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binder: use cred instead of task for selinux checks
[mirror_ubuntu-jammy-kernel.git] / security / selinux / hooks.c
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/kernel_read_file.h>
28 #include <linux/tracehook.h>
29 #include <linux/errno.h>
30 #include <linux/sched/signal.h>
31 #include <linux/sched/task.h>
32 #include <linux/lsm_hooks.h>
33 #include <linux/xattr.h>
34 #include <linux/capability.h>
35 #include <linux/unistd.h>
36 #include <linux/mm.h>
37 #include <linux/mman.h>
38 #include <linux/slab.h>
39 #include <linux/pagemap.h>
40 #include <linux/proc_fs.h>
41 #include <linux/swap.h>
42 #include <linux/spinlock.h>
43 #include <linux/syscalls.h>
44 #include <linux/dcache.h>
45 #include <linux/file.h>
46 #include <linux/fdtable.h>
47 #include <linux/namei.h>
48 #include <linux/mount.h>
49 #include <linux/fs_context.h>
50 #include <linux/fs_parser.h>
51 #include <linux/netfilter_ipv4.h>
52 #include <linux/netfilter_ipv6.h>
53 #include <linux/tty.h>
54 #include <net/icmp.h>
55 #include <net/ip.h> /* for local_port_range[] */
56 #include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
57 #include <net/inet_connection_sock.h>
58 #include <net/net_namespace.h>
59 #include <net/netlabel.h>
60 #include <linux/uaccess.h>
61 #include <asm/ioctls.h>
62 #include <linux/atomic.h>
63 #include <linux/bitops.h>
64 #include <linux/interrupt.h>
65 #include <linux/netdevice.h> /* for network interface checks */
66 #include <net/netlink.h>
67 #include <linux/tcp.h>
68 #include <linux/udp.h>
69 #include <linux/dccp.h>
70 #include <linux/sctp.h>
71 #include <net/sctp/structs.h>
72 #include <linux/quota.h>
73 #include <linux/un.h> /* for Unix socket types */
74 #include <net/af_unix.h> /* for Unix socket types */
75 #include <linux/parser.h>
76 #include <linux/nfs_mount.h>
77 #include <net/ipv6.h>
78 #include <linux/hugetlb.h>
79 #include <linux/personality.h>
80 #include <linux/audit.h>
81 #include <linux/string.h>
82 #include <linux/mutex.h>
83 #include <linux/posix-timers.h>
84 #include <linux/syslog.h>
85 #include <linux/user_namespace.h>
86 #include <linux/export.h>
87 #include <linux/msg.h>
88 #include <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
96 #include "avc.h"
97 #include "objsec.h"
98 #include "netif.h"
99 #include "netnode.h"
100 #include "netport.h"
101 #include "ibpkey.h"
102 #include "xfrm.h"
103 #include "netlabel.h"
104 #include "audit.h"
105 #include "avc_ss.h"
106
107 struct selinux_state selinux_state;
108
109 /* SECMARK reference count */
110 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
111
112 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
113 static int selinux_enforcing_boot __initdata;
114
115 static int __init enforcing_setup(char *str)
116 {
117 unsigned long enforcing;
118 if (!kstrtoul(str, 0, &enforcing))
119 selinux_enforcing_boot = enforcing ? 1 : 0;
120 return 1;
121 }
122 __setup("enforcing=", enforcing_setup);
123 #else
124 #define selinux_enforcing_boot 1
125 #endif
126
127 int selinux_enabled_boot __initdata = 1;
128 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
129 static int __init selinux_enabled_setup(char *str)
130 {
131 unsigned long enabled;
132 if (!kstrtoul(str, 0, &enabled))
133 selinux_enabled_boot = enabled ? 1 : 0;
134 return 1;
135 }
136 __setup("selinux=", selinux_enabled_setup);
137 #endif
138
139 static unsigned int selinux_checkreqprot_boot =
140 CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
141
142 static int __init checkreqprot_setup(char *str)
143 {
144 unsigned long checkreqprot;
145
146 if (!kstrtoul(str, 0, &checkreqprot)) {
147 selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
148 if (checkreqprot)
149 pr_warn("SELinux: checkreqprot set to 1 via kernel parameter. This is deprecated and will be rejected in a future kernel release.\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 */
166 static 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 */
182 static int selinux_peerlbl_enabled(void)
183 {
184 return (selinux_policycap_alwaysnetwork() ||
185 netlbl_enabled() || selinux_xfrm_enabled());
186 }
187
188 static 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
199 static 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 */
212 static void cred_init_security(void)
213 {
214 struct cred *cred = (struct cred *) current->real_cred;
215 struct task_security_struct *tsec;
216
217 tsec = selinux_cred(cred);
218 tsec->osid = tsec->sid = SECINITSID_KERNEL;
219 }
220
221 /*
222 * get the security ID of a set of credentials
223 */
224 static inline u32 cred_sid(const struct cred *cred)
225 {
226 const struct task_security_struct *tsec;
227
228 tsec = selinux_cred(cred);
229 return tsec->sid;
230 }
231
232 /*
233 * get the subjective security ID of a task
234 */
235 static inline u32 task_sid_subj(const struct task_struct *task)
236 {
237 u32 sid;
238
239 rcu_read_lock();
240 sid = cred_sid(rcu_dereference(task->cred));
241 rcu_read_unlock();
242 return sid;
243 }
244
245 /*
246 * get the objective security ID of a task
247 */
248 static inline u32 task_sid_obj(const struct task_struct *task)
249 {
250 u32 sid;
251
252 rcu_read_lock();
253 sid = cred_sid(__task_cred(task));
254 rcu_read_unlock();
255 return sid;
256 }
257
258 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
259
260 /*
261 * Try reloading inode security labels that have been marked as invalid. The
262 * @may_sleep parameter indicates when sleeping and thus reloading labels is
263 * allowed; when set to false, returns -ECHILD when the label is
264 * invalid. The @dentry parameter should be set to a dentry of the inode.
265 */
266 static int __inode_security_revalidate(struct inode *inode,
267 struct dentry *dentry,
268 bool may_sleep)
269 {
270 struct inode_security_struct *isec = selinux_inode(inode);
271
272 might_sleep_if(may_sleep);
273
274 if (selinux_initialized(&selinux_state) &&
275 isec->initialized != LABEL_INITIALIZED) {
276 if (!may_sleep)
277 return -ECHILD;
278
279 /*
280 * Try reloading the inode security label. This will fail if
281 * @opt_dentry is NULL and no dentry for this inode can be
282 * found; in that case, continue using the old label.
283 */
284 inode_doinit_with_dentry(inode, dentry);
285 }
286 return 0;
287 }
288
289 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
290 {
291 return selinux_inode(inode);
292 }
293
294 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
295 {
296 int error;
297
298 error = __inode_security_revalidate(inode, NULL, !rcu);
299 if (error)
300 return ERR_PTR(error);
301 return selinux_inode(inode);
302 }
303
304 /*
305 * Get the security label of an inode.
306 */
307 static struct inode_security_struct *inode_security(struct inode *inode)
308 {
309 __inode_security_revalidate(inode, NULL, true);
310 return selinux_inode(inode);
311 }
312
313 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
314 {
315 struct inode *inode = d_backing_inode(dentry);
316
317 return selinux_inode(inode);
318 }
319
320 /*
321 * Get the security label of a dentry's backing inode.
322 */
323 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
324 {
325 struct inode *inode = d_backing_inode(dentry);
326
327 __inode_security_revalidate(inode, dentry, true);
328 return selinux_inode(inode);
329 }
330
331 static void inode_free_security(struct inode *inode)
332 {
333 struct inode_security_struct *isec = selinux_inode(inode);
334 struct superblock_security_struct *sbsec;
335
336 if (!isec)
337 return;
338 sbsec = selinux_superblock(inode->i_sb);
339 /*
340 * As not all inode security structures are in a list, we check for
341 * empty list outside of the lock to make sure that we won't waste
342 * time taking a lock doing nothing.
343 *
344 * The list_del_init() function can be safely called more than once.
345 * It should not be possible for this function to be called with
346 * concurrent list_add(), but for better safety against future changes
347 * in the code, we use list_empty_careful() here.
348 */
349 if (!list_empty_careful(&isec->list)) {
350 spin_lock(&sbsec->isec_lock);
351 list_del_init(&isec->list);
352 spin_unlock(&sbsec->isec_lock);
353 }
354 }
355
356 struct selinux_mnt_opts {
357 const char *fscontext, *context, *rootcontext, *defcontext;
358 };
359
360 static void selinux_free_mnt_opts(void *mnt_opts)
361 {
362 struct selinux_mnt_opts *opts = mnt_opts;
363 kfree(opts->fscontext);
364 kfree(opts->context);
365 kfree(opts->rootcontext);
366 kfree(opts->defcontext);
367 kfree(opts);
368 }
369
370 enum {
371 Opt_error = -1,
372 Opt_context = 0,
373 Opt_defcontext = 1,
374 Opt_fscontext = 2,
375 Opt_rootcontext = 3,
376 Opt_seclabel = 4,
377 };
378
379 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
380 static struct {
381 const char *name;
382 int len;
383 int opt;
384 bool has_arg;
385 } tokens[] = {
386 A(context, true),
387 A(fscontext, true),
388 A(defcontext, true),
389 A(rootcontext, true),
390 A(seclabel, false),
391 };
392 #undef A
393
394 static int match_opt_prefix(char *s, int l, char **arg)
395 {
396 int i;
397
398 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
399 size_t len = tokens[i].len;
400 if (len > l || memcmp(s, tokens[i].name, len))
401 continue;
402 if (tokens[i].has_arg) {
403 if (len == l || s[len] != '=')
404 continue;
405 *arg = s + len + 1;
406 } else if (len != l)
407 continue;
408 return tokens[i].opt;
409 }
410 return Opt_error;
411 }
412
413 #define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
414
415 static int may_context_mount_sb_relabel(u32 sid,
416 struct superblock_security_struct *sbsec,
417 const struct cred *cred)
418 {
419 const struct task_security_struct *tsec = selinux_cred(cred);
420 int rc;
421
422 rc = avc_has_perm(&selinux_state,
423 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
424 FILESYSTEM__RELABELFROM, NULL);
425 if (rc)
426 return rc;
427
428 rc = avc_has_perm(&selinux_state,
429 tsec->sid, sid, SECCLASS_FILESYSTEM,
430 FILESYSTEM__RELABELTO, NULL);
431 return rc;
432 }
433
434 static int may_context_mount_inode_relabel(u32 sid,
435 struct superblock_security_struct *sbsec,
436 const struct cred *cred)
437 {
438 const struct task_security_struct *tsec = selinux_cred(cred);
439 int rc;
440 rc = avc_has_perm(&selinux_state,
441 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
442 FILESYSTEM__RELABELFROM, NULL);
443 if (rc)
444 return rc;
445
446 rc = avc_has_perm(&selinux_state,
447 sid, sbsec->sid, SECCLASS_FILESYSTEM,
448 FILESYSTEM__ASSOCIATE, NULL);
449 return rc;
450 }
451
452 static int selinux_is_genfs_special_handling(struct super_block *sb)
453 {
454 /* Special handling. Genfs but also in-core setxattr handler */
455 return !strcmp(sb->s_type->name, "sysfs") ||
456 !strcmp(sb->s_type->name, "pstore") ||
457 !strcmp(sb->s_type->name, "debugfs") ||
458 !strcmp(sb->s_type->name, "tracefs") ||
459 !strcmp(sb->s_type->name, "rootfs") ||
460 (selinux_policycap_cgroupseclabel() &&
461 (!strcmp(sb->s_type->name, "cgroup") ||
462 !strcmp(sb->s_type->name, "cgroup2")));
463 }
464
465 static int selinux_is_sblabel_mnt(struct super_block *sb)
466 {
467 struct superblock_security_struct *sbsec = selinux_superblock(sb);
468
469 /*
470 * IMPORTANT: Double-check logic in this function when adding a new
471 * SECURITY_FS_USE_* definition!
472 */
473 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
474
475 switch (sbsec->behavior) {
476 case SECURITY_FS_USE_XATTR:
477 case SECURITY_FS_USE_TRANS:
478 case SECURITY_FS_USE_TASK:
479 case SECURITY_FS_USE_NATIVE:
480 return 1;
481
482 case SECURITY_FS_USE_GENFS:
483 return selinux_is_genfs_special_handling(sb);
484
485 /* Never allow relabeling on context mounts */
486 case SECURITY_FS_USE_MNTPOINT:
487 case SECURITY_FS_USE_NONE:
488 default:
489 return 0;
490 }
491 }
492
493 static int sb_check_xattr_support(struct super_block *sb)
494 {
495 struct superblock_security_struct *sbsec = sb->s_security;
496 struct dentry *root = sb->s_root;
497 struct inode *root_inode = d_backing_inode(root);
498 u32 sid;
499 int rc;
500
501 /*
502 * Make sure that the xattr handler exists and that no
503 * error other than -ENODATA is returned by getxattr on
504 * the root directory. -ENODATA is ok, as this may be
505 * the first boot of the SELinux kernel before we have
506 * assigned xattr values to the filesystem.
507 */
508 if (!(root_inode->i_opflags & IOP_XATTR)) {
509 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
510 sb->s_id, sb->s_type->name);
511 goto fallback;
512 }
513
514 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
515 if (rc < 0 && rc != -ENODATA) {
516 if (rc == -EOPNOTSUPP) {
517 pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
518 sb->s_id, sb->s_type->name);
519 goto fallback;
520 } else {
521 pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
522 sb->s_id, sb->s_type->name, -rc);
523 return rc;
524 }
525 }
526 return 0;
527
528 fallback:
529 /* No xattr support - try to fallback to genfs if possible. */
530 rc = security_genfs_sid(&selinux_state, sb->s_type->name, "/",
531 SECCLASS_DIR, &sid);
532 if (rc)
533 return -EOPNOTSUPP;
534
535 pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
536 sb->s_id, sb->s_type->name);
537 sbsec->behavior = SECURITY_FS_USE_GENFS;
538 sbsec->sid = sid;
539 return 0;
540 }
541
542 static int sb_finish_set_opts(struct super_block *sb)
543 {
544 struct superblock_security_struct *sbsec = selinux_superblock(sb);
545 struct dentry *root = sb->s_root;
546 struct inode *root_inode = d_backing_inode(root);
547 int rc = 0;
548
549 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
550 rc = sb_check_xattr_support(sb);
551 if (rc)
552 return rc;
553 }
554
555 sbsec->flags |= SE_SBINITIALIZED;
556
557 /*
558 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply
559 * leave the flag untouched because sb_clone_mnt_opts might be handing
560 * us a superblock that needs the flag to be cleared.
561 */
562 if (selinux_is_sblabel_mnt(sb))
563 sbsec->flags |= SBLABEL_MNT;
564 else
565 sbsec->flags &= ~SBLABEL_MNT;
566
567 /* Initialize the root inode. */
568 rc = inode_doinit_with_dentry(root_inode, root);
569
570 /* Initialize any other inodes associated with the superblock, e.g.
571 inodes created prior to initial policy load or inodes created
572 during get_sb by a pseudo filesystem that directly
573 populates itself. */
574 spin_lock(&sbsec->isec_lock);
575 while (!list_empty(&sbsec->isec_head)) {
576 struct inode_security_struct *isec =
577 list_first_entry(&sbsec->isec_head,
578 struct inode_security_struct, list);
579 struct inode *inode = isec->inode;
580 list_del_init(&isec->list);
581 spin_unlock(&sbsec->isec_lock);
582 inode = igrab(inode);
583 if (inode) {
584 if (!IS_PRIVATE(inode))
585 inode_doinit_with_dentry(inode, NULL);
586 iput(inode);
587 }
588 spin_lock(&sbsec->isec_lock);
589 }
590 spin_unlock(&sbsec->isec_lock);
591 return rc;
592 }
593
594 static int bad_option(struct superblock_security_struct *sbsec, char flag,
595 u32 old_sid, u32 new_sid)
596 {
597 char mnt_flags = sbsec->flags & SE_MNTMASK;
598
599 /* check if the old mount command had the same options */
600 if (sbsec->flags & SE_SBINITIALIZED)
601 if (!(sbsec->flags & flag) ||
602 (old_sid != new_sid))
603 return 1;
604
605 /* check if we were passed the same options twice,
606 * aka someone passed context=a,context=b
607 */
608 if (!(sbsec->flags & SE_SBINITIALIZED))
609 if (mnt_flags & flag)
610 return 1;
611 return 0;
612 }
613
614 static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
615 {
616 int rc = security_context_str_to_sid(&selinux_state, s,
617 sid, GFP_KERNEL);
618 if (rc)
619 pr_warn("SELinux: security_context_str_to_sid"
620 "(%s) failed for (dev %s, type %s) errno=%d\n",
621 s, sb->s_id, sb->s_type->name, rc);
622 return rc;
623 }
624
625 /*
626 * Allow filesystems with binary mount data to explicitly set mount point
627 * labeling information.
628 */
629 static int selinux_set_mnt_opts(struct super_block *sb,
630 void *mnt_opts,
631 unsigned long kern_flags,
632 unsigned long *set_kern_flags)
633 {
634 const struct cred *cred = current_cred();
635 struct superblock_security_struct *sbsec = selinux_superblock(sb);
636 struct dentry *root = sb->s_root;
637 struct selinux_mnt_opts *opts = mnt_opts;
638 struct inode_security_struct *root_isec;
639 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
640 u32 defcontext_sid = 0;
641 int rc = 0;
642
643 mutex_lock(&sbsec->lock);
644
645 if (!selinux_initialized(&selinux_state)) {
646 if (!opts) {
647 /* Defer initialization until selinux_complete_init,
648 after the initial policy is loaded and the security
649 server is ready to handle calls. */
650 goto out;
651 }
652 rc = -EINVAL;
653 pr_warn("SELinux: Unable to set superblock options "
654 "before the security server is initialized\n");
655 goto out;
656 }
657 if (kern_flags && !set_kern_flags) {
658 /* Specifying internal flags without providing a place to
659 * place the results is not allowed */
660 rc = -EINVAL;
661 goto out;
662 }
663
664 /*
665 * Binary mount data FS will come through this function twice. Once
666 * from an explicit call and once from the generic calls from the vfs.
667 * Since the generic VFS calls will not contain any security mount data
668 * we need to skip the double mount verification.
