetch the security label from the
5901 * associated socket. */
5902 struct sk_security_struct *sksec = selinux_sock(sk);
5903 peer_sid = sksec->sid;
5904 secmark_perm = PACKET__SEND;
5905 }
5906
5907 ifindex = state->out->ifindex;
5908 ad_net_init_from_iif(&ad, &net, ifindex, family);
5909 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5910 return NF_DROP;
5911
5912 if (secmark_active)
5913 if (avc_has_perm(peer_sid, skb->secmark,
5914 SECCLASS_PACKET, secmark_perm, &ad))
5915 return NF_DROP_ERR(-ECONNREFUSED);
5916
5917 if (peerlbl_active) {
5918 u32 if_sid;
5919 u32 node_sid;
5920
5921 if (sel_netif_sid(state->net, ifindex, &if_sid))
5922 return NF_DROP;
5923 if (avc_has_perm(peer_sid, if_sid,
5924 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5925 return NF_DROP_ERR(-ECONNREFUSED);
5926
5927 if (sel_netnode_sid(addrp, family, &node_sid))
5928 return NF_DROP;
5929 if (avc_has_perm(peer_sid, node_sid,
5930 SECCLASS_NODE, NODE__SENDTO, &ad))
5931 return NF_DROP_ERR(-ECONNREFUSED);
5932 }
5933
5934 return NF_ACCEPT;
5935}
5936#endif /* CONFIG_NETFILTER */
5937
5938static int nlmsg_sock_has_extended_perms(struct sock *sk, u32 perms, u16 nlmsg_type)
5939{
5940 struct sk_security_struct *sksec = sk->sk_security;
5941 struct common_audit_data ad;
5942 struct lsm_network_audit net;
5943 u8 driver;
5944 u8 xperm;
5945
5946 if (sock_skip_has_perm(sksec->sid))
5947 return 0;
5948
5949 ad_net_init_from_sk(&ad, &net, sk);
5950
5951 driver = nlmsg_type >> 8;
5952 xperm = nlmsg_type & 0xff;
5953
5954 return avc_has_extended_perms(current_sid(), sksec->sid, sksec->sclass,
5955 perms, driver, AVC_EXT_NLMSG, xperm, &ad);
5956}
5957
5958static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5959{
5960 int rc = 0;
5961 unsigned int msg_len;
5962 unsigned int data_len = skb->len;
5963 unsigned char *data = skb->data;
5964 struct nlmsghdr *nlh;
5965 struct sk_security_struct *sksec = selinux_sock(sk);
5966 u16 sclass = sksec->sclass;
5967 u32 perm;
5968
5969 while (data_len >= nlmsg_total_size(0)) {
5970 nlh = (struct nlmsghdr *)data;
5971
5972 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5973 * users which means we can't reject skb's with bogus
5974 * length fields; our solution is to follow what
5975 * netlink_rcv_skb() does and simply skip processing at
5976 * messages with length fields that are clearly junk
5977 */
5978 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5979 return 0;
5980
5981 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5982 if (rc == 0) {
5983 if (selinux_policycap_netlink_xperm()) {
5984 rc = nlmsg_sock_has_extended_perms(
5985 sk, perm, nlh->nlmsg_type);
5986 } else {
5987 rc = sock_has_perm(sk, perm);
5988 }
5989 if (rc)
5990 return rc;
5991 } else if (rc == -EINVAL) {
5992 /* -EINVAL is a missing msg/perm mapping */
5993 pr_warn_ratelimited("SELinux: unrecognized netlink"
5994 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5995 " pid=%d comm=%s\n",
5996 sk->sk_protocol, nlh->nlmsg_type,
5997 secclass_map[sclass - 1].name,
5998 task_pid_nr(current), current->comm);
5999 if (enforcing_enabled() &&
6000 !security_get_allow_unknown())
6001 return rc;
6002 rc = 0;
6003 } else if (rc == -ENOENT) {
6004 /* -ENOENT is a missing socket/class mapping, ignore */
6005 rc = 0;
6006 } else {
6007 return rc;
6008 }
6009
6010 /* move to the next message after applying netlink padding */
6011 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
6012 if (msg_len >= data_len)
6013 return 0;
6014 data_len -= msg_len;
6015 data += msg_len;
6016 }
6017
6018 return rc;
6019}
6020
6021static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
6022{
6023 isec->sclass = sclass;
6024 isec->sid = current_sid();
6025}
6026
6027static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6028 u32 perms)
6029{
6030 struct ipc_security_struct *isec;
6031 struct common_audit_data ad;
6032 u32 sid = current_sid();
6033
6034 isec = selinux_ipc(ipc_perms);
6035
6036 ad.type = LSM_AUDIT_DATA_IPC;
6037 ad.u.ipc_id = ipc_perms->key;
6038
6039 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6040}
6041
6042static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6043{
6044 struct msg_security_struct *msec;
6045
6046 msec = selinux_msg_msg(msg);
6047 msec->sid = SECINITSID_UNLABELED;
6048
6049 return 0;
6050}
6051
6052/* message queue security operations */
6053static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6054{
6055 struct ipc_security_struct *isec;
6056 struct common_audit_data ad;
6057 u32 sid = current_sid();
6058
6059 isec = selinux_ipc(msq);
6060 ipc_init_security(isec, SECCLASS_MSGQ);
6061
6062 ad.type = LSM_AUDIT_DATA_IPC;
6063 ad.u.ipc_id = msq->key;
6064
6065 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6066 MSGQ__CREATE, &ad);
6067}
6068
6069static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6070{
6071 struct ipc_security_struct *isec;
6072 struct common_audit_data ad;
6073 u32 sid = current_sid();
6074
6075 isec = selinux_ipc(msq);
6076
6077 ad.type = LSM_AUDIT_DATA_IPC;
6078 ad.u.ipc_id = msq->key;
6079
6080 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6081 MSGQ__ASSOCIATE, &ad);
6082}
6083
6084static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6085{
6086 u32 perms;
6087
6088 switch (cmd) {
6089 case IPC_INFO:
6090 case MSG_INFO:
6091 /* No specific object, just general system-wide information. */
6092 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6093 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6094 case IPC_STAT:
6095 case MSG_STAT:
6096 case MSG_STAT_ANY:
6097 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6098 break;
6099 case IPC_SET:
6100 perms = MSGQ__SETATTR;
6101 break;
6102 case IPC_RMID:
