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