669 *
670 * This does open a hole in which we will not notice if the first
671 * mount using this sb set explict options and a second mount using
672 * this sb does not set any security options. (The first options
673 * will be used for both mounts)
674 */
675 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
676 && !opts)
677 goto out;
678
679 root_isec = backing_inode_security_novalidate(root);
680
681 /*
682 * parse the mount options, check if they are valid sids.
683 * also check if someone is trying to mount the same sb more
684 * than once with different security options.
685 */
686 if (opts) {
687 if (opts->fscontext) {
688 rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
689 if (rc)
690 goto out;
691 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
692 fscontext_sid))
693 goto out_double_mount;
694 sbsec->flags |= FSCONTEXT_MNT;
695 }
696 if (opts->context) {
697 rc = parse_sid(sb, opts->context, &context_sid);
698 if (rc)
699 goto out;
700 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
701 context_sid))
702 goto out_double_mount;
703 sbsec->flags |= CONTEXT_MNT;
704 }
705 if (opts->rootcontext) {
706 rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
707 if (rc)
708 goto out;
709 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
710 rootcontext_sid))
711 goto out_double_mount;
712 sbsec->flags |= ROOTCONTEXT_MNT;
713 }
714 if (opts->defcontext) {
715 rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
716 if (rc)
717 goto out;
718 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
719 defcontext_sid))
720 goto out_double_mount;
721 sbsec->flags |= DEFCONTEXT_MNT;
722 }
723 }
724
725 if (sbsec->flags & SE_SBINITIALIZED) {
726 /* previously mounted with options, but not on this attempt? */
727 if ((sbsec->flags & SE_MNTMASK) && !opts)
728 goto out_double_mount;
729 rc = 0;
730 goto out;
731 }
732
733 if (strcmp(sb->s_type->name, "proc") == 0)
734 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
735
736 if (!strcmp(sb->s_type->name, "debugfs") ||
737 !strcmp(sb->s_type->name, "tracefs") ||
738 !strcmp(sb->s_type->name, "binder") ||
739 !strcmp(sb->s_type->name, "bpf") ||
740 !strcmp(sb->s_type->name, "pstore"))
741 sbsec->flags |= SE_SBGENFS;
742
743 if (!strcmp(sb->s_type->name, "sysfs") ||
744 !strcmp(sb->s_type->name, "cgroup") ||
745 !strcmp(sb->s_type->name, "cgroup2"))
746 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
747
748 if (!sbsec->behavior) {
749 /*
750 * Determine the labeling behavior to use for this
751 * filesystem type.
752 */
753 rc = security_fs_use(&selinux_state, sb);
754 if (rc) {
755 pr_warn("%s: security_fs_use(%s) returned %d\n",
756 __func__, sb->s_type->name, rc);
757 goto out;
758 }
759 }
760
761 /*
762 * If this is a user namespace mount and the filesystem type is not
763 * explicitly whitelisted, then no contexts are allowed on the command
764 * line and security labels must be ignored.
765 */
766 if (sb->s_user_ns != &init_user_ns &&
767 strcmp(sb->s_type->name, "tmpfs") &&
768 strcmp(sb->s_type->name, "ramfs") &&
769 strcmp(sb->s_type->name, "devpts") &&
770 strcmp(sb->s_type->name, "overlay")) {
771 if (context_sid || fscontext_sid || rootcontext_sid ||
772 defcontext_sid) {
773 rc = -EACCES;
774 goto out;
775 }
776 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
777 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
778 rc = security_transition_sid(&selinux_state,
779 current_sid(),
780 current_sid(),
781 SECCLASS_FILE, NULL,
782 &sbsec->mntpoint_sid);
783 if (rc)
784 goto out;
785 }
786 goto out_set_opts;
787 }
788
789 /* sets the context of the superblock for the fs being mounted. */
790 if (fscontext_sid) {
791 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
792 if (rc)
793 goto out;
794
795 sbsec->sid = fscontext_sid;
796 }
797
798 /*
799 * Switch to using mount point labeling behavior.
800 * sets the label used on all file below the mountpoint, and will set
801 * the superblock context if not already set.
802 */
803 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
804 sbsec->behavior = SECURITY_FS_USE_NATIVE;
805 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
806 }
807
808 if (context_sid) {
809 if (!fscontext_sid) {
810 rc = may_context_mount_sb_relabel(context_sid, sbsec,
811 cred);
812 if (rc)
813 goto out;
814 sbsec->sid = context_sid;
815 } else {
816 rc = may_context_mount_inode_relabel(context_sid, sbsec,
817 cred);
818 if (rc)
819 goto out;
820 }
821 if (!rootcontext_sid)
822 rootcontext_sid = context_sid;
823
824 sbsec->mntpoint_sid = context_sid;
825 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
826 }
827
828 if (rootcontext_sid) {
829 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
830 cred);
831 if (rc)
832 goto out;
833
834 root_isec->sid = rootcontext_sid;
835 root_isec->initialized = LABEL_INITIALIZED;
836 }
837
838 if (defcontext_sid) {
839 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
840 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
841 rc = -EINVAL;
842 pr_warn("SELinux: defcontext option is "
843 "invalid for this filesystem type\n");
844 goto out;
845 }
846
847 if (defcontext_sid != sbsec->def_sid) {
848 rc = may_context_mount_inode_relabel(defcontext_sid,
849 sbsec, cred);
850 if (rc)
851 goto out;
852 }
853
854 sbsec->def_sid = defcontext_sid;
855 }
856
857 out_set_opts:
858 rc = sb_finish_set_opts(sb);
859 out:
860 mutex_unlock(&sbsec->lock);
861 return rc;
862 out_double_mount:
863 rc = -EINVAL;
864 pr_warn("SELinux: mount invalid. Same superblock, different "
865 "security settings for (dev %s, type %s)\n", sb->s_id,
866 sb->s_type->name);
867 goto out;
868 }
869
870 static int selinux_cmp_sb_context(const struct super_block *oldsb,
871 const struct super_block *newsb)
872 {
873 struct superblock_security_struct *old = selinux_superblock(oldsb);
874 struct superblock_security_struct *new = selinux_superblock(newsb);
875 char oldflags = old->flags & SE_MNTMASK;
876 char newflags = new->flags & SE_MNTMASK;
877
878 if (oldflags != newflags)
879 goto mismatch;
880 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
881 goto mismatch;
882 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
883 goto mismatch;
884 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
885 goto mismatch;
886 if (oldflags & ROOTCONTEXT_MNT) {
887 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
888 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
889 if (oldroot->sid != newroot->sid)
890 goto mismatch;
891 }
892 return 0;
893 mismatch:
894 pr_warn("SELinux: mount invalid. Same superblock, "
895 "different security settings for (dev %s, "
896 "type %s)\n", newsb->s_id, newsb->s_type->name);
897 return -EBUSY;
898 }
899
900 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
901 struct super_block *newsb,
902 unsigned long kern_flags,
903 unsigned long *set_kern_flags)
904 {
905 int rc = 0;
906 const struct superblock_security_struct *oldsbsec =
907 selinux_superblock(oldsb);
908 struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
909
910 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
911 int set_context = (oldsbsec->flags & CONTEXT_MNT);
912 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
913
914 /*
915 * if the parent was able to be mounted it clearly had no special lsm
916 * mount options. thus we can safely deal with this superblock later
917 */
918 if (!selinux_initialized(&selinux_state))
919 return 0;
920
921 /*
922 * Specifying internal flags without providing a place to
923 * place the results is not allowed.
924 */
925 if (kern_flags && !set_kern_flags)
926 return -EINVAL;
927
928 /* how can we clone if the old one wasn't set up?? */
929 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
930
931 /* if fs is reusing a sb, make sure that the contexts match */
932 if (newsbsec->flags & SE_SBINITIALIZED) {
933 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
934 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
935 return selinux_cmp_sb_context(oldsb, newsb);
936 }
937
938 mutex_lock(&newsbsec->lock);
939
940 newsbsec->flags = oldsbsec->flags;
941
942 newsbsec->sid = oldsbsec->sid;
943 newsbsec->def_sid = oldsbsec->def_sid;
944 newsbsec->behavior = oldsbsec->behavior;
945
946 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
947 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
948 rc = security_fs_use(&selinux_state, newsb);
949 if (rc)
950 goto out;
951 }
952
953 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
954 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
955 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
956 }
957
958 if (set_context) {
959 u32 sid = oldsbsec->mntpoint_sid;
960
961 if (!set_fscontext)
962 newsbsec->sid = sid;
963 if (!set_rootcontext) {
964 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
965 newisec->sid = sid;
966 }
967 newsbsec->mntpoint_sid = sid;
968 }
969 if (set_rootcontext) {
970 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
971 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
972
973 newisec->sid = oldisec->sid;
974 }
975
976 sb_finish_set_opts(newsb);
977 out:
978 mutex_unlock(&newsbsec->lock);
979 return rc;
980 }
981
982 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
983 {
984 struct selinux_mnt_opts *opts = *mnt_opts;
985
986 if (token == Opt_seclabel) /* eaten and completely ignored */
987 return 0;
988
989 if (!opts) {
990 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
991 if (!opts)
992 return -ENOMEM;
993 *mnt_opts = opts;
994 }
995 if (!s)
996 return -ENOMEM;
997 switch (token) {
998 case Opt_context:
999 if (opts->context || opts->defcontext)
1000 goto Einval;
1001 opts->context = s;
1002 break;
1003 case Opt_fscontext:
1004 if (opts->fscontext)
1005 goto Einval;
1006 opts->fscontext = s;
1007 break;
1008 case Opt_rootcontext:
1009 if (opts->rootcontext)
1010 goto Einval;
1011 opts->rootcontext = s;
1012 break;
1013 case Opt_defcontext:
1014 if (opts->context || opts->defcontext)
1015 goto Einval;
1016 opts->defcontext = s;
1017 break;
1018 }
1019 return 0;
1020 Einval:
1021 pr_warn(SEL_MOUNT_FAIL_MSG);
1022 return -EINVAL;
1023 }
1024
1025 static int selinux_add_mnt_opt(const char *option, const char *val, int len,
1026 void **mnt_opts)
1027 {
1028 int token = Opt_error;
1029 int rc, i;
1030
1031 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
1032 if (strcmp(option, tokens[i].name) == 0) {
1033 token = tokens[i].opt;
1034 break;
1035 }
1036 }
1037
1038 if (token == Opt_error)
1039 return -EINVAL;
1040
1041 if (token != Opt_seclabel) {
1042 val = kmemdup_nul(val, len, GFP_KERNEL);
1043 if (!val) {
1044 rc = -ENOMEM;
1045 goto free_opt;
1046 }
1047 }
1048 rc = selinux_add_opt(token, val, mnt_opts);
1049 if (unlikely(rc)) {
1050 kfree(val);
1051 goto free_opt;
1052 }
1053 return rc;
1054
1055 free_opt:
1056 if (*mnt_opts) {
1057 selinux_free_mnt_opts(*mnt_opts);
1058 *mnt_opts = NULL;
1059 }
1060 return rc;
1061 }
1062
1063 static int show_sid(struct seq_file *m, u32 sid)
1064 {
1065 char *context = NULL;
1066 u32 len;
1067 int rc;
1068
1069 rc = security_sid_to_context(&selinux_state, sid,
1070 &context, &len);
1071 if (!rc) {
1072 bool has_comma = context && strchr(context, ',');
1073
1074 seq_putc(m, '=');
1075 if (has_comma)
1076 seq_putc(m, '\"');
1077 seq_escape(m, context, "\"\n\\");
1078 if (has_comma)
1079 seq_putc(m, '\"');
1080 }
1081 kfree(context);
1082 return rc;
1083 }
1084
1085 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1086 {
1087 struct superblock_security_struct *sbsec = selinux_superblock(sb);
1088 int rc;
1089
1090 if (!(sbsec->flags & SE_SBINITIALIZED))
1091 return 0;
1092
1093 if (!selinux_initialized(&selinux_state))
1094 return 0;
1095
1096 if (sbsec->flags & FSCONTEXT_MNT) {
1097 seq_putc(m, ',');
1098 seq_puts(m, FSCONTEXT_STR);
1099 rc = show_sid(m, sbsec->sid);
1100 if (rc)
1101 return rc;
1102 }
1103 if (sbsec->flags & CONTEXT_MNT) {
1104 seq_putc(m, ',');
1105 seq_puts(m, CONTEXT_STR);
1106 rc = show_sid(m, sbsec->mntpoint_sid);
1107 if (rc)
1108 return rc;
1109 }
1110 if (sbsec->flags & DEFCONTEXT_MNT) {
1111 seq_putc(m, ',');
1112 seq_puts(m, DEFCONTEXT_STR);
1113 rc = show_sid(m, sbsec->def_sid);
1114 if (rc)
1115 return rc;
1116 }
1117 if (sbsec->flags & ROOTCONTEXT_MNT) {
1118 struct dentry *root = sb->s_root;
1119 struct inode_security_struct *isec = backing_inode_security(root);
1120 seq_putc(m, ',');
1121 seq_puts(m, ROOTCONTEXT_STR);
1122 rc = show_sid(m, isec->sid);
1123 if (rc)
1124 return rc;
1125 }
1126 if (sbsec->flags & SBLABEL_MNT) {
1127 seq_putc(m, ',');
1128 seq_puts(m, SECLABEL_STR);
1129 }
1130 return 0;
1131 }
1132
1133 static inline u16 inode_mode_to_security_class(umode_t mode)
1134 {
1135 switch (mode & S_IFMT) {
1136 case S_IFSOCK:
1137 return SECCLASS_SOCK_FILE;
1138 case S_IFLNK:
1139 return SECCLASS_LNK_FILE;
1140 case S_IFREG:
1141 return SECCLASS_FILE;
1142 case S_IFBLK:
1143 return SECCLASS_BLK_FILE;
1144 case S_IFDIR:
1145 return SECCLASS_DIR;
1146 case S_IFCHR:
1147 return SECCLASS_CHR_FILE;
1148 case S_IFIFO:
1149 return SECCLASS_FIFO_FILE;
1150
1151 }
1152
1153 return SECCLASS_FILE;
1154 }
1155
1156 static inline int default_protocol_stream(int protocol)
1157 {
1158 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1159 protocol == IPPROTO_MPTCP);
1160 }
1161
1162 static inline int default_protocol_dgram(int protocol)
1163 {
1164 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1165 }
1166
1167 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1168 {
1169 int extsockclass = selinux_policycap_extsockclass();
1170
1171 switch (family) {
1172 case PF_UNIX:
1173 switch (type) {
1174 case SOCK_STREAM:
1175 case SOCK_SEQPACKET:
1176 return SECCLASS_UNIX_STREAM_SOCKET;
1177 case SOCK_DGRAM:
1178 case SOCK_RAW:
1179 return SECCLASS_UNIX_DGRAM_SOCKET;
1180 }
1181 break;
1182 case PF_INET:
1183 case PF_INET6:
1184 switch (type) {
1185 case SOCK_STREAM:
1186 case SOCK_SEQPACKET:
1187 if (default_protocol_stream(protocol))
1188 return SECCLASS_TCP_SOCKET;
1189 else if (extsockclass && protocol == IPPROTO_SCTP)
1190 return SECCLASS_SCTP_SOCKET;
1191 else
1192 return SECCLASS_RAWIP_SOCKET;
1193 case SOCK_DGRAM:
1194 if (default_protocol_dgram(protocol))
1195 return SECCLASS_UDP_SOCKET;
1196 else if (extsockclass && (protocol == IPPROTO_ICMP ||
1197 protocol == IPPROTO_ICMPV6))
1198 return SECCLASS_ICMP_SOCKET;
1199 else
1200 return SECCLASS_RAWIP_SOCKET;
1201 case SOCK_DCCP:
1202 return SECCLASS_DCCP_SOCKET;
1203 default:
1204 return SECCLASS_RAWIP_SOCKET;
1205 }
1206 break;
1207 case PF_NETLINK:
1208 switch (protocol) {
1209 case NETLINK_ROUTE:
1210 return SECCLASS_NETLINK_ROUTE_SOCKET;
1211 case NETLINK_SOCK_DIAG:
1212 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1213 case NETLINK_NFLOG:
1214 return SECCLASS_NETLINK_NFLOG_SOCKET;
1215 case NETLINK_XFRM:
1216 return SECCLASS_NETLINK_XFRM_SOCKET;
1217 case NETLINK_SELINUX:
1218 return SECCLASS_NETLINK_SELINUX_SOCKET;
1219 case NETLINK_ISCSI:
1220 return SECCLASS_NETLINK_ISCSI_SOCKET;
1221 case NETLINK_AUDIT:
1222 return SECCLASS_NETLINK_AUDIT_SOCKET;
1223 case NETLINK_FIB_LOOKUP:
1224 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1225 case NETLINK_CONNECTOR:
1226 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1227 case NETLINK_NETFILTER:
1228 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1229 case NETLINK_DNRTMSG:
1230 return SECCLASS_NETLINK_DNRT_SOCKET;
1231 case NETLINK_KOBJECT_UEVENT:
1232 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1233 case NETLINK_GENERIC:
1234 return SECCLASS_NETLINK_GENERIC_SOCKET;
1235 case NETLINK_SCSITRANSPORT:
1236 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1237 case NETLINK_RDMA:
1238 return SECCLASS_NETLINK_RDMA_SOCKET;
1239 case NETLINK_CRYPTO:
1240 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1241 default:
1242 return SECCLASS_NETLINK_SOCKET;
1243 }
1244 case PF_PACKET:
1245 return SECCLASS_PACKET_SOCKET;
1246 case PF_KEY:
1247 return SECCLASS_KEY_SOCKET;
1248 case PF_APPLETALK:
1249 return SECCLASS_APPLETALK_SOCKET;
1250 }
1251
1252 if (extsockclass) {
1253 switch (family) {
1254 case PF_AX25:
1255 return SECCLASS_AX25_SOCKET;
1256 case PF_IPX:
1257 return SECCLASS_IPX_SOCKET;
1258 case PF_NETROM:
1259 return SECCLASS_NETROM_SOCKET;
1260 case PF_ATMPVC:
1261 return SECCLASS_ATMPVC_SOCKET;
1262 case PF_X25:
1263 return SECCLASS_X25_SOCKET;
1264 case PF_ROSE:
1265 return SECCLASS_ROSE_SOCKET;
1266 case PF_DECnet:
1267 return SECCLASS_DECNET_SOCKET;
1268 case PF_ATMSVC:
1269 return SECCLASS_ATMSVC_SOCKET;
1270 case PF_RDS:
1271 return SECCLASS_RDS_SOCKET;
1272 case PF_IRDA:
1273 return SECCLASS_IRDA_SOCKET;
1274 case PF_PPPOX:
1275 return SECCLASS_PPPOX_SOCKET;
1276 case PF_LLC:
1277 return SECCLASS_LLC_SOCKET;
1278 case PF_CAN:
1279 return SECCLASS_CAN_SOCKET;
1280 case PF_TIPC:
1281 return SECCLASS_TIPC_SOCKET;
1282 case PF_BLUETOOTH:
1283 return SECCLASS_BLUETOOTH_SOCKET;
1284 case PF_IUCV:
1285 return SECCLASS_IUCV_SOCKET;
1286 case PF_RXRPC:
1287 return SECCLASS_RXRPC_SOCKET;
1288 case PF_ISDN:
1289 return SECCLASS_ISDN_SOCKET;
1290 case PF_PHONET:
1291 return SECCLASS_PHONET_SOCKET;
1292 case PF_IEEE802154:
1293 return SECCLASS_IEEE802154_SOCKET;
1294 case PF_CAIF:
1295 return SECCLASS_CAIF_SOCKET;
1296 case PF_ALG:
1297 return SECCLASS_ALG_SOCKET;
1298 case PF_NFC:
1299 return SECCLASS_NFC_SOCKET;
1300 case PF_VSOCK:
1301 return SECCLASS_VSOCK_SOCKET;
1302 case PF_KCM:
1303 return SECCLASS_KCM_SOCKET;
1304 case PF_QIPCRTR:
1305 return SECCLASS_QIPCRTR_SOCKET;
1306 case PF_SMC:
1307 return SECCLASS_SMC_SOCKET;
1308 case PF_XDP:
1309 return SECCLASS_XDP_SOCKET;
1310 case PF_MCTP:
1311 return SECCLASS_MCTP_SOCKET;
1312 #if PF_MAX > 46
1313 #error New address family defined, please update this function.