6103 perms = MSGQ__DESTROY;
6104 break;
6105 default:
6106 return 0;
6107 }
6108
6109 return ipc_has_perm(msq, perms);
6110}
6111
6112static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6113{
6114 struct ipc_security_struct *isec;
6115 struct msg_security_struct *msec;
6116 struct common_audit_data ad;
6117 u32 sid = current_sid();
6118 int rc;
6119
6120 isec = selinux_ipc(msq);
6121 msec = selinux_msg_msg(msg);
6122
6123 /*
6124 * First time through, need to assign label to the message
6125 */
6126 if (msec->sid == SECINITSID_UNLABELED) {
6127 /*
6128 * Compute new sid based on current process and
6129 * message queue this message will be stored in
6130 */
6131 rc = security_transition_sid(sid, isec->sid,
6132 SECCLASS_MSG, NULL, &msec->sid);
6133 if (rc)
6134 return rc;
6135 }
6136
6137 ad.type = LSM_AUDIT_DATA_IPC;
6138 ad.u.ipc_id = msq->key;
6139
6140 /* Can this process write to the queue? */
6141 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6142 MSGQ__WRITE, &ad);
6143 if (!rc)
6144 /* Can this process send the message */
6145 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6146 MSG__SEND, &ad);
6147 if (!rc)
6148 /* Can the message be put in the queue? */
6149 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6150 MSGQ__ENQUEUE, &ad);
6151
6152 return rc;
6153}
6154
6155static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6156 struct task_struct *target,
6157 long type, int mode)
6158{
6159 struct ipc_security_struct *isec;
6160 struct msg_security_struct *msec;
6161 struct common_audit_data ad;
6162 u32 sid = task_sid_obj(target);
6163 int rc;
6164
6165 isec = selinux_ipc(msq);
6166 msec = selinux_msg_msg(msg);
6167
6168 ad.type = LSM_AUDIT_DATA_IPC;
6169 ad.u.ipc_id = msq->key;
6170
6171 rc = avc_has_perm(sid, isec->sid,
6172 SECCLASS_MSGQ, MSGQ__READ, &ad);
6173 if (!rc)
6174 rc = avc_has_perm(sid, msec->sid,
6175 SECCLASS_MSG, MSG__RECEIVE, &ad);
6176 return rc;
6177}
6178
6179/* Shared Memory security operations */
6180static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6181{
6182 struct ipc_security_struct *isec;
6183 struct common_audit_data ad;
6184 u32 sid = current_sid();
6185
6186 isec = selinux_ipc(shp);
6187 ipc_init_security(isec, SECCLASS_SHM);
6188
6189 ad.type = LSM_AUDIT_DATA_IPC;
6190 ad.u.ipc_id = shp->key;
6191
6192 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6193 SHM__CREATE, &ad);
6194}
6195
6196static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6197{
6198 struct ipc_security_struct *isec;
6199 struct common_audit_data ad;
6200 u32 sid = current_sid();
6201
6202 isec = selinux_ipc(shp);
6203
6204 ad.type = LSM_AUDIT_DATA_IPC;
6205 ad.u.ipc_id = shp->key;
6206
6207 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6208 SHM__ASSOCIATE, &ad);
6209}
6210
6211/* Note, at this point, shp is locked down */
6212static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6213{
6214 u32 perms;
6215
6216 switch (cmd) {
6217 case IPC_INFO:
6218 case SHM_INFO:
6219 /* No specific object, just general system-wide information. */
6220 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6221 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6222 case IPC_STAT:
6223 case SHM_STAT:
6224 case SHM_STAT_ANY:
6225 perms = SHM__GETATTR | SHM__ASSOCIATE;
6226 break;
6227 case IPC_SET:
6228 perms = SHM__SETATTR;
6229 break;
6230 case SHM_LOCK:
6231 case SHM_UNLOCK:
6232 perms = SHM__LOCK;
6233 break;
6234 case IPC_RMID:
6235 perms = SHM__DESTROY;
6236 break;
6237 default:
6238 return 0;
6239 }
6240
6241 return ipc_has_perm(shp, perms);
6242}
6243
6244static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6245 char __user *shmaddr, int shmflg)
6246{
6247 u32 perms;
6248
6249 if (shmflg & SHM_RDONLY)
6250 perms = SHM__READ;
6251 else
6252 perms = SHM__READ | SHM__WRITE;
6253
6254 return ipc_has_perm(shp, perms);
6255}
6256
6257/* Semaphore security operations */
6258static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6259{
6260 struct ipc_security_struct *isec;
6261 struct common_audit_data ad;
6262 u32 sid = current_sid();
6263
6264 isec = selinux_ipc(sma);
6265 ipc_init_security(isec, SECCLASS_SEM);
6266
6267 ad.type = LSM_AUDIT_DATA_IPC;
6268 ad.u.ipc_id = sma->key;
6269
6270 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6271 SEM__CREATE, &ad);
6272}
6273
6274static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6275{
6276 struct ipc_security_struct *isec;
6277 struct common_audit_data ad;
6278 u32 sid = current_sid();
6279
6280 isec = selinux_ipc(sma);
6281
6282 ad.type = LSM_AUDIT_DATA_IPC;
6283 ad.u.ipc_id = sma->key;
6284
6285 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6286 SEM__ASSOCIATE, &ad);
6287}
6288
6289/* Note, at this point, sma is locked down */
6290static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6291{
6292 int err;
6293 u32 perms;
6294
6295 switch (cmd) {
6296 case IPC_INFO:
6297 case SEM_INFO:
6298 /* No specific object, just general system-wide information. */
6299 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6300 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6301 case GETPID:
6302 case GETNCNT:
6303 case GETZCNT:
6304 perms = SEM__GETATTR;
6305 break;
6306 case GETVAL:
6307 case GETALL:
6308 perms = SEM__READ;
6309 break;
6310 case SETVAL:
6311 case SETALL:
6312 perms = SEM__WRITE;
6313 break;
6314 case IPC_RMID:
6315 perms = SEM__DESTROY;
6316 break;
6317 case IPC_SET:
6318 perms = SEM__SETATTR;
6319 break;
6320 case IPC_STAT:
6321 case SEM_STAT:
6322 case SEM_STAT_ANY:
6323 perms = SEM__GETATTR | SEM__ASSOCIATE;
6324 break;
6325 default:
6326 return 0;
6327 }
6328
6329 err = ipc_has_perm(sma, perms);
6330 return err;
6331}
6332