1314 #endif
1315 }
1316 }
1317
1318 return SECCLASS_SOCKET;
1319 }
1320
1321 static int selinux_genfs_get_sid(struct dentry *dentry,
1322 u16 tclass,
1323 u16 flags,
1324 u32 *sid)
1325 {
1326 int rc;
1327 struct super_block *sb = dentry->d_sb;
1328 char *buffer, *path;
1329
1330 buffer = (char *)__get_free_page(GFP_KERNEL);
1331 if (!buffer)
1332 return -ENOMEM;
1333
1334 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1335 if (IS_ERR(path))
1336 rc = PTR_ERR(path);
1337 else {
1338 if (flags & SE_SBPROC) {
1339 /* each process gets a /proc/PID/ entry. Strip off the
1340 * PID part to get a valid selinux labeling.
1341 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1342 while (path[1] >= '0' && path[1] <= '9') {
1343 path[1] = '/';
1344 path++;
1345 }
1346 }
1347 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1348 path, tclass, sid);
1349 if (rc == -ENOENT) {
1350 /* No match in policy, mark as unlabeled. */
1351 *sid = SECINITSID_UNLABELED;
1352 rc = 0;
1353 }
1354 }
1355 free_page((unsigned long)buffer);
1356 return rc;
1357 }
1358
1359 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1360 u32 def_sid, u32 *sid)
1361 {
1362 #define INITCONTEXTLEN 255
1363 char *context;
1364 unsigned int len;
1365 int rc;
1366
1367 len = INITCONTEXTLEN;
1368 context = kmalloc(len + 1, GFP_NOFS);
1369 if (!context)
1370 return -ENOMEM;
1371
1372 context[len] = '\0';
1373 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1374 if (rc == -ERANGE) {
1375 kfree(context);
1376
1377 /* Need a larger buffer. Query for the right size. */
1378 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1379 if (rc < 0)
1380 return rc;
1381
1382 len = rc;
1383 context = kmalloc(len + 1, GFP_NOFS);
1384 if (!context)
1385 return -ENOMEM;
1386
1387 context[len] = '\0';
1388 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1389 context, len);
1390 }
1391 if (rc < 0) {
1392 kfree(context);
1393 if (rc != -ENODATA) {
1394 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n",
1395 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1396 return rc;
1397 }
1398 *sid = def_sid;
1399 return 0;
1400 }
1401
1402 rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
1403 def_sid, GFP_NOFS);
1404 if (rc) {
1405 char *dev = inode->i_sb->s_id;
1406 unsigned long ino = inode->i_ino;
1407
1408 if (rc == -EINVAL) {
1409 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",
1410 ino, dev, context);
1411 } else {
1412 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1413 __func__, context, -rc, dev, ino);
1414 }
1415 }
1416 kfree(context);
1417 return 0;
1418 }
1419
1420 /* The inode's security attributes must be initialized before first use. */
1421 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1422 {
1423 struct superblock_security_struct *sbsec = NULL;
1424 struct inode_security_struct *isec = selinux_inode(inode);
1425 u32 task_sid, sid = 0;
1426 u16 sclass;
1427 struct dentry *dentry;
1428 int rc = 0;
1429
1430 if (isec->initialized == LABEL_INITIALIZED)
1431 return 0;
1432
1433 spin_lock(&isec->lock);
1434 if (isec->initialized == LABEL_INITIALIZED)
1435 goto out_unlock;
1436
1437 if (isec->sclass == SECCLASS_FILE)
1438 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1439
1440 sbsec = selinux_superblock(inode->i_sb);
1441 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1442 /* Defer initialization until selinux_complete_init,
1443 after the initial policy is loaded and the security
1444 server is ready to handle calls. */
1445 spin_lock(&sbsec->isec_lock);
1446 if (list_empty(&isec->list))
1447 list_add(&isec->list, &sbsec->isec_head);
1448 spin_unlock(&sbsec->isec_lock);
1449 goto out_unlock;
1450 }
1451
1452 sclass = isec->sclass;
1453 task_sid = isec->task_sid;
1454 sid = isec->sid;
1455 isec->initialized = LABEL_PENDING;
1456 spin_unlock(&isec->lock);
1457
1458 switch (sbsec->behavior) {
1459 case SECURITY_FS_USE_NATIVE:
1460 break;
1461 case SECURITY_FS_USE_XATTR:
1462 if (!(inode->i_opflags & IOP_XATTR)) {
1463 sid = sbsec->def_sid;
1464 break;
1465 }
1466 /* Need a dentry, since the xattr API requires one.
1467 Life would be simpler if we could just pass the inode. */
1468 if (opt_dentry) {
1469 /* Called from d_instantiate or d_splice_alias. */
1470 dentry = dget(opt_dentry);
1471 } else {
1472 /*
1473 * Called from selinux_complete_init, try to find a dentry.
1474 * Some filesystems really want a connected one, so try
1475 * that first. We could split SECURITY_FS_USE_XATTR in
1476 * two, depending upon that...
1477 */
1478 dentry = d_find_alias(inode);
1479 if (!dentry)
1480 dentry = d_find_any_alias(inode);
1481 }
1482 if (!dentry) {
1483 /*
1484 * this is can be hit on boot when a file is accessed
1485 * before the policy is loaded. When we load policy we
1486 * may find inodes that have no dentry on the
1487 * sbsec->isec_head list. No reason to complain as these
1488 * will get fixed up the next time we go through
1489 * inode_doinit with a dentry, before these inodes could
1490 * be used again by userspace.
1491 */
1492 goto out_invalid;
1493 }
1494
1495 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1496 &sid);
1497 dput(dentry);
1498 if (rc)
1499 goto out;
1500 break;
1501 case SECURITY_FS_USE_TASK:
1502 sid = task_sid;
1503 break;
1504 case SECURITY_FS_USE_TRANS:
1505 /* Default to the fs SID. */
1506 sid = sbsec->sid;
1507
1508 /* Try to obtain a transition SID. */
1509 rc = security_transition_sid(&selinux_state, task_sid, sid,
1510 sclass, NULL, &sid);
1511 if (rc)
1512 goto out;
1513 break;
1514 case SECURITY_FS_USE_MNTPOINT:
1515 sid = sbsec->mntpoint_sid;
1516 break;
1517 default:
1518 /* Default to the fs superblock SID. */
1519 sid = sbsec->sid;
1520
1521 if ((sbsec->flags & SE_SBGENFS) &&
1522 (!S_ISLNK(inode->i_mode) ||
1523 selinux_policycap_genfs_seclabel_symlinks())) {
1524 /* We must have a dentry to determine the label on
1525 * procfs inodes */
1526 if (opt_dentry) {
1527 /* Called from d_instantiate or
1528 * d_splice_alias. */
1529 dentry = dget(opt_dentry);
1530 } else {
1531 /* Called from selinux_complete_init, try to
1532 * find a dentry. Some filesystems really want
1533 * a connected one, so try that first.
1534 */
1535 dentry = d_find_alias(inode);
1536 if (!dentry)
1537 dentry = d_find_any_alias(inode);
1538 }
1539 /*
1540 * This can be hit on boot when a file is accessed
1541 * before the policy is loaded. When we load policy we
1542 * may find inodes that have no dentry on the
1543 * sbsec->isec_head list. No reason to complain as
1544 * these will get fixed up the next time we go through
1545 * inode_doinit() with a dentry, before these inodes
1546 * could be used again by userspace.
1547 */
1548 if (!dentry)
1549 goto out_invalid;
1550 rc = selinux_genfs_get_sid(dentry, sclass,
1551 sbsec->flags, &sid);
1552 if (rc) {
1553 dput(dentry);
1554 goto out;
1555 }
1556
1557 if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1558 (inode->i_opflags & IOP_XATTR)) {
1559 rc = inode_doinit_use_xattr(inode, dentry,
1560 sid, &sid);
1561 if (rc) {
1562 dput(dentry);
1563 goto out;
1564 }
1565 }
1566 dput(dentry);
1567 }
1568 break;
1569 }
1570
1571 out:
1572 spin_lock(&isec->lock);
1573 if (isec->initialized == LABEL_PENDING) {
1574 if (rc) {
1575 isec->initialized = LABEL_INVALID;
1576 goto out_unlock;
1577 }
1578 isec->initialized = LABEL_INITIALIZED;
1579 isec->sid = sid;
1580 }
1581
1582 out_unlock:
1583 spin_unlock(&isec->lock);
1584 return rc;
1585
1586 out_invalid:
1587 spin_lock(&isec->lock);
1588 if (isec->initialized == LABEL_PENDING) {
1589 isec->initialized = LABEL_INVALID;
1590 isec->sid = sid;
1591 }
1592 spin_unlock(&isec->lock);
1593 return 0;
1594 }
1595
1596 /* Convert a Linux signal to an access vector. */
1597 static 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. */
1628 static 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);
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). */
1668 static 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. */
1691 static 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. */
1707 static 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. */
1721 static 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
1733 static 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. */
1744 static 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
1778 out:
1779 return rc;
1780 }
1781
1782 /*
1783 * Determine the label for an inode that might be unioned.
1784 */
1785 static int
1786 selinux_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 =
1792 selinux_superblock(dir->i_sb);
1793
1794 if ((sbsec->flags & SE_SBINITIALIZED) &&
1795 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1796 *_new_isid = sbsec->mntpoint_sid;
1797 } else if ((sbsec->flags & SBLABEL_MNT) &&
1798 tsec->create_sid) {
1799 *_new_isid = tsec->create_sid;
1800 } else {
1801 const struct inode_security_struct *dsec = inode_security(dir);
1802 return security_transition_sid(&selinux_state, tsec->sid,
1803 dsec->sid, tclass,
1804 name, _new_isid);
1805 }
1806
1807 return 0;
1808 }
1809
1810 /* Check whether a task can create a file. */
1811 static int may_create(struct inode *dir,
1812 struct dentry *dentry,
1813 u16 tclass)
1814 {
1815 const struct task_security_struct *tsec = selinux_cred(current_cred());
1816 struct inode_security_struct *dsec;
1817 struct superblock_security_struct *sbsec;
1818 u32 sid, newsid;
1819 struct common_audit_data ad;
1820 int rc;
1821
1822 dsec = inode_security(dir);
1823 sbsec = selinux_superblock(dir->i_sb);
1824
1825 sid = tsec->sid;
1826
1827 ad.type = LSM_AUDIT_DATA_DENTRY;
1828 ad.u.dentry = dentry;
1829
1830 rc = avc_has_perm(&selinux_state,
1831 sid, dsec->sid, SECCLASS_DIR,
1832 DIR__ADD_NAME | DIR__SEARCH,
1833 &ad);
1834 if (rc)
1835 return rc;
1836
1837 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1838 &newsid);
1839 if (rc)
1840 return rc;
1841
1842 rc = avc_has_perm(&selinux_state,
1843 sid, newsid, tclass, FILE__CREATE, &ad);
1844 if (rc)
1845 return rc;
1846
1847 return avc_has_perm(&selinux_state,
1848 newsid, sbsec->sid,
1849 SECCLASS_FILESYSTEM,
1850 FILESYSTEM__ASSOCIATE, &ad);
1851 }
1852
1853 #define MAY_LINK 0
1854 #define MAY_UNLINK 1
1855 #define MAY_RMDIR 2
1856
1857 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1858 static int may_link(struct inode *dir,
1859 struct dentry *dentry,
1860 int kind)
1861
1862 {
1863 struct inode_security_struct *dsec, *isec;
1864 struct common_audit_data ad;
1865 u32 sid = current_sid();
1866 u32 av;
1867 int rc;
1868
1869 dsec = inode_security(dir);
1870 isec = backing_inode_security(dentry);
1871
1872 ad.type = LSM_AUDIT_DATA_DENTRY;
1873 ad.u.dentry = dentry;
1874
1875 av = DIR__SEARCH;
1876 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1877 rc = avc_has_perm(&selinux_state,
1878 sid, dsec->sid, SECCLASS_DIR, av, &ad);
1879 if (rc)
1880 return rc;
1881
1882 switch (kind) {
1883 case MAY_LINK:
1884 av = FILE__LINK;
1885 break;
1886 case MAY_UNLINK:
1887 av = FILE__UNLINK;
1888 break;
1889 case MAY_RMDIR:
1890 av = DIR__RMDIR;
1891 break;
1892 default:
1893 pr_warn("SELinux: %s: unrecognized kind %d\n",
1894 __func__, kind);
1895 return 0;
1896 }
1897
1898 rc = avc_has_perm(&selinux_state,
1899 sid, isec->sid, isec->sclass, av, &ad);
1900 return rc;
1901 }
1902
1903 static inline int may_rename(struct inode *old_dir,
1904 struct dentry *old_dentry,
1905 struct inode *new_dir,
1906 struct dentry *new_dentry)
1907 {
1908 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1909 struct common_audit_data ad;
1910 u32 sid = current_sid();
1911 u32 av;
1912 int old_is_dir, new_is_dir;
1913 int rc;
1914
1915 old_dsec = inode_security(old_dir);
1916 old_isec = backing_inode_security(old_dentry);
1917 old_is_dir = d_is_dir(old_dentry);
1918 new_dsec = inode_security(new_dir);
1919
1920 ad.type = LSM_AUDIT_DATA_DENTRY;
1921
1922 ad.u.dentry = old_dentry;
1923 rc = avc_has_perm(&selinux_state,
1924 sid, old_dsec->sid, SECCLASS_DIR,
1925 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1926 if (rc)
1927 return rc;
1928 rc = avc_has_perm(&selinux_state,
1929 sid, old_isec->sid,
1930 old_isec->sclass, FILE__RENAME, &ad);
1931 if (rc)
1932 return rc;
1933 if (old_is_dir && new_dir != old_dir) {
1934 rc = avc_has_perm(&selinux_state,
1935 sid, old_isec->sid,
1936 old_isec->sclass, DIR__REPARENT, &ad);
1937 if (rc)
1938 return rc;
1939 }
1940
1941 ad.u.dentry = new_dentry;
1942 av = DIR__ADD_NAME | DIR__SEARCH;
1943 if (d_is_positive(new_dentry))
1944 av |= DIR__REMOVE_NAME;
1945 rc = avc_has_perm(&selinux_state,
1946 sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1947 if (rc)
1948 return rc;
1949 if (d_is_positive(new_dentry)) {
1950 new_isec = backing_inode_security(new_dentry);
1951 new_is_dir = d_is_dir(new_dentry);
1952 rc = avc_has_perm(&selinux_state,
1953 sid, new_isec->sid,
1954 new_isec->sclass,
1955 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1956 if (rc)
1957 return rc;
1958 }
1959
1960 return 0;
1961 }
1962
1963 /* Check whether a task can perform a filesystem operation. */
1964 static int superblock_has_perm(const struct cred *cred,
1965 struct super_block *sb,
1966 u32 perms,
1967 struct common_audit_data *ad)
1968 {
1969 struct superblock_security_struct *sbsec;
1970 u32 sid = cred_sid(cred);
1971
1972 sbsec = selinux_superblock(sb);
1973 return avc_has_perm(&selinux_state,
1974 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1975 }
1976
1977 /* Convert a Linux mode and permission mask to an access vector. */
1978 static inline u32 file_mask_to_av(int mode, int mask)
1979 {
1980 u32 av = 0;
1981
1982 if (!S_ISDIR(mode)) {
1983 if (mask & MAY_EXEC)
1984 av |= FILE__EXECUTE;
1985 if (mask & MAY_READ)
1986 av |= FILE__READ;
1987
1988 if (mask & MAY_APPEND)
1989 av |= FILE__APPEND;
1990 else if (mask & MAY_WRITE)
1991 av |= FILE__WRITE;
1992
1993 } else {
1994 if (mask & MAY_EXEC)
1995 av |= DIR__SEARCH;
1996 if (mask & MAY_WRITE)
1997 av |= DIR__WRITE;
1998 if (mask & MAY_READ)
1999 av |= DIR__READ;
2000 }
2001
2002 return av;
2003 }
2004
2005 /* Convert a Linux file to an access vector. */
2006 static inline u32 file_to_av(struct file *file)
2007 {
2008 u32 av = 0;
2009
2010 if (file->f_mode & FMODE_READ)
2011 av |= FILE__READ;
2012 if (file->f_mode & FMODE_WRITE) {
2013 if (file->f_flags & O_APPEND)
2014 av |= FILE__APPEND;
2015 else
2016 av |= FILE__WRITE;
2017 }
2018 if (!av) {
2019 /*
2020 * Special file opened with flags 3 for ioctl-only use.