6333static int selinux_sem_semop(struct kern_ipc_perm *sma,
6334 struct sembuf *sops, unsigned nsops, int alter)
6335{
6336 u32 perms;
6337
6338 if (alter)
6339 perms = SEM__READ | SEM__WRITE;
6340 else
6341 perms = SEM__READ;
6342
6343 return ipc_has_perm(sma, perms);
6344}
6345
6346static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6347{
6348 u32 av = 0;
6349
6350 av = 0;
6351 if (flag & S_IRUGO)
6352 av |= IPC__UNIX_READ;
6353 if (flag & S_IWUGO)
6354 av |= IPC__UNIX_WRITE;
6355
6356 if (av == 0)
6357 return 0;
6358
6359 return ipc_has_perm(ipcp, av);
6360}
6361
6362static void selinux_ipc_getlsmprop(struct kern_ipc_perm *ipcp,
6363 struct lsm_prop *prop)
6364{
6365 struct ipc_security_struct *isec = selinux_ipc(ipcp);
6366 prop->selinux.secid = isec->sid;
6367}
6368
6369static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6370{
6371 if (inode)
6372 inode_doinit_with_dentry(inode, dentry);
6373}
6374
6375static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6376 char **value)
6377{
6378 const struct task_security_struct *tsec;
6379 int error;
6380 u32 sid;
6381 u32 len;
6382
6383 rcu_read_lock();
6384 tsec = selinux_cred(__task_cred(p));
6385 if (p != current) {
6386 error = avc_has_perm(current_sid(), tsec->sid,
6387 SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6388 if (error)
6389 goto err_unlock;
6390 }
6391 switch (attr) {
6392 case LSM_ATTR_CURRENT:
6393 sid = tsec->sid;
6394 break;
6395 case LSM_ATTR_PREV:
6396 sid = tsec->osid;
6397 break;
6398 case LSM_ATTR_EXEC:
6399 sid = tsec->exec_sid;
6400 break;
6401 case LSM_ATTR_FSCREATE:
6402 sid = tsec->create_sid;
6403 break;
6404 case LSM_ATTR_KEYCREATE:
6405 sid = tsec->keycreate_sid;
6406 break;
6407 case LSM_ATTR_SOCKCREATE:
6408 sid = tsec->sockcreate_sid;
6409 break;
6410 default:
6411 error = -EOPNOTSUPP;
6412 goto err_unlock;
6413 }
6414 rcu_read_unlock();
6415
6416 if (sid == SECSID_NULL) {
6417 *value = NULL;
6418 return 0;
6419 }
6420
6421 error = security_sid_to_context(sid, value, &len);
6422 if (error)
6423 return error;
6424 return len;
6425
6426err_unlock:
6427 rcu_read_unlock();
6428 return error;
6429}
6430
6431static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6432{
6433 struct task_security_struct *tsec;
6434 struct cred *new;
6435 u32 mysid = current_sid(), sid = 0, ptsid;
6436 int error;
6437 char *str = value;
6438
6439 /*
6440 * Basic control over ability to set these attributes at all.
6441 */
6442 switch (attr) {
6443 case LSM_ATTR_EXEC:
6444 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6445 PROCESS__SETEXEC, NULL);
6446 break;
6447 case LSM_ATTR_FSCREATE:
6448 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6449 PROCESS__SETFSCREATE, NULL);
6450 break;
6451 case LSM_ATTR_KEYCREATE:
6452 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6453 PROCESS__SETKEYCREATE, NULL);
6454 break;
6455 case LSM_ATTR_SOCKCREATE:
6456 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6457 PROCESS__SETSOCKCREATE, NULL);
6458 break;
6459 case LSM_ATTR_CURRENT:
6460 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6461 PROCESS__SETCURRENT, NULL);
6462 break;
6463 default:
6464 error = -EOPNOTSUPP;
6465 break;
6466 }
6467 if (error)
6468 return error;
6469
6470 /* Obtain a SID for the context, if one was specified. */
6471 if (size && str[0] && str[0] != '\n') {
6472 if (str[size-1] == '\n') {
6473 str[size-1] = 0;
6474 size--;
6475 }
6476 error = security_context_to_sid(value, size,
6477 &sid, GFP_KERNEL);
6478 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6479 if (!has_cap_mac_admin(true)) {
6480 struct audit_buffer *ab;
6481 size_t audit_size;
6482
6483 /* We strip a nul only if it is at the end,
6484 * otherwise the context contains a nul and
6485 * we should audit that */
6486 if (str[size - 1] == '\0')
6487 audit_size = size - 1;
6488 else
6489 audit_size = size;
6490 ab = audit_log_start(audit_context(),
6491 GFP_ATOMIC,
6492 AUDIT_SELINUX_ERR);
6493 if (!ab)
6494 return error;
6495 audit_log_format(ab, "op=fscreate invalid_context=");
6496 audit_log_n_untrustedstring(ab, value,
6497 audit_size);
6498 audit_log_end(ab);
6499
6500 return error;
6501 }
6502 error = security_context_to_sid_force(value, size,
6503 &sid);
6504 }
6505 if (error)
6506 return error;
6507 }
6508
6509 new = prepare_creds();
6510 if (!new)
6511 return -ENOMEM;
6512
6513 /* Permission checking based on the specified context is
6514 performed during the actual operation (execve,
6515 open/mkdir/...), when we know the full context of the
6516 operation. See selinux_bprm_creds_for_exec for the execve
6517 checks and may_create for the file creation checks. The
6518 operation will then fail if the context is not permitted. */
6519 tsec = selinux_cred(new);
6520 if (attr == LSM_ATTR_EXEC) {
6521 tsec->exec_sid = sid;
6522 } else if (attr == LSM_ATTR_FSCREATE) {
6523 tsec->create_sid = sid;
6524 } else if (attr == LSM_ATTR_KEYCREATE) {
6525 if (sid) {
6526 error = avc_has_perm(mysid, sid,
6527 SECCLASS_KEY, KEY__CREATE, NULL);
6528 if (error)
6529 goto abort_change;
6530 }
6531 tsec->keycreate_sid = sid;
6532 } else if (attr == LSM_ATTR_SOCKCREATE) {
6533 tsec->sockcreate_sid = sid;
6534 } else if (attr == LSM_ATTR_CURRENT) {
6535 error = -EINVAL;
6536 if (sid == 0)
6537 goto abort_change;
6538
6539 if (!current_is_single_threaded()) {
6540 error = security_bounded_transition(tsec->sid, sid);
6541 if (error)
6542 goto abort_change;
6543 }
6544
6545 /* Check permissions for the transition. */
6546 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6547 PROCESS__DYNTRANSITION, NULL);
6548 if (error)
6549 goto abort_change;
6550
6551 /* Check for ptracing, and update the task SID if ok.
6552 Otherwise, leave SID unchanged and fail. */
6553 ptsid = ptrace_parent_sid();
6554 if (ptsid != 0) {
6555 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6556 PROCESS__PTRACE, NULL);
6557 if (error)
6558 goto abort_change;
6559 }
6560
6561 tsec->sid = sid;
6562 } else {
6563 error = -EINVAL;
6564 goto abort_change;
6565 }
6566
6567 commit_creds(new);
6568 return size;
6569
6570abort_change:
6571 abort_creds(new);
6572 return error;
6573}
6574
6575/**
6576 * selinux_getselfattr - Get SELinux current task attributes
6577 * @attr: the requested attribute
6578 * @ctx: buffer to receive the result
6579 * @size: buffer size (input), buffer size used (output)
6580 * @flags: unused
6581 *
6582 * Fill the passed user space @ctx with the details of the requested
6583 * attribute.
6584 *
6585 * Returns the number of attributes on success, an error code otherwise.
6586 * There will only ever be one attribute.
6587 */
6588static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6589 u32 *size, u32 flags)
6590{
6591 int rc;
6592 char *val = NULL;
6593 int val_len;
6594
6595 val_len = selinux_lsm_getattr(attr, current, &val);
6596 if (val_len < 0)
6597 return val_len;
6598 rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6599 kfree(val);
6600 return (!rc ? 1 : rc);
6601}
6602
6603static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6604 u32 size, u32 flags)
6605{
6606 int rc;
6607
6608 rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6609 if (rc > 0)
6610 return 0;
6611 return rc;
6612}
6613
6614static int selinux_getprocattr(struct task_struct *p,
6615 const char *name, char **value)
6616{
6617 unsigned int attr = lsm_name_to_attr(name);
6618 int rc;
6619
6620 if (attr) {
6621 rc = selinux_lsm_getattr(attr, p, value);
6622 if (rc != -EOPNOTSUPP)
6623 return rc;
6624 }
6625
6626 return -EINVAL;
6627}
6628
6629static int selinux_setprocattr(const char *name, void *value, size_t size)
6630{
6631 int attr = lsm_name_to_attr(name);
6632
6633 if (attr)
6634 return selinux_lsm_setattr(attr, value, size);
6635 return -EINVAL;
6636}
6637
6638static int selinux_ismaclabel(const char *name)
6639{
6640 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6641}
6642
6643static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6644{
6645 return security_sid_to_context(secid, secdata, seclen);
6646}
6647
6648static int selinux_lsmprop_to_secctx(struct lsm_prop *prop, char **secdata,
6649 u32 *seclen)
6650{
6651 return selinux_secid_to_secctx(prop->selinux.secid, secdata, seclen);
6652}
6653
6654static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6655{
6656 return security_context_to_sid(secdata, seclen,
6657 secid, GFP_KERNEL);
6658}
6659
6660static void selinux_release_secctx(char *secdata, u32 seclen)
6661{
6662 kfree(secdata);
6663}
6664
6665static void selinux_inode_invalidate_secctx(struct inode *inode)
6666{
6667 struct inode_security_struct *isec = selinux_inode(inode);
6668
6669 spin_lock(&isec->lock);
6670 isec->initialized = LABEL_INVALID;
6671 spin_unlock(&isec->lock);
6672}
6673
6674/*
6675 * called with inode->i_mutex locked
6676 */
6677static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6678{
6679 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6680 ctx, ctxlen, 0);
6681 /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6682 return rc == -EOPNOTSUPP ? 0 : rc;
6683}
6684
6685/*
6686 * called with inode->i_mutex locked
6687 */
6688static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6689{
6690 return __vfs_setxattr_locked(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6691 ctx, ctxlen, 0, NULL);
6692}
6693
6694static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6695{
6696 int len = 0;
6697 len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6698 XATTR_SELINUX_SUFFIX, ctx, true);
6699 if (len < 0)
6700 return len;
6701 *ctxlen = len;
6702 return 0;
6703}
6704#ifdef CONFIG_KEYS
6705
6706static int selinux_key_alloc(struct key *k, const struct cred *cred,
6707 unsigned long flags)
6708{
6709 const struct task_security_struct *tsec;
6710 struct key_security_struct *ksec = selinux_key(k);
6711
6712 tsec = selinux_cred(cred);
6713 if (tsec->keycreate_sid)
6714 ksec->sid = tsec->keycreate_sid;
6715 else
6716 ksec->sid = tsec->sid;