2021 */
2022 av = FILE__IOCTL;
2023 }
2024
2025 return av;
2026 }
2027
2028 /*
2029 * Convert a file to an access vector and include the correct
2030 * open permission.
2031 */
2032 static inline u32 open_file_to_av(struct file *file)
2033 {
2034 u32 av = file_to_av(file);
2035 struct inode *inode = file_inode(file);
2036
2037 if (selinux_policycap_openperm() &&
2038 inode->i_sb->s_magic != SOCKFS_MAGIC)
2039 av |= FILE__OPEN;
2040
2041 return av;
2042 }
2043
2044 /* Hook functions begin here. */
2045
2046 static int selinux_binder_set_context_mgr(const struct cred *mgr)
2047 {
2048 return avc_has_perm(&selinux_state,
2049 current_sid(), cred_sid(mgr), SECCLASS_BINDER,
2050 BINDER__SET_CONTEXT_MGR, NULL);
2051 }
2052
2053 static int selinux_binder_transaction(const struct cred *from,
2054 const struct cred *to)
2055 {
2056 u32 mysid = current_sid();
2057 u32 fromsid = cred_sid(from);
2058 u32 tosid = cred_sid(to);
2059 int rc;
2060
2061 if (mysid != fromsid) {
2062 rc = avc_has_perm(&selinux_state,
2063 mysid, fromsid, SECCLASS_BINDER,
2064 BINDER__IMPERSONATE, NULL);
2065 if (rc)
2066 return rc;
2067 }
2068
2069 return avc_has_perm(&selinux_state, fromsid, tosid,
2070 SECCLASS_BINDER, BINDER__CALL, NULL);
2071 }
2072
2073 static int selinux_binder_transfer_binder(const struct cred *from,
2074 const struct cred *to)
2075 {
2076 return avc_has_perm(&selinux_state,
2077 cred_sid(from), cred_sid(to),
2078 SECCLASS_BINDER, BINDER__TRANSFER,
2079 NULL);
2080 }
2081
2082 static int selinux_binder_transfer_file(const struct cred *from,
2083 const struct cred *to,
2084 struct file *file)
2085 {
2086 u32 sid = cred_sid(to);
2087 struct file_security_struct *fsec = selinux_file(file);
2088 struct dentry *dentry = file->f_path.dentry;
2089 struct inode_security_struct *isec;
2090 struct common_audit_data ad;
2091 int rc;
2092
2093 ad.type = LSM_AUDIT_DATA_PATH;
2094 ad.u.path = file->f_path;
2095
2096 if (sid != fsec->sid) {
2097 rc = avc_has_perm(&selinux_state,
2098 sid, fsec->sid,
2099 SECCLASS_FD,
2100 FD__USE,
2101 &ad);
2102 if (rc)
2103 return rc;
2104 }
2105
2106 #ifdef CONFIG_BPF_SYSCALL
2107 rc = bpf_fd_pass(file, sid);
2108 if (rc)
2109 return rc;
2110 #endif
2111
2112 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2113 return 0;
2114
2115 isec = backing_inode_security(dentry);
2116 return avc_has_perm(&selinux_state,
2117 sid, isec->sid, isec->sclass, file_to_av(file),
2118 &ad);
2119 }
2120
2121 static int selinux_ptrace_access_check(struct task_struct *child,
2122 unsigned int mode)
2123 {
2124 u32 sid = current_sid();
2125 u32 csid = task_sid_obj(child);
2126
2127 if (mode & PTRACE_MODE_READ)
2128 return avc_has_perm(&selinux_state,
2129 sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2130
2131 return avc_has_perm(&selinux_state,
2132 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2133 }
2134
2135 static int selinux_ptrace_traceme(struct task_struct *parent)
2136 {
2137 return avc_has_perm(&selinux_state,
2138 task_sid_obj(parent), task_sid_obj(current),
2139 SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2140 }
2141
2142 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2143 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2144 {
2145 return avc_has_perm(&selinux_state,
2146 current_sid(), task_sid_obj(target), SECCLASS_PROCESS,
2147 PROCESS__GETCAP, NULL);
2148 }
2149
2150 static int selinux_capset(struct cred *new, const struct cred *old,
2151 const kernel_cap_t *effective,
2152 const kernel_cap_t *inheritable,
2153 const kernel_cap_t *permitted)
2154 {
2155 return avc_has_perm(&selinux_state,
2156 cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2157 PROCESS__SETCAP, NULL);
2158 }
2159
2160 /*
2161 * (This comment used to live with the selinux_task_setuid hook,
2162 * which was removed).
2163 *
2164 * Since setuid only affects the current process, and since the SELinux
2165 * controls are not based on the Linux identity attributes, SELinux does not
2166 * need to control this operation. However, SELinux does control the use of
2167 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2168 */
2169
2170 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2171 int cap, unsigned int opts)
2172 {
2173 return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2174 }
2175
2176 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2177 {
2178 const struct cred *cred = current_cred();
2179 int rc = 0;
2180
2181 if (!sb)
2182 return 0;
2183
2184 switch (cmds) {
2185 case Q_SYNC:
2186 case Q_QUOTAON:
2187 case Q_QUOTAOFF:
2188 case Q_SETINFO:
2189 case Q_SETQUOTA:
2190 case Q_XQUOTAOFF:
2191 case Q_XQUOTAON:
2192 case Q_XSETQLIM:
2193 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2194 break;
2195 case Q_GETFMT:
2196 case Q_GETINFO:
2197 case Q_GETQUOTA:
2198 case Q_XGETQUOTA:
2199 case Q_XGETQSTAT:
2200 case Q_XGETQSTATV:
2201 case Q_XGETNEXTQUOTA:
2202 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2203 break;
2204 default:
2205 rc = 0; /* let the kernel handle invalid cmds */
2206 break;
2207 }
2208 return rc;
2209 }
2210
2211 static int selinux_quota_on(struct dentry *dentry)
2212 {
2213 const struct cred *cred = current_cred();
2214
2215 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2216 }
2217
2218 static int selinux_syslog(int type)
2219 {
2220 switch (type) {
2221 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2222 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2223 return avc_has_perm(&selinux_state,
2224 current_sid(), SECINITSID_KERNEL,
2225 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2226 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2227 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2228 /* Set level of messages printed to console */
2229 case SYSLOG_ACTION_CONSOLE_LEVEL:
2230 return avc_has_perm(&selinux_state,
2231 current_sid(), SECINITSID_KERNEL,
2232 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2233 NULL);
2234 }
2235 /* All other syslog types */
2236 return avc_has_perm(&selinux_state,
2237 current_sid(), SECINITSID_KERNEL,
2238 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2239 }
2240
2241 /*
2242 * Check that a process has enough memory to allocate a new virtual
2243 * mapping. 0 means there is enough memory for the allocation to
2244 * succeed and -ENOMEM implies there is not.
2245 *
2246 * Do not audit the selinux permission check, as this is applied to all
2247 * processes that allocate mappings.
2248 */
2249 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2250 {
2251 int rc, cap_sys_admin = 0;
2252
2253 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2254 CAP_OPT_NOAUDIT, true);
2255 if (rc == 0)
2256 cap_sys_admin = 1;
2257
2258 return cap_sys_admin;
2259 }
2260
2261 /* binprm security operations */
2262
2263 static u32 ptrace_parent_sid(void)
2264 {
2265 u32 sid = 0;
2266 struct task_struct *tracer;
2267
2268 rcu_read_lock();
2269 tracer = ptrace_parent(current);
2270 if (tracer)
2271 sid = task_sid_obj(tracer);
2272 rcu_read_unlock();
2273
2274 return sid;
2275 }
2276
2277 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2278 const struct task_security_struct *old_tsec,
2279 const struct task_security_struct *new_tsec)
2280 {
2281 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2282 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2283 int rc;
2284 u32 av;
2285
2286 if (!nnp && !nosuid)
2287 return 0; /* neither NNP nor nosuid */
2288
2289 if (new_tsec->sid == old_tsec->sid)
2290 return 0; /* No change in credentials */
2291
2292 /*
2293 * If the policy enables the nnp_nosuid_transition policy capability,
2294 * then we permit transitions under NNP or nosuid if the
2295 * policy allows the corresponding permission between
2296 * the old and new contexts.
2297 */
2298 if (selinux_policycap_nnp_nosuid_transition()) {
2299 av = 0;
2300 if (nnp)
2301 av |= PROCESS2__NNP_TRANSITION;
2302 if (nosuid)
2303 av |= PROCESS2__NOSUID_TRANSITION;
2304 rc = avc_has_perm(&selinux_state,
2305 old_tsec->sid, new_tsec->sid,
2306 SECCLASS_PROCESS2, av, NULL);
2307 if (!rc)
2308 return 0;
2309 }
2310
2311 /*
2312 * We also permit NNP or nosuid transitions to bounded SIDs,
2313 * i.e. SIDs that are guaranteed to only be allowed a subset
2314 * of the permissions of the current SID.
2315 */
2316 rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2317 new_tsec->sid);
2318 if (!rc)
2319 return 0;
2320
2321 /*
2322 * On failure, preserve the errno values for NNP vs nosuid.
2323 * NNP: Operation not permitted for caller.
2324 * nosuid: Permission denied to file.
2325 */
2326 if (nnp)
2327 return -EPERM;
2328 return -EACCES;
2329 }
2330
2331 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2332 {
2333 const struct task_security_struct *old_tsec;
2334 struct task_security_struct *new_tsec;
2335 struct inode_security_struct *isec;
2336 struct common_audit_data ad;
2337 struct inode *inode = file_inode(bprm->file);
2338 int rc;
2339
2340 /* SELinux context only depends on initial program or script and not
2341 * the script interpreter */
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
2445 static 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. */
2451 static 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 */
2502 static 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 */
2549 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2550 {
2551 const struct task_security_struct *tsec = selinux_cred(current_cred());
2552 u32 osid, sid;
2553 int rc;
2554
2555 osid = tsec->osid;
2556 sid = tsec->sid;
2557
2558 if (sid == osid)
2559 return;
2560
2561 /* Check whether the new SID can inherit signal state from the old SID.
2562 * If not, clear itimers to avoid subsequent signal generation and
2563 * flush and unblock signals.
2564 *
2565 * This must occur _after_ the task SID has been updated so that any
2566 * kill done after the flush will be checked against the new SID.
2567 */
2568 rc = avc_has_perm(&selinux_state,
2569 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2570 if (rc) {
2571 clear_itimer();
2572
2573 spin_lock_irq(&current->sighand->siglock);
2574 if (!fatal_signal_pending(current)) {
2575 flush_sigqueue(&current->pending);
2576 flush_sigqueue(&current->signal->shared_pending);
2577 flush_signal_handlers(current, 1);
2578 sigemptyset(&current->blocked);
2579 recalc_sigpending();
2580 }
2581 spin_unlock_irq(&current->sighand->siglock);
2582 }
2583
2584 /* Wake up the parent if it is waiting so that it can recheck
2585 * wait permission to the new task SID. */
2586 read_lock(&tasklist_lock);
2587 __wake_up_parent(current, current->real_parent);
2588 read_unlock(&tasklist_lock);
2589 }
2590
2591 /* superblock security operations */
2592
2593 static int selinux_sb_alloc_security(struct super_block *sb)
2594 {
2595 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2596
2597 mutex_init(&sbsec->lock);
2598 INIT_LIST_HEAD(&sbsec->isec_head);
2599 spin_lock_init(&sbsec->isec_lock);
2600 sbsec->sid = SECINITSID_UNLABELED;
2601 sbsec->def_sid = SECINITSID_FILE;
2602 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2603
2604 return 0;
2605 }
2606
2607 static 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
2622 static 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
2674 free_opt:
2675 if (*mnt_opts) {
2676 selinux_free_mnt_opts(*mnt_opts);
2677 *mnt_opts = NULL;
2678 }
2679 return rc;
2680 }
2681
2682 static int selinux_sb_mnt_opts_compat(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 /*
2690 * Superblock not initialized (i.e. no options) - reject if any
2691 * options specified, otherwise accept.
2692 */
2693 if (!(sbsec->flags & SE_SBINITIALIZED))
2694 return opts ? 1 : 0;
2695
2696 /*
2697 * Superblock initialized and no options specified - reject if
2698 * superblock has any options set, otherwise accept.
2699 */
2700 if (!opts)
2701 return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2702
2703 if (opts->fscontext) {
2704 rc = parse_sid(sb, opts->fscontext, &sid);
2705 if (rc)
2706 return 1;
2707 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2708 return 1;
2709 }
2710 if (opts->context) {
2711 rc = parse_sid(sb, opts->context, &sid);
2712 if (rc)
2713 return 1;
2714 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2715 return 1;
2716 }
2717 if (opts->rootcontext) {
2718 struct inode_security_struct *root_isec;
2719
2720 root_isec = backing_inode_security(sb->s_root);
2721 rc = parse_sid(sb, opts->rootcontext, &sid);
2722 if (rc)
2723 return 1;
2724 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2725 return 1;
2726 }
2727 if (opts->defcontext) {
2728 rc = parse_sid(sb, opts->defcontext, &sid);
2729 if (rc)
2730 return 1;
2731 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2732 return 1;
2733 }
2734 return 0;
2735 }
2736
2737 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2738 {
2739 struct selinux_mnt_opts *opts = mnt_opts;
2740 struct superblock_security_struct *sbsec = selinux_superblock(sb);
2741 u32 sid;
2742 int rc;
2743
2744 if (!(sbsec->flags & SE_SBINITIALIZED))
2745 return 0;
2746
2747 if (!opts)
2748 return 0;
2749
2750 if (opts->fscontext) {
2751 rc = parse_sid(sb, opts->fscontext, &sid);
2752 if (rc)
2753 return rc;
2754 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2755 goto out_bad_option;
2756 }
2757 if (opts->context) {
2758 rc = parse_sid(sb, opts->context, &sid);
2759 if (rc)
2760 return rc;
2761 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2762 goto out_bad_option;
2763 }
2764 if (opts->rootcontext) {
2765 struct inode_security_struct *root_isec;
2766 root_isec = backing_inode_security(sb->s_root);
2767 rc = parse_sid(sb, opts->rootcontext, &sid);
2768 if (rc)
2769 return rc;
2770 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2771 goto out_bad_option;
2772 }
2773 if (opts->defcontext) {
2774 rc = parse_sid(sb, opts->defcontext, &sid);
2775 if (rc)
2776 return rc;
2777 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2778 goto out_bad_option;
2779 }
2780 return 0;
2781
2782 out_bad_option:
2783 pr_warn("SELinux: unable to change security options "
2784 "during remount (dev %s, type=%s)\n", sb->s_id,
2785 sb->s_type->name);
2786 return -EINVAL;
2787 }
2788
2789 static int selinux_sb_kern_mount(struct super_block *sb)
2790 {
2791 const struct cred *cred = current_cred();
2792 struct common_audit_data ad;
2793
2794 ad.type = LSM_AUDIT_DATA_DENTRY;
2795 ad.u.dentry = sb->s_root;
2796 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2797 }
2798
2799 static int selinux_sb_statfs(struct dentry *dentry)
2800 {
2801 const struct cred *cred = current_cred();
2802 struct common_audit_data ad;
2803
2804 ad.type = LSM_AUDIT_DATA_DENTRY;
2805 ad.u.dentry = dentry->d_sb->s_root;
2806 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2807 }
2808
2809 static int selinux_mount(const char *dev_name,
2810 const struct path *path,
2811 const char *type,
2812 unsigned long flags,
2813 void *data)
2814 {
2815 const struct cred *cred = current_cred();
2816
2817 if (flags & MS_REMOUNT)
2818 return superblock_has_perm(cred, path->dentry->d_sb,
2819 FILESYSTEM__REMOUNT, NULL);
2820 else
2821 return path_has_perm(cred, path, FILE__MOUNTON);
2822 }
2823
2824 static int selinux_move_mount(const struct path *from_path,
2825 const struct path *to_path)
2826 {
2827 const struct cred *cred = current_cred();
2828
2829 return path_has_perm(cred, to_path, FILE__MOUNTON);
2830 }
2831
2832 static int selinux_umount(struct vfsmount *mnt, int flags)
2833 {
2834 const struct cred *cred = current_cred();
2835
2836 return superblock_has_perm(cred, mnt->mnt_sb,
2837 FILESYSTEM__UNMOUNT, NULL);
2838 }
2839
2840 static int selinux_fs_context_dup(struct fs_context *fc,
2841 struct fs_context *src_fc)
2842 {
2843 const struct selinux_mnt_opts *src = src_fc->security;
2844 struct selinux_mnt_opts *opts;
2845
2846 if (!src)
2847 return 0;
2848
2849 fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
2850 if (!fc->security)
2851 return -ENOMEM;
2852
2853 opts = fc->security;
2854
2855 if (src->fscontext) {
2856 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL);
2857 if (!opts->fscontext)
2858 return -ENOMEM;
2859 }
2860 if (src->context) {
2861 opts->context = kstrdup(src->context, GFP_KERNEL);
2862 if (!opts->context)
2863 return -ENOMEM;
2864 }
2865 if (src->rootcontext) {
2866 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL);
2867 if (!opts->rootcontext)
2868 return -ENOMEM;
2869 }
2870 if (src->defcontext) {
2871 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL);
2872 if (!opts->defcontext)
2873 return -ENOMEM;
2874 }
2875 return 0;
2876 }
2877
2878 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2879 fsparam_string(CONTEXT_STR, Opt_context),
2880 fsparam_string(DEFCONTEXT_STR, Opt_defcontext),
2881 fsparam_string(FSCONTEXT_STR, Opt_fscontext),
2882 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2883 fsparam_flag (SECLABEL_STR, Opt_seclabel),
2884 {}
2885 };
2886
2887 static int selinux_fs_context_parse_param(struct fs_context *fc,
2888 struct fs_parameter *param)
2889 {
2890 struct fs_parse_result result;
2891 int opt, rc;
2892
2893 opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2894 if (opt < 0)
2895 return opt;
2896
2897 rc = selinux_add_opt(opt, param->string, &fc->security);
2898 if (!rc) {
2899 param->string = NULL;
2900 rc = 1;
2901 }
2902 return rc;
2903 }
2904
2905 /* inode security operations */
2906
2907 static int selinux_inode_alloc_security(struct inode *inode)
2908 {
2909 struct inode_security_struct *isec = selinux_inode(inode);
2910 u32 sid = current_sid();
2911
2912 spin_lock_init(&isec->lock);
2913 INIT_LIST_HEAD(&isec->list);
2914 isec->inode = inode;
2915 isec->sid = SECINITSID_UNLABELED;
2916 isec->sclass = SECCLASS_FILE;
2917 isec->task_sid = sid;
2918 isec->initialized = LABEL_INVALID;
2919
2920 return 0;
2921 }
2922
2923 static void selinux_inode_free_security(struct inode *inode)
2924 {
2925 inode_free_security(inode);
2926 }
2927
2928 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2929 const struct qstr *name, void **ctx,
2930 u32 *ctxlen)
2931 {
2932 u32 newsid;
2933 int rc;
2934
2935 rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2936 d_inode(dentry->d_parent), name,
2937 inode_mode_to_security_class(mode),
2938 &newsid);
2939 if (rc)
2940 return rc;
2941
2942 return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2943 ctxlen);
2944 }
2945
2946 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2947 struct qstr *name,
2948 const struct cred *old,
2949 struct cred *new)
2950 {
2951 u32 newsid;
2952 int rc;
2953 struct task_security_struct *tsec;
2954
2955 rc = selinux_determine_inode_label(selinux_cred(old),
2956 d_inode(dentry->d_parent), name,
2957 inode_mode_to_security_class(mode),
2958 &newsid);
2959 if (rc)
2960 return rc;
2961
2962 tsec = selinux_cred(new);
2963 tsec->create_sid = newsid;
2964 return 0;
2965 }
2966
2967 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2968 const struct qstr *qstr,
2969 const char **name,
2970 void **value, size_t *len)
2971 {
2972 const struct task_security_struct *tsec = selinux_cred(current_cred());
2973 struct superblock_security_struct *sbsec;
2974 u32 newsid, clen;
2975 int rc;
2976 char *context;
2977
2978 sbsec = selinux_superblock(dir->i_sb);
2979
2980 newsid = tsec->create_sid;
2981
2982 rc = selinux_determine_inode_label(tsec, dir, qstr,
2983 inode_mode_to_security_class(inode->i_mode),
2984 &newsid);
2985 if (rc)
2986 return rc;
2987
2988 /* Possibly defer initialization to selinux_complete_init. */
2989 if (sbsec->flags & SE_SBINITIALIZED) {
2990 struct inode_security_struct *isec = selinux_inode(inode);
2991 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2992 isec->sid = newsid;
2993 isec->initialized = LABEL_INITIALIZED;
2994 }
2995
2996 if (!selinux_initialized(&selinux_state) ||
2997 !(sbsec->flags & SBLABEL_MNT))
2998 return -EOPNOTSUPP;
2999
3000 if (name)
3001 *name = XATTR_SELINUX_SUFFIX;
3002
3003 if (value && len) {
3004 rc = security_sid_to_context_force(&selinux_state, newsid,
3005 &context, &clen);
3006 if (rc)
3007 return rc;
3008 *value = context;
3009 *len = clen;
3010 }
3011
3012 return 0;
3013 }
3014
3015 static int selinux_inode_init_security_anon(struct inode *inode,
3016 const struct qstr *name,
3017 const struct inode *context_inode)
3018 {
3019 const struct task_security_struct *tsec = selinux_cred(current_cred());
3020 struct common_audit_data ad;
3021 struct inode_security_struct *isec;
3022 int rc;
3023
3024 if (unlikely(!selinux_initialized(&selinux_state)))
3025 return 0;
3026
3027 isec = selinux_inode(inode);
3028
3029 /*
3030 * We only get here once per ephemeral inode. The inode has
3031 * been initialized via inode_alloc_security but is otherwise
3032 * untouched.