6717
6718 return 0;
6719}
6720
6721static int selinux_key_permission(key_ref_t key_ref,
6722 const struct cred *cred,
6723 enum key_need_perm need_perm)
6724{
6725 struct key *key;
6726 struct key_security_struct *ksec;
6727 u32 perm, sid;
6728
6729 switch (need_perm) {
6730 case KEY_NEED_VIEW:
6731 perm = KEY__VIEW;
6732 break;
6733 case KEY_NEED_READ:
6734 perm = KEY__READ;
6735 break;
6736 case KEY_NEED_WRITE:
6737 perm = KEY__WRITE;
6738 break;
6739 case KEY_NEED_SEARCH:
6740 perm = KEY__SEARCH;
6741 break;
6742 case KEY_NEED_LINK:
6743 perm = KEY__LINK;
6744 break;
6745 case KEY_NEED_SETATTR:
6746 perm = KEY__SETATTR;
6747 break;
6748 case KEY_NEED_UNLINK:
6749 case KEY_SYSADMIN_OVERRIDE:
6750 case KEY_AUTHTOKEN_OVERRIDE:
6751 case KEY_DEFER_PERM_CHECK:
6752 return 0;
6753 default:
6754 WARN_ON(1);
6755 return -EPERM;
6756
6757 }
6758
6759 sid = cred_sid(cred);
6760 key = key_ref_to_ptr(key_ref);
6761 ksec = selinux_key(key);
6762
6763 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6764}
6765
6766static int selinux_key_getsecurity(struct key *key, char **_buffer)
6767{
6768 struct key_security_struct *ksec = selinux_key(key);
6769 char *context = NULL;
6770 unsigned len;
6771 int rc;
6772
6773 rc = security_sid_to_context(ksec->sid,
6774 &context, &len);
6775 if (!rc)
6776 rc = len;
6777 *_buffer = context;
6778 return rc;
6779}
6780
6781#ifdef CONFIG_KEY_NOTIFICATIONS
6782static int selinux_watch_key(struct key *key)
6783{
6784 struct key_security_struct *ksec = selinux_key(key);
6785 u32 sid = current_sid();
6786
6787 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6788}
6789#endif
6790#endif
6791
6792#ifdef CONFIG_SECURITY_INFINIBAND
6793static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
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_ibpkey_audit ibpkey;
6800
6801 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6802 if (err)
6803 return err;
6804
6805 ad.type = LSM_AUDIT_DATA_IBPKEY;
6806 ibpkey.subnet_prefix = subnet_prefix;
6807 ibpkey.pkey = pkey_val;
6808 ad.u.ibpkey = &ibpkey;
6809 return avc_has_perm(sec->sid, sid,
6810 SECCLASS_INFINIBAND_PKEY,
6811 INFINIBAND_PKEY__ACCESS, &ad);
6812}
6813
6814static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6815 u8 port_num)
6816{
6817 struct common_audit_data ad;
6818 int err;
6819 u32 sid = 0;
6820 struct ib_security_struct *sec = ib_sec;
6821 struct lsm_ibendport_audit ibendport;
6822
6823 err = security_ib_endport_sid(dev_name, port_num,
6824 &sid);
6825
6826 if (err)
6827 return err;
6828
6829 ad.type = LSM_AUDIT_DATA_IBENDPORT;
6830 ibendport.dev_name = dev_name;
6831 ibendport.port = port_num;
6832 ad.u.ibendport = &ibendport;
6833 return avc_has_perm(sec->sid, sid,
6834 SECCLASS_INFINIBAND_ENDPORT,
6835 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6836}
6837
6838static int selinux_ib_alloc_security(void *ib_sec)
6839{
6840 struct ib_security_struct *sec = selinux_ib(ib_sec);
6841
6842 sec->sid = current_sid();
6843 return 0;
6844}
6845#endif
6846
6847#ifdef CONFIG_BPF_SYSCALL
6848static int selinux_bpf(int cmd, union bpf_attr *attr,
6849 unsigned int size)
6850{
6851 u32 sid = current_sid();
6852 int ret;
6853
6854 switch (cmd) {
6855 case BPF_MAP_CREATE:
6856 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6857 NULL);
6858 break;
6859 case BPF_PROG_LOAD:
6860 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6861 NULL);
6862 break;
6863 default:
6864 ret = 0;
6865 break;
6866 }
6867
6868 return ret;
6869}
6870
6871static u32 bpf_map_fmode_to_av(fmode_t fmode)
6872{
6873 u32 av = 0;
6874
6875 if (fmode & FMODE_READ)
6876 av |= BPF__MAP_READ;
6877 if (fmode & FMODE_WRITE)
6878 av |= BPF__MAP_WRITE;
6879 return av;
6880}
6881
6882/* This function will check the file pass through unix socket or binder to see
6883 * if it is a bpf related object. And apply corresponding checks on the bpf
6884 * object based on the type. The bpf maps and programs, not like other files and
6885 * socket, are using a shared anonymous inode inside the kernel as their inode.
6886 * So checking that inode cannot identify if the process have privilege to
6887 * access the bpf object and that's why we have to add this additional check in
6888 * selinux_file_receive and selinux_binder_transfer_files.
6889 */
6890static int bpf_fd_pass(const struct file *file, u32 sid)
6891{
6892 struct bpf_security_struct *bpfsec;
6893 struct bpf_prog *prog;
6894 struct bpf_map *map;
6895 int ret;
6896
6897 if (file->f_op == &bpf_map_fops) {
6898 map = file->private_data;
6899 bpfsec = map->security;
6900 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6901 bpf_map_fmode_to_av(file->f_mode), NULL);
6902 if (ret)
6903 return ret;
6904 } else if (file->f_op == &bpf_prog_fops) {
6905 prog = file->private_data;
6906 bpfsec = prog->aux->security;
6907 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6908 BPF__PROG_RUN, NULL);
6909 if (ret)
6910 return ret;
6911 }
6912 return 0;
6913}
6914
6915static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6916{
6917 u32 sid = current_sid();
6918 struct bpf_security_struct *bpfsec;
6919
6920 bpfsec = map->security;
6921 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6922 bpf_map_fmode_to_av(fmode), NULL);
6923}
6924
6925static int selinux_bpf_prog(struct bpf_prog *prog)
6926{
6927 u32 sid = current_sid();
6928 struct bpf_security_struct *bpfsec;
6929
6930 bpfsec = prog->aux->security;
6931 return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6932 BPF__PROG_RUN, NULL);
6933}
6934
6935static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
6936 struct bpf_token *token)
6937{
6938 struct bpf_security_struct *bpfsec;
6939
6940 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6941 if (!bpfsec)
6942 return -ENOMEM;
6943
6944 bpfsec->sid = current_sid();
6945 map->security = bpfsec;
6946
6947 return 0;
6948}
6949
6950static void selinux_bpf_map_free(struct bpf_map *map)
6951{
6952 struct bpf_security_struct *bpfsec = map->security;
6953
6954 map->security = NULL;
6955 kfree(bpfsec);
6956}
6957
6958static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
6959 struct bpf_token *token)
6960{
6961 struct bpf_security_struct *bpfsec;
6962
6963 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6964 if (!bpfsec)
6965 return -ENOMEM;
6966
6967 bpfsec->sid = current_sid();
6968 prog->aux->security = bpfsec;
6969
6970 return 0;
6971}
6972
6973static void selinux_bpf_prog_free(struct bpf_prog *prog)
6974{
6975 struct bpf_security_struct *bpfsec = prog->aux->security;
6976
6977 prog->aux->security = NULL;
6978 kfree(bpfsec);
6979}
6980
6981static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
6982 const struct path *path)
6983{
6984 struct bpf_security_struct *bpfsec;
6985
6986 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6987 if (!bpfsec)
6988 return -ENOMEM;
6989
6990 bpfsec->sid = current_sid();
6991 token->security = bpfsec;
6992
6993 return 0;
6994}
6995
6996static void selinux_bpf_token_free(struct bpf_token *token)
6997{
6998 struct bpf_security_struct *bpfsec = token->security;
6999
7000 token->security = NULL;
7001 kfree(bpfsec);
7002}
7003#endif
7004
7005struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
7006 .lbs_cred = sizeof(struct task_security_struct),
7007 .lbs_file = sizeof(struct file_security_struct),
7008 .lbs_inode = sizeof(struct inode_security_struct),
7009 .lbs_ipc = sizeof(struct ipc_security_struct),
7010 .lbs_key = sizeof(struct key_security_struct),
7011 .lbs_msg_msg = sizeof(struct msg_security_struct),
7012#ifdef CONFIG_PERF_EVENTS
7013 .lbs_perf_event = sizeof(struct perf_event_security_struct),
7014#endif
7015 .lbs_sock = sizeof(struct sk_security_struct),
7016 .lbs_superblock = sizeof(struct superblock_security_struct),
7017 .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
7018 .lbs_tun_dev = sizeof(struct tun_security_struct),
7019 .lbs_ib = sizeof(struct ib_security_struct),
7020};
7021
7022#ifdef CONFIG_PERF_EVENTS
7023static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
7024{
7025 u32 requested, sid = current_sid();
7026
7027 if (type == PERF_SECURITY_OPEN)
7028 requested = PERF_EVENT__OPEN;
7029 else if (type == PERF_SECURITY_CPU)
7030 requested = PERF_EVENT__CPU;
7031 else if (type == PERF_SECURITY_KERNEL)
7032 requested = PERF_EVENT__KERNEL;
7033 else if (type == PERF_SECURITY_TRACEPOINT)
7034 requested = PERF_EVENT__TRACEPOINT;
7035 else
7036 return -EINVAL;
7037
7038 return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
7039 requested, NULL);
7040}
7041
7042static int selinux_perf_event_alloc(struct perf_event *event)
7043{
7044 struct perf_event_security_struct *perfsec;
7045
7046 perfsec = selinux_perf_event(event->security);
7047 perfsec->sid = current_sid();
7048
7049 return 0;
7050}
7051
7052static int selinux_perf_event_read(struct perf_event *event)
7053{
7054 struct perf_event_security_struct *perfsec = event->security;
7055 u32 sid = current_sid();
7056
7057 return avc_has_perm(sid, perfsec->sid,
7058 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7059}
7060
7061static int selinux_perf_event_write(struct perf_event *event)
7062{
7063 struct perf_event_security_struct *perfsec = event->security;
7064 u32 sid = current_sid();
7065
7066 return avc_has_perm(sid, perfsec->sid,
7067 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7068}
7069#endif
7070
7071#ifdef CONFIG_IO_URING
7072/**
7073 * selinux_uring_override_creds - check the requested cred override
7074 * @new: the target creds
7075 *
7076 * Check to see if the current task is allowed to override it's credentials
7077 * to service an io_uring operation.
7078 */
7079static int selinux_uring_override_creds(const struct cred *new)
7080{
7081 return avc_has_perm(current_sid(), cred_sid(new),
7082 SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7083}
7084
7085/**
7086 * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7087 *
7088 * Check to see if the current task is allowed to create a new io_uring
7089 * kernel polling thread.
7090 */
7091static int selinux_uring_sqpoll(void)
7092{
7093 u32 sid = current_sid();
7094
7095 return avc_has_perm(sid, sid,
7096 SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7097}
7098
7099/**
7100 * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7101 * @ioucmd: the io_uring command structure
7102 *
7103 * Check to see if the current domain is allowed to execute an
7104 * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7105 *
7106 */
7107static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7108{
7109 struct file *file = ioucmd->file;
7110 struct inode *inode = file_inode(file);
7111 struct inode_security_struct *isec = selinux_inode(inode);
7112 struct common_audit_data ad;
7113
7114 ad.type = LSM_AUDIT_DATA_FILE;
7115 ad.u.file = file;
7116
7117 return avc_has_perm(current_sid(), isec->sid,
7118 SECCLASS_IO_URING, IO_URING__CMD, &ad);
7119}
7120#endif /* CONFIG_IO_URING */
7121
7122static const struct lsm_id selinux_lsmid = {
7123 .name = "selinux",
7124 .id = LSM_ID_SELINUX,
7125};
7126
7127/*
7128 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7129 * 1. any hooks that don't belong to (2.) or (3.) below,
7130 * 2. hooks that both access structures allocated by other hooks, and allocate
7131 * structures that can be later accessed by other hooks (mostly "cloning"
7132 * hooks),
7133 * 3. hooks that only allocate structures that can be later accessed by other
7134 * hooks ("allocating" hooks).