3033 */
3034
3035 if (context_inode) {
3036 struct inode_security_struct *context_isec =
3037 selinux_inode(context_inode);
3038 if (context_isec->initialized != LABEL_INITIALIZED) {
3039 pr_err("SELinux: context_inode is not initialized");
3040 return -EACCES;
3041 }
3042
3043 isec->sclass = context_isec->sclass;
3044 isec->sid = context_isec->sid;
3045 } else {
3046 isec->sclass = SECCLASS_ANON_INODE;
3047 rc = security_transition_sid(
3048 &selinux_state, tsec->sid, tsec->sid,
3049 isec->sclass, name, &isec->sid);
3050 if (rc)
3051 return rc;
3052 }
3053
3054 isec->initialized = LABEL_INITIALIZED;
3055 /*
3056 * Now that we've initialized security, check whether we're
3057 * allowed to actually create this type of anonymous inode.
3058 */
3059
3060 ad.type = LSM_AUDIT_DATA_INODE;
3061 ad.u.inode = inode;
3062
3063 return avc_has_perm(&selinux_state,
3064 tsec->sid,
3065 isec->sid,
3066 isec->sclass,
3067 FILE__CREATE,
3068 &ad);
3069 }
3070
3071 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3072 {
3073 return may_create(dir, dentry, SECCLASS_FILE);
3074 }
3075
3076 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3077 {
3078 return may_link(dir, old_dentry, MAY_LINK);
3079 }
3080
3081 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3082 {
3083 return may_link(dir, dentry, MAY_UNLINK);
3084 }
3085
3086 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3087 {
3088 return may_create(dir, dentry, SECCLASS_LNK_FILE);
3089 }
3090
3091 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3092 {
3093 return may_create(dir, dentry, SECCLASS_DIR);
3094 }
3095
3096 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3097 {
3098 return may_link(dir, dentry, MAY_RMDIR);
3099 }
3100
3101 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3102 {
3103 return may_create(dir, dentry, inode_mode_to_security_class(mode));
3104 }
3105
3106 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3107 struct inode *new_inode, struct dentry *new_dentry)
3108 {
3109 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3110 }
3111
3112 static int selinux_inode_readlink(struct dentry *dentry)
3113 {
3114 const struct cred *cred = current_cred();
3115
3116 return dentry_has_perm(cred, dentry, FILE__READ);
3117 }
3118
3119 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3120 bool rcu)
3121 {
3122 const struct cred *cred = current_cred();
3123 struct common_audit_data ad;
3124 struct inode_security_struct *isec;
3125 u32 sid;
3126
3127 validate_creds(cred);
3128
3129 ad.type = LSM_AUDIT_DATA_DENTRY;
3130 ad.u.dentry = dentry;
3131 sid = cred_sid(cred);
3132 isec = inode_security_rcu(inode, rcu);
3133 if (IS_ERR(isec))
3134 return PTR_ERR(isec);
3135
3136 return avc_has_perm(&selinux_state,
3137 sid, isec->sid, isec->sclass, FILE__READ, &ad);
3138 }
3139
3140 static noinline int audit_inode_permission(struct inode *inode,
3141 u32 perms, u32 audited, u32 denied,
3142 int result)
3143 {
3144 struct common_audit_data ad;
3145 struct inode_security_struct *isec = selinux_inode(inode);
3146
3147 ad.type = LSM_AUDIT_DATA_INODE;
3148 ad.u.inode = inode;
3149
3150 return slow_avc_audit(&selinux_state,
3151 current_sid(), isec->sid, isec->sclass, perms,
3152 audited, denied, result, &ad);
3153 }
3154
3155 static int selinux_inode_permission(struct inode *inode, int mask)
3156 {
3157 const struct cred *cred = current_cred();
3158 u32 perms;
3159 bool from_access;
3160 bool no_block = mask & MAY_NOT_BLOCK;
3161 struct inode_security_struct *isec;
3162 u32 sid;
3163 struct av_decision avd;
3164 int rc, rc2;
3165 u32 audited, denied;
3166
3167 from_access = mask & MAY_ACCESS;
3168 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3169
3170 /* No permission to check. Existence test. */
3171 if (!mask)
3172 return 0;
3173
3174 validate_creds(cred);
3175
3176 if (unlikely(IS_PRIVATE(inode)))
3177 return 0;
3178
3179 perms = file_mask_to_av(inode->i_mode, mask);
3180
3181 sid = cred_sid(cred);
3182 isec = inode_security_rcu(inode, no_block);
3183 if (IS_ERR(isec))
3184 return PTR_ERR(isec);
3185
3186 rc = avc_has_perm_noaudit(&selinux_state,
3187 sid, isec->sid, isec->sclass, perms, 0,
3188 &avd);
3189 audited = avc_audit_required(perms, &avd, rc,
3190 from_access ? FILE__AUDIT_ACCESS : 0,
3191 &denied);
3192 if (likely(!audited))
3193 return rc;
3194
3195 rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3196 if (rc2)
3197 return rc2;
3198 return rc;
3199 }
3200
3201 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3202 {
3203 const struct cred *cred = current_cred();
3204 struct inode *inode = d_backing_inode(dentry);
3205 unsigned int ia_valid = iattr->ia_valid;
3206 __u32 av = FILE__WRITE;
3207
3208 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3209 if (ia_valid & ATTR_FORCE) {
3210 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3211 ATTR_FORCE);
3212 if (!ia_valid)
3213 return 0;
3214 }
3215
3216 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3217 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3218 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3219
3220 if (selinux_policycap_openperm() &&
3221 inode->i_sb->s_magic != SOCKFS_MAGIC &&
3222 (ia_valid & ATTR_SIZE) &&
3223 !(ia_valid & ATTR_FILE))
3224 av |= FILE__OPEN;
3225
3226 return dentry_has_perm(cred, dentry, av);
3227 }
3228
3229 static int selinux_inode_getattr(const struct path *path)
3230 {
3231 return path_has_perm(current_cred(), path, FILE__GETATTR);
3232 }
3233
3234 static bool has_cap_mac_admin(bool audit)
3235 {
3236 const struct cred *cred = current_cred();
3237 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3238
3239 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3240 return false;
3241 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3242 return false;
3243 return true;
3244 }
3245
3246 static int selinux_inode_setxattr(struct user_namespace *mnt_userns,
3247 struct dentry *dentry, const char *name,
3248 const void *value, size_t size, int flags)
3249 {
3250 struct inode *inode = d_backing_inode(dentry);
3251 struct inode_security_struct *isec;
3252 struct superblock_security_struct *sbsec;
3253 struct common_audit_data ad;
3254 u32 newsid, sid = current_sid();
3255 int rc = 0;
3256
3257 if (strcmp(name, XATTR_NAME_SELINUX)) {
3258 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3259 if (rc)
3260 return rc;
3261
3262 /* Not an attribute we recognize, so just check the
3263 ordinary setattr permission. */
3264 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3265 }
3266
3267 if (!selinux_initialized(&selinux_state))
3268 return (inode_owner_or_capable(mnt_userns, inode) ? 0 : -EPERM);
3269
3270 sbsec = selinux_superblock(inode->i_sb);
3271 if (!(sbsec->flags & SBLABEL_MNT))
3272 return -EOPNOTSUPP;
3273
3274 if (!inode_owner_or_capable(mnt_userns, inode))
3275 return -EPERM;
3276
3277 ad.type = LSM_AUDIT_DATA_DENTRY;
3278 ad.u.dentry = dentry;
3279
3280 isec = backing_inode_security(dentry);
3281 rc = avc_has_perm(&selinux_state,
3282 sid, isec->sid, isec->sclass,
3283 FILE__RELABELFROM, &ad);
3284 if (rc)
3285 return rc;
3286
3287 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3288 GFP_KERNEL);
3289 if (rc == -EINVAL) {
3290 if (!has_cap_mac_admin(true)) {
3291 struct audit_buffer *ab;
3292 size_t audit_size;
3293
3294 /* We strip a nul only if it is at the end, otherwise the
3295 * context contains a nul and we should audit that */
3296 if (value) {
3297 const char *str = value;
3298
3299 if (str[size - 1] == '\0')
3300 audit_size = size - 1;
3301 else
3302 audit_size = size;
3303 } else {
3304 audit_size = 0;
3305 }
3306 ab = audit_log_start(audit_context(),
3307 GFP_ATOMIC, AUDIT_SELINUX_ERR);
3308 if (!ab)
3309 return rc;
3310 audit_log_format(ab, "op=setxattr invalid_context=");
3311 audit_log_n_untrustedstring(ab, value, audit_size);
3312 audit_log_end(ab);
3313
3314 return rc;
3315 }
3316 rc = security_context_to_sid_force(&selinux_state, value,
3317 size, &newsid);
3318 }
3319 if (rc)
3320 return rc;
3321
3322 rc = avc_has_perm(&selinux_state,
3323 sid, newsid, isec->sclass,
3324 FILE__RELABELTO, &ad);
3325 if (rc)
3326 return rc;
3327
3328 rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3329 sid, isec->sclass);
3330 if (rc)
3331 return rc;
3332
3333 return avc_has_perm(&selinux_state,
3334 newsid,
3335 sbsec->sid,
3336 SECCLASS_FILESYSTEM,
3337 FILESYSTEM__ASSOCIATE,
3338 &ad);
3339 }
3340
3341 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3342 const void *value, size_t size,
3343 int flags)
3344 {
3345 struct inode *inode = d_backing_inode(dentry);
3346 struct inode_security_struct *isec;
3347 u32 newsid;
3348 int rc;
3349
3350 if (strcmp(name, XATTR_NAME_SELINUX)) {
3351 /* Not an attribute we recognize, so nothing to do. */
3352 return;
3353 }
3354
3355 if (!selinux_initialized(&selinux_state)) {
3356 /* If we haven't even been initialized, then we can't validate
3357 * against a policy, so leave the label as invalid. It may
3358 * resolve to a valid label on the next revalidation try if
3359 * we've since initialized.
3360 */
3361 return;
3362 }
3363
3364 rc = security_context_to_sid_force(&selinux_state, value, size,
3365 &newsid);
3366 if (rc) {
3367 pr_err("SELinux: unable to map context to SID"
3368 "for (%s, %lu), rc=%d\n",
3369 inode->i_sb->s_id, inode->i_ino, -rc);
3370 return;
3371 }
3372
3373 isec = backing_inode_security(dentry);
3374 spin_lock(&isec->lock);
3375 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3376 isec->sid = newsid;
3377 isec->initialized = LABEL_INITIALIZED;
3378 spin_unlock(&isec->lock);
3379
3380 return;
3381 }
3382
3383 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3384 {
3385 const struct cred *cred = current_cred();
3386
3387 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3388 }
3389
3390 static int selinux_inode_listxattr(struct dentry *dentry)
3391 {
3392 const struct cred *cred = current_cred();
3393
3394 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3395 }
3396
3397 static int selinux_inode_removexattr(struct user_namespace *mnt_userns,
3398 struct dentry *dentry, const char *name)
3399 {
3400 if (strcmp(name, XATTR_NAME_SELINUX)) {
3401 int rc = cap_inode_removexattr(mnt_userns, dentry, name);
3402 if (rc)
3403 return rc;
3404
3405 /* Not an attribute we recognize, so just check the
3406 ordinary setattr permission. */
3407 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3408 }
3409
3410 if (!selinux_initialized(&selinux_state))
3411 return 0;
3412
3413 /* No one is allowed to remove a SELinux security label.
3414 You can change the label, but all data must be labeled. */
3415 return -EACCES;
3416 }
3417
3418 static int selinux_path_notify(const struct path *path, u64 mask,
3419 unsigned int obj_type)
3420 {
3421 int ret;
3422 u32 perm;
3423
3424 struct common_audit_data ad;
3425
3426 ad.type = LSM_AUDIT_DATA_PATH;
3427 ad.u.path = *path;
3428
3429 /*
3430 * Set permission needed based on the type of mark being set.
3431 * Performs an additional check for sb watches.
3432 */
3433 switch (obj_type) {
3434 case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3435 perm = FILE__WATCH_MOUNT;
3436 break;
3437 case FSNOTIFY_OBJ_TYPE_SB:
3438 perm = FILE__WATCH_SB;
3439 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3440 FILESYSTEM__WATCH, &ad);
3441 if (ret)
3442 return ret;
3443 break;
3444 case FSNOTIFY_OBJ_TYPE_INODE:
3445 perm = FILE__WATCH;
3446 break;
3447 default:
3448 return -EINVAL;
3449 }
3450
3451 /* blocking watches require the file:watch_with_perm permission */
3452 if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3453 perm |= FILE__WATCH_WITH_PERM;
3454
3455 /* watches on read-like events need the file:watch_reads permission */
3456 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3457 perm |= FILE__WATCH_READS;
3458
3459 return path_has_perm(current_cred(), path, perm);
3460 }
3461
3462 /*
3463 * Copy the inode security context value to the user.
3464 *
3465 * Permission check is handled by selinux_inode_getxattr hook.
3466 */
3467 static int selinux_inode_getsecurity(struct user_namespace *mnt_userns,
3468 struct inode *inode, const char *name,
3469 void **buffer, bool alloc)
3470 {
3471 u32 size;
3472 int error;
3473 char *context = NULL;
3474 struct inode_security_struct *isec;
3475
3476 /*
3477 * If we're not initialized yet, then we can't validate contexts, so
3478 * just let vfs_getxattr fall back to using the on-disk xattr.
3479 */
3480 if (!selinux_initialized(&selinux_state) ||
3481 strcmp(name, XATTR_SELINUX_SUFFIX))
3482 return -EOPNOTSUPP;
3483
3484 /*
3485 * If the caller has CAP_MAC_ADMIN, then get the raw context
3486 * value even if it is not defined by current policy; otherwise,
3487 * use the in-core value under current policy.
3488 * Use the non-auditing forms of the permission checks since
3489 * getxattr may be called by unprivileged processes commonly
3490 * and lack of permission just means that we fall back to the
3491 * in-core context value, not a denial.