7135 *
7136 * Please follow block comment delimiters in the list to keep this order.
7137 */
7138static struct security_hook_list selinux_hooks[] __ro_after_init = {
7139 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7140 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7141 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7142 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7143
7144 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7145 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7146 LSM_HOOK_INIT(capget, selinux_capget),
7147 LSM_HOOK_INIT(capset, selinux_capset),
7148 LSM_HOOK_INIT(capable, selinux_capable),
7149 LSM_HOOK_INIT(quotactl, selinux_quotactl),
7150 LSM_HOOK_INIT(quota_on, selinux_quota_on),
7151 LSM_HOOK_INIT(syslog, selinux_syslog),
7152 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7153
7154 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7155
7156 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7157 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7158 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7159
7160 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7161 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7162 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7163 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7164 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7165 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7166 LSM_HOOK_INIT(sb_mount, selinux_mount),
7167 LSM_HOOK_INIT(sb_umount, selinux_umount),
7168 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7169 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7170
7171 LSM_HOOK_INIT(move_mount, selinux_move_mount),
7172
7173 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7174 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7175
7176 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7177 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7178 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7179 LSM_HOOK_INIT(inode_create, selinux_inode_create),
7180 LSM_HOOK_INIT(inode_link, selinux_inode_link),
7181 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7182 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7183 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7184 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7185 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7186 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7187 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7188 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7189 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7190 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7191 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7192 LSM_HOOK_INIT(inode_xattr_skipcap, selinux_inode_xattr_skipcap),
7193 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7194 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7195 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7196 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7197 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7198 LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7199 LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7200 LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7201 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7202 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7203 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7204 LSM_HOOK_INIT(inode_getlsmprop, selinux_inode_getlsmprop),
7205 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7206 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7207 LSM_HOOK_INIT(path_notify, selinux_path_notify),
7208
7209 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7210
7211 LSM_HOOK_INIT(file_permission, selinux_file_permission),
7212 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7213 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7214 LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7215 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7216 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7217 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7218 LSM_HOOK_INIT(file_lock, selinux_file_lock),
7219 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7220 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7221 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7222 LSM_HOOK_INIT(file_receive, selinux_file_receive),
7223
7224 LSM_HOOK_INIT(file_open, selinux_file_open),
7225
7226 LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7227 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7228 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7229 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7230 LSM_HOOK_INIT(cred_getlsmprop, selinux_cred_getlsmprop),
7231 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7232 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7233 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7234 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7235 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7236 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7237 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7238 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7239 LSM_HOOK_INIT(current_getlsmprop_subj, selinux_current_getlsmprop_subj),
7240 LSM_HOOK_INIT(task_getlsmprop_obj, selinux_task_getlsmprop_obj),
7241 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7242 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7243 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7244 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7245 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7246 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7247 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7248 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7249 LSM_HOOK_INIT(task_kill, selinux_task_kill),
7250 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7251 LSM_HOOK_INIT(userns_create, selinux_userns_create),
7252
7253 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7254 LSM_HOOK_INIT(ipc_getlsmprop, selinux_ipc_getlsmprop),
7255
7256 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7257 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7258 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7259 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7260
7261 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7262 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7263 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7264
7265 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7266 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7267 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7268
7269 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7270
7271 LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7272 LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7273 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7274 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7275
7276 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7277 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7278 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7279 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7280 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7281 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7282
7283 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7284 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7285
7286 LSM_HOOK_INIT(socket_create, selinux_socket_create),
7287 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7288 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7289 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7290 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7291 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7292 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7293 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7294 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7295 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7296 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7297 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7298 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7299 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7300 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7301 LSM_HOOK_INIT(socket_getpeersec_stream,
7302 selinux_socket_getpeersec_stream),