3492 */
3493 isec = inode_security(inode);
3494 if (has_cap_mac_admin(false))
3495 error = security_sid_to_context_force(&selinux_state,
3496 isec->sid, &context,
3497 &size);
3498 else
3499 error = security_sid_to_context(&selinux_state, isec->sid,
3500 &context, &size);
3501 if (error)
3502 return error;
3503 error = size;
3504 if (alloc) {
3505 *buffer = context;
3506 goto out_nofree;
3507 }
3508 kfree(context);
3509 out_nofree:
3510 return error;
3511 }
3512
3513 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3514 const void *value, size_t size, int flags)
3515 {
3516 struct inode_security_struct *isec = inode_security_novalidate(inode);
3517 struct superblock_security_struct *sbsec;
3518 u32 newsid;
3519 int rc;
3520
3521 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3522 return -EOPNOTSUPP;
3523
3524 sbsec = selinux_superblock(inode->i_sb);
3525 if (!(sbsec->flags & SBLABEL_MNT))
3526 return -EOPNOTSUPP;
3527
3528 if (!value || !size)
3529 return -EACCES;
3530
3531 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3532 GFP_KERNEL);
3533 if (rc)
3534 return rc;
3535
3536 spin_lock(&isec->lock);
3537 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3538 isec->sid = newsid;
3539 isec->initialized = LABEL_INITIALIZED;
3540 spin_unlock(&isec->lock);
3541 return 0;
3542 }
3543
3544 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3545 {
3546 const int len = sizeof(XATTR_NAME_SELINUX);
3547
3548 if (!selinux_initialized(&selinux_state))
3549 return 0;
3550
3551 if (buffer && len <= buffer_size)
3552 memcpy(buffer, XATTR_NAME_SELINUX, len);
3553 return len;
3554 }
3555
3556 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3557 {
3558 struct inode_security_struct *isec = inode_security_novalidate(inode);
3559 *secid = isec->sid;
3560 }
3561
3562 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3563 {
3564 u32 sid;
3565 struct task_security_struct *tsec;
3566 struct cred *new_creds = *new;
3567
3568 if (new_creds == NULL) {
3569 new_creds = prepare_creds();
3570 if (!new_creds)
3571 return -ENOMEM;
3572 }
3573
3574 tsec = selinux_cred(new_creds);
3575 /* Get label from overlay inode and set it in create_sid */
3576 selinux_inode_getsecid(d_inode(src), &sid);
3577 tsec->create_sid = sid;
3578 *new = new_creds;
3579 return 0;
3580 }
3581
3582 static int selinux_inode_copy_up_xattr(const char *name)
3583 {
3584 /* The copy_up hook above sets the initial context on an inode, but we
3585 * don't then want to overwrite it by blindly copying all the lower
3586 * xattrs up. Instead, we have to filter out SELinux-related xattrs.
3587 */
3588 if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3589 return 1; /* Discard */
3590 /*
3591 * Any other attribute apart from SELINUX is not claimed, supported
3592 * by selinux.
3593 */
3594 return -EOPNOTSUPP;
3595 }
3596
3597 /* kernfs node operations */
3598
3599 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3600 struct kernfs_node *kn)
3601 {
3602 const struct task_security_struct *tsec = selinux_cred(current_cred());
3603 u32 parent_sid, newsid, clen;
3604 int rc;
3605 char *context;
3606
3607 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3608 if (rc == -ENODATA)
3609 return 0;
3610 else if (rc < 0)
3611 return rc;
3612
3613 clen = (u32)rc;
3614 context = kmalloc(clen, GFP_KERNEL);
3615 if (!context)
3616 return -ENOMEM;
3617
3618 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3619 if (rc < 0) {
3620 kfree(context);
3621 return rc;
3622 }
3623
3624 rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
3625 GFP_KERNEL);
3626 kfree(context);
3627 if (rc)
3628 return rc;
3629
3630 if (tsec->create_sid) {
3631 newsid = tsec->create_sid;
3632 } else {
3633 u16 secclass = inode_mode_to_security_class(kn->mode);
3634 struct qstr q;
3635
3636 q.name = kn->name;
3637 q.hash_len = hashlen_string(kn_dir, kn->name);
3638
3639 rc = security_transition_sid(&selinux_state, tsec->sid,
3640 parent_sid, secclass, &q,
3641 &newsid);
3642 if (rc)
3643 return rc;
3644 }
3645
3646 rc = security_sid_to_context_force(&selinux_state, newsid,
3647 &context, &clen);
3648 if (rc)
3649 return rc;
3650
3651 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3652 XATTR_CREATE);
3653 kfree(context);
3654 return rc;
3655 }
3656
3657
3658 /* file security operations */
3659
3660 static int selinux_revalidate_file_permission(struct file *file, int mask)
3661 {
3662 const struct cred *cred = current_cred();
3663 struct inode *inode = file_inode(file);
3664
3665 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3666 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3667 mask |= MAY_APPEND;
3668
3669 return file_has_perm(cred, file,
3670 file_mask_to_av(inode->i_mode, mask));
3671 }
3672
3673 static int selinux_file_permission(struct file *file, int mask)
3674 {
3675 struct inode *inode = file_inode(file);
3676 struct file_security_struct *fsec = selinux_file(file);
3677 struct inode_security_struct *isec;
3678 u32 sid = current_sid();
3679
3680 if (!mask)
3681 /* No permission to check. Existence test. */
3682 return 0;
3683
3684 isec = inode_security(inode);
3685 if (sid == fsec->sid && fsec->isid == isec->sid &&
3686 fsec->pseqno == avc_policy_seqno(&selinux_state))
3687 /* No change since file_open check. */
3688 return 0;
3689
3690 return selinux_revalidate_file_permission(file, mask);
3691 }
3692
3693 static int selinux_file_alloc_security(struct file *file)
3694 {
3695 struct file_security_struct *fsec = selinux_file(file);
3696 u32 sid = current_sid();
3697
3698 fsec->sid = sid;
3699 fsec->fown_sid = sid;
3700
3701 return 0;
3702 }
3703
3704 /*
3705 * Check whether a task has the ioctl permission and cmd
3706 * operation to an inode.
3707 */
3708 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3709 u32 requested, u16 cmd)
3710 {
3711 struct common_audit_data ad;
3712 struct file_security_struct *fsec = selinux_file(file);
3713 struct inode *inode = file_inode(file);
3714 struct inode_security_struct *isec;
3715 struct lsm_ioctlop_audit ioctl;
3716 u32 ssid = cred_sid(cred);
3717 int rc;
3718 u8 driver = cmd >> 8;
3719 u8 xperm = cmd & 0xff;
3720
3721 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3722 ad.u.op = &ioctl;
3723 ad.u.op->cmd = cmd;
3724 ad.u.op->path = file->f_path;
3725
3726 if (ssid != fsec->sid) {
3727 rc = avc_has_perm(&selinux_state,
3728 ssid, fsec->sid,
3729 SECCLASS_FD,
3730 FD__USE,
3731 &ad);
3732 if (rc)
3733 goto out;
3734 }
3735
3736 if (unlikely(IS_PRIVATE(inode)))
3737 return 0;
3738
3739 isec = inode_security(inode);
3740 rc = avc_has_extended_perms(&selinux_state,
3741 ssid, isec->sid, isec->sclass,
3742 requested, driver, xperm, &ad);
3743 out:
3744 return rc;
3745 }
3746
3747 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3748 unsigned long arg)
3749 {
3750 const struct cred *cred = current_cred();
3751 int error = 0;
3752
3753 switch (cmd) {
3754 case FIONREAD:
3755 case FIBMAP:
3756 case FIGETBSZ:
3757 case FS_IOC_GETFLAGS:
3758 case FS_IOC_GETVERSION:
3759 error = file_has_perm(cred, file, FILE__GETATTR);
3760 break;
3761
3762 case FS_IOC_SETFLAGS:
3763 case FS_IOC_SETVERSION:
3764 error = file_has_perm(cred, file, FILE__SETATTR);
3765 break;
3766
3767 /* sys_ioctl() checks */
3768 case FIONBIO:
3769 case FIOASYNC:
3770 error = file_has_perm(cred, file, 0);
3771 break;
3772
3773 case KDSKBENT:
3774 case KDSKBSENT:
3775 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3776 CAP_OPT_NONE, true);
3777 break;
3778
3779 /* default case assumes that the command will go
3780 * to the file's ioctl() function.
3781 */
3782 default:
3783 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3784 }
3785 return error;
3786 }
3787
3788 static int default_noexec __ro_after_init;
3789
3790 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3791 {
3792 const struct cred *cred = current_cred();
3793 u32 sid = cred_sid(cred);
3794 int rc = 0;
3795
3796 if (default_noexec &&
3797 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3798 (!shared && (prot & PROT_WRITE)))) {
3799 /*
3800 * We are making executable an anonymous mapping or a
3801 * private file mapping that will also be writable.
3802 * This has an additional check.
3803 */
3804 rc = avc_has_perm(&selinux_state,
3805 sid, sid, SECCLASS_PROCESS,
3806 PROCESS__EXECMEM, NULL);
3807 if (rc)
3808 goto error;
3809 }
3810
3811 if (file) {
3812 /* read access is always possible with a mapping */
3813 u32 av = FILE__READ;
3814
3815 /* write access only matters if the mapping is shared */
3816 if (shared && (prot & PROT_WRITE))
3817 av |= FILE__WRITE;
3818
3819 if (prot & PROT_EXEC)
3820 av |= FILE__EXECUTE;
3821
3822 return file_has_perm(cred, file, av);
3823 }
3824
3825 error:
3826 return rc;
3827 }
3828
3829 static int selinux_mmap_addr(unsigned long addr)
3830 {
3831 int rc = 0;
3832
3833 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3834 u32 sid = current_sid();
3835 rc = avc_has_perm(&selinux_state,
3836 sid, sid, SECCLASS_MEMPROTECT,
3837 MEMPROTECT__MMAP_ZERO, NULL);
3838 }
3839
3840 return rc;
3841 }
3842
3843 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3844 unsigned long prot, unsigned long flags)
3845 {
3846 struct common_audit_data ad;
3847 int rc;
3848
3849 if (file) {
3850 ad.type = LSM_AUDIT_DATA_FILE;
3851 ad.u.file = file;
3852 rc = inode_has_perm(current_cred(), file_inode(file),
3853 FILE__MAP, &ad);
3854 if (rc)
3855 return rc;
3856 }
3857
3858 if (checkreqprot_get(&selinux_state))
3859 prot = reqprot;
3860
3861 return file_map_prot_check(file, prot,
3862 (flags & MAP_TYPE) == MAP_SHARED);
3863 }
3864
3865 static int selinux_file_mprotect(struct vm_area_struct *vma,
3866 unsigned long reqprot,
3867 unsigned long prot)
3868 {
3869 const struct cred *cred = current_cred();
3870 u32 sid = cred_sid(cred);
3871
3872 if (checkreqprot_get(&selinux_state))
3873 prot = reqprot;
3874
3875 if (default_noexec &&
3876 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3877 int rc = 0;
3878 if (vma->vm_start >= vma->vm_mm->start_brk &&
3879 vma->vm_end <= vma->vm_mm->brk) {
3880 rc = avc_has_perm(&selinux_state,
3881 sid, sid, SECCLASS_PROCESS,
3882 PROCESS__EXECHEAP, NULL);
3883 } else if (!vma->vm_file &&
3884 ((vma->vm_start <= vma->vm_mm->start_stack &&
3885 vma->vm_end >= vma->vm_mm->start_stack) ||
3886 vma_is_stack_for_current(vma))) {
3887 rc = avc_has_perm(&selinux_state,
3888 sid, sid, SECCLASS_PROCESS,
3889 PROCESS__EXECSTACK, NULL);
3890 } else if (vma->vm_file && vma->anon_vma) {
3891 /*
3892 * We are making executable a file mapping that has
3893 * had some COW done. Since pages might have been
3894 * written, check ability to execute the possibly
3895 * modified content. This typically should only
3896 * occur for text relocations.
3897 */
3898 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3899 }
3900 if (rc)
3901 return rc;
3902 }
3903
3904 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3905 }
3906
3907 static int selinux_file_lock(struct file *file, unsigned int cmd)
3908 {
3909 const struct cred *cred = current_cred();
3910
3911 return file_has_perm(cred, file, FILE__LOCK);
3912 }
3913
3914 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3915 unsigned long arg)
3916 {
3917 const struct cred *cred = current_cred();
3918 int err = 0;
3919
3920 switch (cmd) {
3921 case F_SETFL:
3922 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3923 err = file_has_perm(cred, file, FILE__WRITE);
3924 break;
3925 }
3926 fallthrough;
3927 case F_SETOWN:
3928 case F_SETSIG:
3929 case F_GETFL:
3930 case F_GETOWN:
3931 case F_GETSIG:
3932 case F_GETOWNER_UIDS:
3933 /* Just check FD__USE permission */
3934 err = file_has_perm(cred, file, 0);
3935 break;
3936 case F_GETLK:
3937 case F_SETLK:
3938 case F_SETLKW:
3939 case F_OFD_GETLK:
3940 case F_OFD_SETLK:
3941 case F_OFD_SETLKW:
3942 #if BITS_PER_LONG == 32
3943 case F_GETLK64:
3944 case F_SETLK64:
3945 case F_SETLKW64:
3946 #endif
3947 err = file_has_perm(cred, file, FILE__LOCK);
3948 break;
3949 }
3950
3951 return err;
3952 }
3953
3954 static void selinux_file_set_fowner(struct file *file)
3955 {
3956 struct file_security_struct *fsec;
3957
3958 fsec = selinux_file(file);
3959 fsec->fown_sid = current_sid();
3960 }
3961
3962 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3963 struct fown_struct *fown, int signum)
3964 {
3965 struct file *file;
3966 u32 sid = task_sid_obj(tsk);
3967 u32 perm;
3968 struct file_security_struct *fsec;
3969
3970 /* struct fown_struct is never outside the context of a struct file */
3971 file = container_of(fown, struct file, f_owner);
3972
3973 fsec = selinux_file(file);
3974
3975 if (!signum)
3976 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3977 else
3978 perm = signal_to_av(signum);
3979
3980 return avc_has_perm(&selinux_state,
3981 fsec->fown_sid, sid,
3982 SECCLASS_PROCESS, perm, NULL);
3983 }
3984
3985 static int selinux_file_receive(struct file *file)
3986 {
3987 const struct cred *cred = current_cred();
3988
3989 return file_has_perm(cred, file, file_to_av(file));
3990 }
3991
3992 static int selinux_file_open(struct file *file)
3993 {
3994 struct file_security_struct *fsec;
3995 struct inode_security_struct *isec;
3996
3997 fsec = selinux_file(file);
3998 isec = inode_security(file_inode(file));
3999 /*
4000 * Save inode label and policy sequence number
4001 * at open-time so that selinux_file_permission
4002 * can determine whether revalidation is necessary.
4003 * Task label is already saved in the file security
4004 * struct as its SID.
4005 */
4006 fsec->isid = isec->sid;
4007 fsec->pseqno = avc_policy_seqno(&selinux_state);
4008 /*
4009 * Since the inode label or policy seqno may have changed
4010 * between the selinux_inode_permission check and the saving
4011 * of state above, recheck that access is still permitted.
4012 * Otherwise, access might never be revalidated against the
4013 * new inode label or new policy.
4014 * This check is not redundant - do not remove.
4015 */
4016 return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
4017 }
4018
4019 /* task security operations */
4020
4021 static int selinux_task_alloc(struct task_struct *task,
4022 unsigned long clone_flags)
4023 {
4024 u32 sid = current_sid();
4025
4026 return avc_has_perm(&selinux_state,
4027 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
4028 }
4029
4030 /*
4031 * prepare a new set of credentials for modification
4032 */
4033 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4034 gfp_t gfp)
4035 {
4036 const struct task_security_struct *old_tsec = selinux_cred(old);
4037 struct task_security_struct *tsec = selinux_cred(new);
4038
4039 *tsec = *old_tsec;
4040 return 0;
4041 }
4042
4043 /*
4044 * transfer the SELinux data to a blank set of creds
4045 */
4046 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4047 {
4048 const struct task_security_struct *old_tsec = selinux_cred(old);
4049 struct task_security_struct *tsec = selinux_cred(new);
4050
4051 *tsec = *old_tsec;
4052 }
4053
4054 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4055 {
4056 *secid = cred_sid(c);
4057 }
4058
4059 /*
4060 * set the security data for a kernel service
4061 * - all the creation contexts are set to unlabelled
4062 */
4063 static int selinux_kernel_act_as(struct cred *new, u32 secid)
4064 {
4065 struct task_security_struct *tsec = selinux_cred(new);
4066 u32 sid = current_sid();
4067 int ret;
4068
4069 ret = avc_has_perm(&selinux_state,
4070 sid, secid,
4071 SECCLASS_KERNEL_SERVICE,
4072 KERNEL_SERVICE__USE_AS_OVERRIDE,
4073 NULL);
4074 if (ret == 0) {
4075 tsec->sid = secid;
4076 tsec->create_sid = 0;
4077 tsec->keycreate_sid = 0;
4078 tsec->sockcreate_sid = 0;
4079 }
4080 return ret;
4081 }
4082
4083 /*
4084 * set the file creation context in a security record to the same as the
4085 * objective context of the specified inode
4086 */
4087 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4088 {
4089 struct inode_security_struct *isec = inode_security(inode);
4090 struct task_security_struct *tsec = selinux_cred(new);
4091 u32 sid = current_sid();
4092 int ret;
4093
4094 ret = avc_has_perm(&selinux_state,
4095 sid, isec->sid,
4096 SECCLASS_KERNEL_SERVICE,
4097 KERNEL_SERVICE__CREATE_FILES_AS,
4098 NULL);
4099
4100 if (ret == 0)
4101 tsec->create_sid = isec->sid;
4102 return ret;
4103 }
4104
4105 static int selinux_kernel_module_request(char *kmod_name)
4106 {
4107 struct common_audit_data ad;
4108
4109 ad.type = LSM_AUDIT_DATA_KMOD;
4110 ad.u.kmod_name = kmod_name;
4111
4112 return avc_has_perm(&selinux_state,
4113 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4114 SYSTEM__MODULE_REQUEST, &ad);
4115 }
4116
4117 static int selinux_kernel_module_from_file(struct file *file)
4118 {
4119 struct common_audit_data ad;
4120 struct inode_security_struct *isec;
4121 struct file_security_struct *fsec;
4122 u32 sid = current_sid();
4123 int rc;
4124
4125 /* init_module */
4126 if (file == NULL)
4127 return avc_has_perm(&selinux_state,
4128 sid, sid, SECCLASS_SYSTEM,
4129 SYSTEM__MODULE_LOAD, NULL);
4130
4131 /* finit_module */
4132
4133 ad.type = LSM_AUDIT_DATA_FILE;
4134 ad.u.file = file;
4135
4136 fsec = selinux_file(file);
4137 if (sid != fsec->sid) {
4138 rc = avc_has_perm(&selinux_state,
4139 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4140 if (rc)
4141 return rc;
4142 }
4143
4144 isec = inode_security(file_inode(file));
4145 return avc_has_perm(&selinux_state,
4146 sid, isec->sid, SECCLASS_SYSTEM,
4147 SYSTEM__MODULE_LOAD, &ad);
4148 }
4149
4150 static int selinux_kernel_read_file(struct file *file,
4151 enum kernel_read_file_id id,
4152 bool contents)
4153 {
4154 int rc = 0;
4155
4156 switch (id) {
4157 case READING_MODULE:
4158 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4159 break;
4160 default:
4161 break;
4162 }
4163
4164 return rc;
4165 }
4166
4167 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4168 {
4169 int rc = 0;
4170
4171 switch (id) {
4172 case LOADING_MODULE:
4173 rc = selinux_kernel_module_from_file(NULL);
4174 break;
4175 default:
4176 break;
4177 }
4178
4179 return rc;
4180 }
4181
4182 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4183 {
4184 return avc_has_perm(&selinux_state,
4185 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4186 PROCESS__SETPGID, NULL);
4187 }
4188
4189 static int selinux_task_getpgid(struct task_struct *p)
4190 {
4191 return avc_has_perm(&selinux_state,
4192 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4193 PROCESS__GETPGID, NULL);
4194 }
4195
4196 static int selinux_task_getsid(struct task_struct *p)
4197 {
4198 return avc_has_perm(&selinux_state,
4199 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4200 PROCESS__GETSESSION, NULL);
4201 }
4202
4203 static void selinux_task_getsecid_subj(struct task_struct *p, u32 *secid)
4204 {
4205 *secid = task_sid_subj(p);
4206 }
4207
4208 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid)
4209 {
4210 *secid = task_sid_obj(p);
4211 }
4212
4213 static int selinux_task_setnice(struct task_struct *p, int nice)
4214 {
4215 return avc_has_perm(&selinux_state,
4216 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4217 PROCESS__SETSCHED, NULL);
4218 }
4219
4220 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4221 {
4222 return avc_has_perm(&selinux_state,
4223 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4224 PROCESS__SETSCHED, NULL);
4225 }
4226
4227 static int selinux_task_getioprio(struct task_struct *p)
4228 {
4229 return avc_has_perm(&selinux_state,
4230 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4231 PROCESS__GETSCHED, NULL);
4232 }
4233
4234 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4235 unsigned int flags)
4236 {
4237 u32 av = 0;
4238
4239 if (!flags)
4240 return 0;
4241 if (flags & LSM_PRLIMIT_WRITE)
4242 av |= PROCESS__SETRLIMIT;
4243 if (flags & LSM_PRLIMIT_READ)
4244 av |= PROCESS__GETRLIMIT;
4245 return avc_has_perm(&selinux_state,
4246 cred_sid(cred), cred_sid(tcred),
4247 SECCLASS_PROCESS, av, NULL);
4248 }
4249
4250 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4251 struct rlimit *new_rlim)
4252 {
4253 struct rlimit *old_rlim = p->signal->rlim + resource;
4254
4255 /* Control the ability to change the hard limit (whether
4256 lowering or raising it), so that the hard limit can
4257 later be used as a safe reset point for the soft limit
4258 upon context transitions. See selinux_bprm_committing_creds. */
4259 if (old_rlim->rlim_max != new_rlim->rlim_max)
4260 return avc_has_perm(&selinux_state,
4261 current_sid(), task_sid_obj(p),
4262 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4263
4264 return 0;
4265 }
4266
4267 static int selinux_task_setscheduler(struct task_struct *p)
4268 {
4269 return avc_has_perm(&selinux_state,
4270 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4271 PROCESS__SETSCHED, NULL);
4272 }
4273
4274 static int selinux_task_getscheduler(struct task_struct *p)
4275 {
4276 return avc_has_perm(&selinux_state,
4277 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4278 PROCESS__GETSCHED, NULL);
4279 }
4280
4281 static int selinux_task_movememory(struct task_struct *p)
4282 {
4283 return avc_has_perm(&selinux_state,
4284 current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4285 PROCESS__SETSCHED, NULL);
4286 }
4287
4288 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4289 int sig, const struct cred *cred)
4290 {
4291 u32 secid;
4292 u32 perm;
4293
4294 if (!sig)
4295 perm = PROCESS__SIGNULL; /* null signal; existence test */
4296 else
4297 perm = signal_to_av(sig);
4298 if (!cred)
4299 secid = current_sid();
4300 else
4301 secid = cred_sid(cred);
4302 return avc_has_perm(&selinux_state,
4303 secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4304 }
4305
4306 static void selinux_task_to_inode(struct task_struct *p,
4307 struct inode *inode)
4308 {
4309 struct inode_security_struct *isec = selinux_inode(inode);
4310 u32 sid = task_sid_obj(p);
4311
4312 spin_lock(&isec->lock);
4313 isec->sclass = inode_mode_to_security_class(inode->i_mode);
4314 isec->sid = sid;
4315 isec->initialized = LABEL_INITIALIZED;
4316 spin_unlock(&isec->lock);
4317 }
4318
4319 /* Returns error only if unable to parse addresses */
4320 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4321 struct common_audit_data *ad, u8 *proto)
4322 {
4323 int offset, ihlen, ret = -EINVAL;
4324 struct iphdr _iph, *ih;
4325
4326 offset = skb_network_offset(skb);
4327 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4328 if (ih == NULL)
4329 goto out;
4330
4331 ihlen = ih->ihl * 4;
4332 if (ihlen < sizeof(_iph))
4333 goto out;
4334
4335 ad->u.net->v4info.saddr = ih->saddr;
4336 ad->u.net->v4info.daddr = ih->daddr;
4337 ret = 0;
4338
4339 if (proto)
4340 *proto = ih->protocol;
4341
4342 switch (ih->protocol) {
4343 case IPPROTO_TCP: {
4344 struct tcphdr _tcph, *th;
4345
4346 if (ntohs(ih->frag_off) & IP_OFFSET)
4347 break;
4348
4349 offset += ihlen;
4350 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4351 if (th == NULL)
4352 break;
4353
4354 ad->u.net->sport = th->source;
4355 ad->u.net->dport = th->dest;
4356 break;
4357 }
4358
4359 case IPPROTO_UDP: {
4360 struct udphdr _udph, *uh;
4361
4362 if (ntohs(ih->frag_off) & IP_OFFSET)
4363 break;
4364
4365 offset += ihlen;
4366 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4367 if (uh == NULL)
4368 break;
4369
4370 ad->u.net->sport = uh->source;
4371 ad->u.net->dport = uh->dest;
4372 break;
4373 }
4374
4375 case IPPROTO_DCCP: {
4376 struct dccp_hdr _dccph, *dh;
4377
4378 if (ntohs(ih->frag_off) & IP_OFFSET)
4379 break;
4380
4381 offset += ihlen;
4382 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4383 if (dh == NULL)
4384 break;
4385
4386 ad->u.net->sport = dh->dccph_sport;
4387 ad->u.net->dport = dh->dccph_dport;
4388 break;
4389 }
4390
4391 #if IS_ENABLED(CONFIG_IP_SCTP)
4392 case IPPROTO_SCTP: {
4393 struct sctphdr _sctph, *sh;
4394
4395 if (ntohs(ih->frag_off) & IP_OFFSET)
4396 break;
4397
4398 offset += ihlen;
4399 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4400 if (sh == NULL)
4401 break;
4402
4403 ad->u.net->sport = sh->source;
4404 ad->u.net->dport = sh->dest;
4405 break;
4406 }
4407 #endif
4408 default:
4409 break;
4410 }
4411 out:
4412 return ret;
4413 }
4414
4415 #if IS_ENABLED(CONFIG_IPV6)
4416
4417 /* Returns error only if unable to parse addresses */
4418 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4419 struct common_audit_data *ad, u8 *proto)
4420 {
4421 u8 nexthdr;
4422 int ret = -EINVAL, offset;
4423 struct ipv6hdr _ipv6h, *ip6;
4424 __be16 frag_off;
4425
4426 offset = skb_network_offset(skb);
4427 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4428 if (ip6 == NULL)
4429 goto out;
4430
4431 ad->u.net->v6info.saddr = ip6->saddr;
4432 ad->u.net->v6info.daddr = ip6->daddr;
4433 ret = 0;
4434
4435 nexthdr = ip6->nexthdr;
4436 offset += sizeof(_ipv6h);
4437 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4438 if (offset < 0)
4439 goto out;
4440
4441 if (proto)
4442 *proto = nexthdr;
4443
4444 switch (nexthdr) {
4445 case IPPROTO_TCP: {
4446 struct tcphdr _tcph, *th;
4447
4448 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4449 if (th == NULL)
4450 break;
4451
4452 ad->u.net->sport = th->source;
4453 ad->u.net->dport = th->dest;
4454 break;
4455 }
4456
4457 case IPPROTO_UDP: {
4458 struct udphdr _udph, *uh;
4459
4460 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4461 if (uh == NULL)
4462 break;
4463
4464 ad->u.net->sport = uh->source;
4465 ad->u.net->dport = uh->dest;
4466 break;
4467 }
4468
4469 case IPPROTO_DCCP: {
4470 struct dccp_hdr _dccph, *dh;
4471
4472 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4473 if (dh == NULL)
4474 break;
4475
4476 ad->u.net->sport = dh->dccph_sport;
4477 ad->u.net->dport = dh->dccph_dport;
4478 break;
4479 }
4480
4481 #if IS_ENABLED(CONFIG_IP_SCTP)
4482 case IPPROTO_SCTP: {
4483 struct sctphdr _sctph, *sh;
4484
4485 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4486 if (sh == NULL)
4487 break;
4488
4489 ad->u.net->sport = sh->source;
4490 ad->u.net->dport = sh->dest;
4491 break;
4492 }
4493 #endif
4494 /* includes fragments */
4495 default:
4496 break;
4497 }
4498 out:
4499 return ret;
4500 }
4501
4502 #endif /* IPV6 */
4503
4504 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4505 char **_addrp, int src, u8 *proto)
4506 {
4507 char *addrp;
4508 int ret;
4509
4510 switch (ad->u.net->family) {
4511 case PF_INET:
4512 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4513 if (ret)
4514 goto parse_error;
4515 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4516 &ad->u.net->v4info.daddr);
4517 goto okay;
4518
4519 #if IS_ENABLED(CONFIG_IPV6)
4520 case PF_INET6:
4521 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4522 if (ret)
4523 goto parse_error;
4524 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4525 &ad->u.net->v6info.daddr);
4526 goto okay;
4527 #endif /* IPV6 */
4528 default:
4529 addrp = NULL;
4530 goto okay;
4531 }
4532
4533 parse_error:
4534 pr_warn(
4535 "SELinux: failure in selinux_parse_skb(),"
4536 " unable to parse packet\n");
4537 return ret;
4538
4539 okay:
4540 if (_addrp)
4541 *_addrp = addrp;
4542 return 0;
4543 }
4544
4545 /**
4546 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4547 * @skb: the packet
4548 * @family: protocol family
4549 * @sid: the packet's peer label SID
4550 *
4551 * Description:
4552 * Check the various different forms of network peer labeling and determine
4553 * the peer label/SID for the packet; most of the magic actually occurs in
4554 * the security server function security_net_peersid_cmp(). The function
4555 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4556 * or -EACCES if @sid is invalid due to inconsistencies with the different
4557 * peer labels.
4558 *
4559 */
4560 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4561 {
4562 int err;
4563 u32 xfrm_sid;
4564 u32 nlbl_sid;
4565 u32 nlbl_type;
4566
4567 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4568 if (unlikely(err))
4569 return -EACCES;
4570 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4571 if (unlikely(err))
4572 return -EACCES;
4573
4574 err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4575 nlbl_type, xfrm_sid, sid);
4576 if (unlikely(err)) {
4577 pr_warn(
4578 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4579 " unable to determine packet's peer label\n");
4580 return -EACCES;
4581 }
4582
4583 return 0;
4584 }
4585
4586 /**
4587 * selinux_conn_sid - Determine the child socket label for a connection
4588 * @sk_sid: the parent socket's SID
4589 * @skb_sid: the packet's SID
4590 * @conn_sid: the resulting connection SID
4591 *
4592 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4593 * combined with the MLS information from @skb_sid in order to create
4594 * @conn_sid. If @skb_sid is not valid then @conn_sid is simply a copy
4595 * of @sk_sid. Returns zero on success, negative values on failure.
4596 *
4597 */
4598 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4599 {
4600 int err = 0;
4601
4602 if (skb_sid != SECSID_NULL)
4603 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4604 conn_sid);
4605 else
4606 *conn_sid = sk_sid;
4607
4608 return err;
4609 }
4610
4611 /* socket security operations */
4612
4613 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4614 u16 secclass, u32 *socksid)
4615 {
4616 if (tsec->sockcreate_sid > SECSID_NULL) {
4617 *socksid = tsec->sockcreate_sid;
4618 return 0;
4619 }
4620
4621 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4622 secclass, NULL, socksid);
4623 }
4624
4625 static int sock_has_perm(struct sock *sk, u32 perms)
4626 {
4627 struct sk_security_struct *sksec = selinux_sock(sk);
4628 struct common_audit_data ad;
4629 struct lsm_network_audit net = {0,};
4630
4631 if (sksec->sid == SECINITSID_KERNEL)
4632 return 0;
4633
4634 ad.type = LSM_AUDIT_DATA_NET;
4635 ad.u.net = &net;
4636 ad.u.net->sk = sk;
4637
4638 return avc_has_perm(&selinux_state,
4639 current_sid(), sksec->sid, sksec->sclass, perms,
4640 &ad);
4641 }
4642
4643 static int selinux_socket_create(int family, int type,
4644 int protocol, int kern)
4645 {
4646 const struct task_security_struct *tsec = selinux_cred(current_cred());
4647 u32 newsid;
4648 u16 secclass;
4649 int rc;
4650
4651 if (kern)
4652 return 0;
4653
4654 secclass = socket_type_to_security_class(family, type, protocol);
4655 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4656 if (rc)
4657 return rc;
4658
4659 return avc_has_perm(&selinux_state,
4660 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4661 }
4662
4663 static int selinux_socket_post_create(struct socket *sock, int family,
4664 int type, int protocol, int kern)
4665 {
4666 const struct task_security_struct *tsec = selinux_cred(current_cred());
4667 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4668 struct sk_security_struct *sksec;
4669 u16 sclass = socket_type_to_security_class(family, type, protocol);
4670 u32 sid = SECINITSID_KERNEL;
4671 int err = 0;
4672
4673 if (!kern) {
4674 err = socket_sockcreate_sid(tsec, sclass, &sid);
4675 if (err)
4676 return err;
4677 }
4678
4679 isec->sclass = sclass;
4680 isec->sid = sid;
4681 isec->initialized = LABEL_INITIALIZED;
4682
4683 if (sock->sk) {
4684 sksec = selinux_sock(sock->sk);
4685 sksec->sclass = sclass;
4686 sksec->sid = sid;
4687 /* Allows detection of the first association on this socket */
4688 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4689 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4690
4691 err = selinux_netlbl_socket_post_create(sock->sk, family);
4692 }
4693
4694 return err;
4695 }
4696
4697 static int selinux_socket_socketpair(struct socket *socka,
4698 struct socket *sockb)
4699 {
4700 struct sk_security_struct *sksec_a = selinux_sock(socka->sk);
4701 struct sk_security_struct *sksec_b = selinux_sock(sockb->sk);
4702
4703 sksec_a->peer_sid = sksec_b->sid;
4704 sksec_b->peer_sid = sksec_a->sid;
4705
4706 return 0;
4707 }
4708
4709 /* Range of port numbers used to automatically bind.