7303 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7304 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7305 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7306 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7307 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7308 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7309 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7310 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7311 LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7312 LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7313 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7314 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7315 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7316 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7317 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7318 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7319 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7320 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7321 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7322 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7323 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7324#ifdef CONFIG_SECURITY_INFINIBAND
7325 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7326 LSM_HOOK_INIT(ib_endport_manage_subnet,
7327 selinux_ib_endport_manage_subnet),
7328#endif
7329#ifdef CONFIG_SECURITY_NETWORK_XFRM
7330 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7331 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7332 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7333 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7334 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7335 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7336 selinux_xfrm_state_pol_flow_match),
7337 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7338#endif
7339
7340#ifdef CONFIG_KEYS
7341 LSM_HOOK_INIT(key_permission, selinux_key_permission),
7342 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7343#ifdef CONFIG_KEY_NOTIFICATIONS
7344 LSM_HOOK_INIT(watch_key, selinux_watch_key),
7345#endif
7346#endif
7347
7348#ifdef CONFIG_AUDIT
7349 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7350 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7351 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7352#endif
7353
7354#ifdef CONFIG_BPF_SYSCALL
7355 LSM_HOOK_INIT(bpf, selinux_bpf),
7356 LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7357 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7358 LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free),
7359 LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free),
7360 LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free),
7361#endif
7362
7363#ifdef CONFIG_PERF_EVENTS
7364 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7365 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7366 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7367#endif
7368
7369#ifdef CONFIG_IO_URING
7370 LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7371 LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7372 LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7373#endif
7374
7375 /*
7376 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7377 */
7378 LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7379 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7380 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7381 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7382#ifdef CONFIG_SECURITY_NETWORK_XFRM
7383 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7384#endif
7385
7386 /*
7387 * PUT "ALLOCATING" HOOKS HERE
7388 */
7389 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7390 LSM_HOOK_INIT(msg_queue_alloc_security,
7391 selinux_msg_queue_alloc_security),
7392 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7393 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7394 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7395 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7396 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7397 LSM_HOOK_INIT(lsmprop_to_secctx, selinux_lsmprop_to_secctx),
7398 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7399 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7400 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7401#ifdef CONFIG_SECURITY_INFINIBAND
7402 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7403#endif
7404#ifdef CONFIG_SECURITY_NETWORK_XFRM
7405 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7406 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7407 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7408 selinux_xfrm_state_alloc_acquire),
7409#endif
7410#ifdef CONFIG_KEYS
7411 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7412#endif
7413#ifdef CONFIG_AUDIT
7414 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7415#endif
7416#ifdef CONFIG_BPF_SYSCALL
7417 LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create),
7418 LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load),
7419 LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create),
7420#endif
7421#ifdef CONFIG_PERF_EVENTS
7422 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7423#endif
7424};
7425
7426static __init int selinux_init(void)
7427{
7428 pr_info("SELinux: Initializing.\n");
7429
7430 memset(&selinux_state, 0, sizeof(selinux_state));
7431 enforcing_set(selinux_enforcing_boot);
7432 selinux_avc_init();
7433 mutex_init(&selinux_state.status_lock);
7434 mutex_init(&selinux_state.policy_mutex);
7435
7436 /* Set the security state for the initial task. */
7437 cred_init_security();
7438
7439 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7440 if (!default_noexec)
7441 pr_notice("SELinux: virtual memory is executable by default\n");
7442
7443 avc_init();
7444
7445 avtab_cache_init();
7446
7447 ebitmap_cache_init();
7448
7449 hashtab_cache_init();
7450
7451 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7452 &selinux_lsmid);
7453
7454 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7455 panic("SELinux: Unable to register AVC netcache callback\n");
7456
7457 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7458 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7459
7460 if (selinux_enforcing_boot)
7461 pr_debug("SELinux: Starting in enforcing mode\n");
7462 else
7463 pr_debug("SELinux: Starting in permissive mode\n");
7464
7465 fs_validate_description("selinux", selinux_fs_parameters);
7466
7467 return 0;
7468}
7469
7470static void delayed_superblock_init(struct super_block *sb, void *unused)
7471{
7472 selinux_set_mnt_opts(sb, NULL, 0, NULL);
7473}
7474
7475void selinux_complete_init(void)
7476{
7477 pr_debug("SELinux: Completing initialization.\n");
7478
7479 /* Set up any superblocks initialized prior to the policy load. */
7480 pr_debug("SELinux: Setting up existing superblocks.\n");
7481 iterate_supers(delayed_superblock_init, NULL);
7482}
7483
7484/* SELinux requires early initialization in order to label
7485 all processes and objects when they are created. */
7486DEFINE_LSM(selinux) = {
7487 .name = "selinux",
7488 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7489 .enabled = &selinux_enabled_boot,
7490 .blobs = &selinux_blob_sizes,
7491 .init = selinux_init,
7492};
7493
7494#if defined(CONFIG_NETFILTER)
7495static const struct nf_hook_ops selinux_nf_ops[] = {
7496 {
7497 .hook = selinux_ip_postroute,
7498 .pf = NFPROTO_IPV4,
7499 .hooknum = NF_INET_POST_ROUTING,
7500 .priority = NF_IP_PRI_SELINUX_LAST,
7501 },
7502 {
7503 .hook = selinux_ip_forward,
7504 .pf = NFPROTO_IPV4,
7505 .hooknum = NF_INET_FORWARD,
7506 .priority = NF_IP_PRI_SELINUX_FIRST,
7507 },
7508 {
7509 .hook = selinux_ip_output,
7510 .pf = NFPROTO_IPV4,
7511 .hooknum = NF_INET_LOCAL_OUT,
7512 .priority = NF_IP_PRI_SELINUX_FIRST,
7513 },
7514#if IS_ENABLED(CONFIG_IPV6)
7515 {
7516 .hook = selinux_ip_postroute,
7517 .pf = NFPROTO_IPV6,
7518 .hooknum = NF_INET_POST_ROUTING,
7519 .priority = NF_IP6_PRI_SELINUX_LAST,
7520 },
7521 {
7522 .hook = selinux_ip_forward,
7523 .pf = NFPROTO_IPV6,
7524 .hooknum = NF_INET_FORWARD,
7525 .priority = NF_IP6_PRI_SELINUX_FIRST,
7526 },
7527 {
7528 .hook = selinux_ip_output,
7529 .pf = NFPROTO_IPV6,
7530 .hooknum = NF_INET_LOCAL_OUT,
7531 .priority = NF_IP6_PRI_SELINUX_FIRST,
7532 },
7533#endif /* IPV6 */
7534};
7535
7536static int __net_init selinux_nf_register(struct net *net)
7537{
7538 return nf_register_net_hooks(net, selinux_nf_ops,
7539 ARRAY_SIZE(selinux_nf_ops));
7540}
7541
7542static void __net_exit selinux_nf_unregister(struct net *net)
7543{
7544 nf_unregister_net_hooks(net, selinux_nf_ops,
7545 ARRAY_SIZE(selinux_nf_ops));
7546}
7547
7548static struct pernet_operations selinux_net_ops = {
7549 .init = selinux_nf_register,
7550 .exit = selinux_nf_unregister,
7551};
7552
7553static int __init selinux_nf_ip_init(void)
7554{
7555 int err;
7556
7557 if (!selinux_enabled_boot)
7558 return 0;
7559
7560 pr_debug("SELinux: Registering netfilter hooks\n");
7561
7562 err = register_pernet_subsys(&selinux_net_ops);
7563 if (err)
7564 panic("SELinux: register_pernet_subsys: error %d\n", err);
7565
7566 return 0;
7567}
7568__initcall(selinux_nf_ip_init);
7569#endif /* CONFIG_NETFILTER */