4710 Need to determine whether we should perform a name_bind
4711 permission check between the socket and the port number. */
4712
4713 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4714 {
4715 struct sock *sk = sock->sk;
4716 struct sk_security_struct *sksec = selinux_sock(sk);
4717 u16 family;
4718 int err;
4719
4720 err = sock_has_perm(sk, SOCKET__BIND);
4721 if (err)
4722 goto out;
4723
4724 /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4725 family = sk->sk_family;
4726 if (family == PF_INET || family == PF_INET6) {
4727 char *addrp;
4728 struct common_audit_data ad;
4729 struct lsm_network_audit net = {0,};
4730 struct sockaddr_in *addr4 = NULL;
4731 struct sockaddr_in6 *addr6 = NULL;
4732 u16 family_sa;
4733 unsigned short snum;
4734 u32 sid, node_perm;
4735
4736 /*
4737 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4738 * that validates multiple binding addresses. Because of this
4739 * need to check address->sa_family as it is possible to have
4740 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4741 */
4742 if (addrlen < offsetofend(struct sockaddr, sa_family))
4743 return -EINVAL;
4744 family_sa = address->sa_family;
4745 switch (family_sa) {
4746 case AF_UNSPEC:
4747 case AF_INET:
4748 if (addrlen < sizeof(struct sockaddr_in))
4749 return -EINVAL;
4750 addr4 = (struct sockaddr_in *)address;
4751 if (family_sa == AF_UNSPEC) {
4752 /* see __inet_bind(), we only want to allow
4753 * AF_UNSPEC if the address is INADDR_ANY
4754 */
4755 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4756 goto err_af;
4757 family_sa = AF_INET;
4758 }
4759 snum = ntohs(addr4->sin_port);
4760 addrp = (char *)&addr4->sin_addr.s_addr;
4761 break;
4762 case AF_INET6:
4763 if (addrlen < SIN6_LEN_RFC2133)
4764 return -EINVAL;
4765 addr6 = (struct sockaddr_in6 *)address;
4766 snum = ntohs(addr6->sin6_port);
4767 addrp = (char *)&addr6->sin6_addr.s6_addr;
4768 break;
4769 default:
4770 goto err_af;
4771 }
4772
4773 ad.type = LSM_AUDIT_DATA_NET;
4774 ad.u.net = &net;
4775 ad.u.net->sport = htons(snum);
4776 ad.u.net->family = family_sa;
4777
4778 if (snum) {
4779 int low, high;
4780
4781 inet_get_local_port_range(sock_net(sk), &low, &high);
4782
4783 if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4784 snum < low || snum > high) {
4785 err = sel_netport_sid(sk->sk_protocol,
4786 snum, &sid);
4787 if (err)
4788 goto out;
4789 err = avc_has_perm(&selinux_state,
4790 sksec->sid, sid,
4791 sksec->sclass,
4792 SOCKET__NAME_BIND, &ad);
4793 if (err)
4794 goto out;
4795 }
4796 }
4797
4798 switch (sksec->sclass) {
4799 case SECCLASS_TCP_SOCKET:
4800 node_perm = TCP_SOCKET__NODE_BIND;
4801 break;
4802
4803 case SECCLASS_UDP_SOCKET:
4804 node_perm = UDP_SOCKET__NODE_BIND;
4805 break;
4806
4807 case SECCLASS_DCCP_SOCKET:
4808 node_perm = DCCP_SOCKET__NODE_BIND;
4809 break;
4810
4811 case SECCLASS_SCTP_SOCKET:
4812 node_perm = SCTP_SOCKET__NODE_BIND;
4813 break;
4814
4815 default:
4816 node_perm = RAWIP_SOCKET__NODE_BIND;
4817 break;
4818 }
4819
4820 err = sel_netnode_sid(addrp, family_sa, &sid);
4821 if (err)
4822 goto out;
4823
4824 if (family_sa == AF_INET)
4825 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4826 else
4827 ad.u.net->v6info.saddr = addr6->sin6_addr;
4828
4829 err = avc_has_perm(&selinux_state,
4830 sksec->sid, sid,
4831 sksec->sclass, node_perm, &ad);
4832 if (err)
4833 goto out;
4834 }
4835 out:
4836 return err;
4837 err_af:
4838 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4839 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4840 return -EINVAL;
4841 return -EAFNOSUPPORT;
4842 }
4843
4844 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4845 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4846 */
4847 static int selinux_socket_connect_helper(struct socket *sock,
4848 struct sockaddr *address, int addrlen)
4849 {
4850 struct sock *sk = sock->sk;
4851 struct sk_security_struct *sksec = selinux_sock(sk);
4852 int err;
4853
4854 err = sock_has_perm(sk, SOCKET__CONNECT);
4855 if (err)
4856 return err;
4857 if (addrlen < offsetofend(struct sockaddr, sa_family))
4858 return -EINVAL;
4859
4860 /* connect(AF_UNSPEC) has special handling, as it is a documented
4861 * way to disconnect the socket
4862 */
4863 if (address->sa_family == AF_UNSPEC)
4864 return 0;
4865
4866 /*
4867 * If a TCP, DCCP or SCTP socket, check name_connect permission
4868 * for the port.
4869 */
4870 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4871 sksec->sclass == SECCLASS_DCCP_SOCKET ||
4872 sksec->sclass == SECCLASS_SCTP_SOCKET) {
4873 struct common_audit_data ad;
4874 struct lsm_network_audit net = {0,};
4875 struct sockaddr_in *addr4 = NULL;
4876 struct sockaddr_in6 *addr6 = NULL;
4877 unsigned short snum;
4878 u32 sid, perm;
4879
4880 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4881 * that validates multiple connect addresses. Because of this
4882 * need to check address->sa_family as it is possible to have
4883 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4884 */
4885 switch (address->sa_family) {
4886 case AF_INET:
4887 addr4 = (struct sockaddr_in *)address;
4888 if (addrlen < sizeof(struct sockaddr_in))
4889 return -EINVAL;
4890 snum = ntohs(addr4->sin_port);
4891 break;
4892 case AF_INET6:
4893 addr6 = (struct sockaddr_in6 *)address;
4894 if (addrlen < SIN6_LEN_RFC2133)
4895 return -EINVAL;
4896 snum = ntohs(addr6->sin6_port);
4897 break;
4898 default:
4899 /* Note that SCTP services expect -EINVAL, whereas
4900 * others expect -EAFNOSUPPORT.
4901 */
4902 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4903 return -EINVAL;
4904 else
4905 return -EAFNOSUPPORT;
4906 }
4907
4908 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4909 if (err)
4910 return err;
4911
4912 switch (sksec->sclass) {
4913 case SECCLASS_TCP_SOCKET:
4914 perm = TCP_SOCKET__NAME_CONNECT;
4915 break;
4916 case SECCLASS_DCCP_SOCKET:
4917 perm = DCCP_SOCKET__NAME_CONNECT;
4918 break;
4919 case SECCLASS_SCTP_SOCKET:
4920 perm = SCTP_SOCKET__NAME_CONNECT;
4921 break;
4922 }
4923
4924 ad.type = LSM_AUDIT_DATA_NET;
4925 ad.u.net = &net;
4926 ad.u.net->dport = htons(snum);
4927 ad.u.net->family = address->sa_family;
4928 err = avc_has_perm(&selinux_state,
4929 sksec->sid, sid, sksec->sclass, perm, &ad);
4930 if (err)
4931 return err;
4932 }
4933
4934 return 0;
4935 }
4936
4937 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4938 static int selinux_socket_connect(struct socket *sock,
4939 struct sockaddr *address, int addrlen)
4940 {
4941 int err;
4942 struct sock *sk = sock->sk;
4943
4944 err = selinux_socket_connect_helper(sock, address, addrlen);
4945 if (err)
4946 return err;
4947
4948 return selinux_netlbl_socket_connect(sk, address);
4949 }
4950
4951 static int selinux_socket_listen(struct socket *sock, int backlog)
4952 {
4953 return sock_has_perm(sock->sk, SOCKET__LISTEN);
4954 }
4955
4956 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4957 {
4958 int err;
4959 struct inode_security_struct *isec;
4960 struct inode_security_struct *newisec;
4961 u16 sclass;
4962 u32 sid;
4963
4964 err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4965 if (err)
4966 return err;
4967
4968 isec = inode_security_novalidate(SOCK_INODE(sock));
4969 spin_lock(&isec->lock);
4970 sclass = isec->sclass;
4971 sid = isec->sid;
4972 spin_unlock(&isec->lock);
4973
4974 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4975 newisec->sclass = sclass;
4976 newisec->sid = sid;
4977 newisec->initialized = LABEL_INITIALIZED;
4978
4979 return 0;
4980 }
4981
4982 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4983 int size)
4984 {
4985 return sock_has_perm(sock->sk, SOCKET__WRITE);
4986 }
4987
4988 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4989 int size, int flags)
4990 {
4991 return sock_has_perm(sock->sk, SOCKET__READ);
4992 }
4993
4994 static int selinux_socket_getsockname(struct socket *sock)
4995 {
4996 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4997 }
4998
4999 static int selinux_socket_getpeername(struct socket *sock)
5000 {
5001 return sock_has_perm(sock->sk, SOCKET__GETATTR);
5002 }
5003
5004 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
5005 {
5006 int err;
5007
5008 err = sock_has_perm(sock->sk, SOCKET__SETOPT);
5009 if (err)
5010 return err;
5011
5012 return selinux_netlbl_socket_setsockopt(sock, level, optname);
5013 }
5014
5015 static int selinux_socket_getsockopt(struct socket *sock, int level,
5016 int optname)
5017 {
5018 return sock_has_perm(sock->sk, SOCKET__GETOPT);
5019 }
5020
5021 static int selinux_socket_shutdown(struct socket *sock, int how)
5022 {
5023 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
5024 }
5025
5026 static int selinux_socket_unix_stream_connect(struct sock *sock,
5027 struct sock *other,
5028 struct sock *newsk)
5029 {
5030 struct sk_security_struct *sksec_sock = selinux_sock(sock);
5031 struct sk_security_struct *sksec_other = selinux_sock(other);
5032 struct sk_security_struct *sksec_new = selinux_sock(newsk);
5033 struct common_audit_data ad;
5034 struct lsm_network_audit net = {0,};
5035 int err;
5036
5037 ad.type = LSM_AUDIT_DATA_NET;
5038 ad.u.net = &net;
5039 ad.u.net->sk = other;
5040
5041 err = avc_has_perm(&selinux_state,
5042 sksec_sock->sid, sksec_other->sid,
5043 sksec_other->sclass,
5044 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5045 if (err)
5046 return err;
5047
5048 /* server child socket */
5049 sksec_new->peer_sid = sksec_sock->sid;
5050 err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
5051 sksec_sock->sid, &sksec_new->sid);
5052 if (err)
5053 return err;
5054
5055 /* connecting socket */
5056 sksec_sock->peer_sid = sksec_new->sid;
5057
5058 return 0;
5059 }
5060
5061 static int selinux_socket_unix_may_send(struct socket *sock,
5062 struct socket *other)
5063 {
5064 struct sk_security_struct *ssec = selinux_sock(sock->sk);
5065 struct sk_security_struct *osec = selinux_sock(other->sk);
5066 struct common_audit_data ad;
5067 struct lsm_network_audit net = {0,};
5068
5069 ad.type = LSM_AUDIT_DATA_NET;
5070 ad.u.net = &net;
5071 ad.u.net->sk = other->sk;
5072
5073 return avc_has_perm(&selinux_state,
5074 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5075 &ad);
5076 }
5077
5078 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5079 char *addrp, u16 family, u32 peer_sid,
5080 struct common_audit_data *ad)
5081 {
5082 int err;
5083 u32 if_sid;
5084 u32 node_sid;
5085
5086 err = sel_netif_sid(ns, ifindex, &if_sid);
5087 if (err)
5088 return err;
5089 err = avc_has_perm(&selinux_state,
5090 peer_sid, if_sid,
5091 SECCLASS_NETIF, NETIF__INGRESS, ad);
5092 if (err)
5093 return err;
5094
5095 err = sel_netnode_sid(addrp, family, &node_sid);
5096 if (err)
5097 return err;
5098 return avc_has_perm(&selinux_state,
5099 peer_sid, node_sid,
5100 SECCLASS_NODE, NODE__RECVFROM, ad);
5101 }
5102
5103 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5104 u16 family)
5105 {
5106 int err = 0;
5107 struct sk_security_struct *sksec = selinux_sock(sk);
5108 u32 sk_sid = sksec->sid;
5109 struct common_audit_data ad;
5110 struct lsm_network_audit net = {0,};
5111 char *addrp;
5112
5113 ad.type = LSM_AUDIT_DATA_NET;
5114 ad.u.net = &net;
5115 ad.u.net->netif = skb->skb_iif;
5116 ad.u.net->family = family;
5117 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5118 if (err)
5119 return err;
5120
5121 if (selinux_secmark_enabled()) {
5122 err = avc_has_perm(&selinux_state,
5123 sk_sid, skb->secmark, SECCLASS_PACKET,
5124 PACKET__RECV, &ad);
5125 if (err)
5126 return err;
5127 }
5128
5129 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5130 if (err)
5131 return err;
5132 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5133
5134 return err;
5135 }
5136
5137 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5138 {
5139 int err;
5140 struct sk_security_struct *sksec = selinux_sock(sk);
5141 u16 family = sk->sk_family;
5142 u32 sk_sid = sksec->sid;
5143 struct common_audit_data ad;
5144 struct lsm_network_audit net = {0,};
5145 char *addrp;
5146 u8 secmark_active;
5147 u8 peerlbl_active;
5148
5149 if (family != PF_INET && family != PF_INET6)
5150 return 0;
5151
5152 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5153 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5154 family = PF_INET;
5155
5156 /* If any sort of compatibility mode is enabled then handoff processing
5157 * to the selinux_sock_rcv_skb_compat() function to deal with the
5158 * special handling. We do this in an attempt to keep this function
5159 * as fast and as clean as possible. */
5160 if (!selinux_policycap_netpeer())
5161 return selinux_sock_rcv_skb_compat(sk, skb, family);
5162
5163 secmark_active = selinux_secmark_enabled();
5164 peerlbl_active = selinux_peerlbl_enabled();
5165 if (!secmark_active && !peerlbl_active)
5166 return 0;
5167
5168 ad.type = LSM_AUDIT_DATA_NET;
5169 ad.u.net = &net;
5170 ad.u.net->netif = skb->skb_iif;
5171 ad.u.net->family = family;
5172 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5173 if (err)
5174 return err;
5175
5176 if (peerlbl_active) {
5177 u32 peer_sid;
5178
5179 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5180 if (err)
5181 return err;
5182 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5183 addrp, family, peer_sid, &ad);
5184 if (err) {
5185 selinux_netlbl_err(skb, family, err, 0);
5186 return err;
5187 }
5188 err = avc_has_perm(&selinux_state,
5189 sk_sid, peer_sid, SECCLASS_PEER,
5190 PEER__RECV, &ad);
5191 if (err) {
5192 selinux_netlbl_err(skb, family, err, 0);
5193 return err;
5194 }
5195 }
5196
5197 if (secmark_active) {
5198 err = avc_has_perm(&selinux_state,
5199 sk_sid, skb->secmark, SECCLASS_PACKET,
5200 PACKET__RECV, &ad);
5201 if (err)
5202 return err;
5203 }
5204
5205 return err;
5206 }
5207
5208 static int selinux_socket_getpeersec_stream(struct socket *sock,
5209 char __user *optval,
5210 int __user *optlen,
5211 unsigned int len)
5212 {
5213 int err = 0;
5214 char *scontext;
5215 u32 scontext_len;
5216 struct sk_security_struct *sksec = selinux_sock(sock->sk);
5217 u32 peer_sid = SECSID_NULL;
5218
5219 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5220 sksec->sclass == SECCLASS_TCP_SOCKET ||
5221 sksec->sclass == SECCLASS_SCTP_SOCKET)
5222 peer_sid = sksec->peer_sid;
5223 if (peer_sid == SECSID_NULL)
5224 return -ENOPROTOOPT;
5225
5226 err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5227 &scontext_len);
5228 if (err)
5229 return err;
5230
5231 if (scontext_len > len) {
5232 err = -ERANGE;
5233 goto out_len;
5234 }
5235
5236 if (copy_to_user(optval, scontext, scontext_len))
5237 err = -EFAULT;
5238
5239 out_len:
5240 if (put_user(scontext_len, optlen))
5241 err = -EFAULT;
5242 kfree(scontext);
5243 return err;
5244 }
5245
5246 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5247 {
5248 u32 peer_secid = SECSID_NULL;
5249 u16 family;
5250 struct inode_security_struct *isec;
5251
5252 if (skb && skb->protocol == htons(ETH_P_IP))
5253 family = PF_INET;
5254 else if (skb && skb->protocol == htons(ETH_P_IPV6))
5255 family = PF_INET6;
5256 else if (sock)
5257 family = sock->sk->sk_family;
5258 else
5259 goto out;
5260
5261 if (sock && family == PF_UNIX) {
5262 isec = inode_security_novalidate(SOCK_INODE(sock));
5263 peer_secid = isec->sid;
5264 } else if (skb)
5265 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5266
5267 out:
5268 *secid = peer_secid;
5269 if (peer_secid == SECSID_NULL)
5270 return -EINVAL;
5271 return 0;
5272 }
5273
5274 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5275 {
5276 struct sk_security_struct *sksec = selinux_sock(sk);
5277
5278 sksec->peer_sid = SECINITSID_UNLABELED;
5279 sksec->sid = SECINITSID_UNLABELED;
5280 sksec->sclass = SECCLASS_SOCKET;
5281 selinux_netlbl_sk_security_reset(sksec);
5282
5283 return 0;
5284 }
5285
5286 static void selinux_sk_free_security(struct sock *sk)
5287 {
5288 struct sk_security_struct *sksec = selinux_sock(sk);
5289
5290 selinux_netlbl_sk_security_free(sksec);
5291 }
5292
5293 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5294 {
5295 struct sk_security_struct *sksec = selinux_sock(sk);
5296 struct sk_security_struct *newsksec = selinux_sock(newsk);
5297
5298 newsksec->sid = sksec->sid;
5299 newsksec->peer_sid = sksec->peer_sid;
5300 newsksec->sclass = sksec->sclass;
5301
5302 selinux_netlbl_sk_security_reset(newsksec);
5303 }
5304
5305 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5306 {
5307 if (!sk)
5308 *secid = SECINITSID_ANY_SOCKET;
5309 else {
5310 struct sk_security_struct *sksec = selinux_sock(sk);
5311
5312 *secid = sksec->sid;
5313 }
5314 }
5315
5316 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5317 {
5318 struct inode_security_struct *isec =
5319 inode_security_novalidate(SOCK_INODE(parent));
5320 struct sk_security_struct *sksec = selinux_sock(sk);
5321
5322 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5323 sk->sk_family == PF_UNIX)
5324 isec->sid = sksec->sid;
5325 sksec->sclass = isec->sclass;
5326 }
5327
5328 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5329 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5330 * already present).
5331 */
5332 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5333 struct sk_buff *skb)
5334 {
5335 struct sk_security_struct *sksec = selinux_sock(ep->base.sk);
5336 struct common_audit_data ad;
5337 struct lsm_network_audit net = {0,};
5338 u8 peerlbl_active;
5339 u32 peer_sid = SECINITSID_UNLABELED;
5340 u32 conn_sid;
5341 int err = 0;
5342
5343 if (!selinux_policycap_extsockclass())
5344 return 0;
5345
5346 peerlbl_active = selinux_peerlbl_enabled();
5347
5348 if (peerlbl_active) {
5349 /* This will return peer_sid = SECSID_NULL if there are
5350 * no peer labels, see security_net_peersid_resolve().
5351 */
5352 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5353 &peer_sid);
5354 if (err)
5355 return err;
5356
5357 if (peer_sid == SECSID_NULL)
5358 peer_sid = SECINITSID_UNLABELED;
5359 }
5360
5361 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5362 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5363
5364 /* Here as first association on socket. As the peer SID
5365 * was allowed by peer recv (and the netif/node checks),
5366 * then it is approved by policy and used as the primary
5367 * peer SID for getpeercon(3).
5368 */
5369 sksec->peer_sid = peer_sid;
5370 } else if (sksec->peer_sid != peer_sid) {
5371 /* Other association peer SIDs are checked to enforce
5372 * consistency among the peer SIDs.
5373 */
5374 ad.type = LSM_AUDIT_DATA_NET;
5375 ad.u.net = &net;
5376 ad.u.net->sk = ep->base.sk;
5377 err = avc_has_perm(&selinux_state,
5378 sksec->peer_sid, peer_sid, sksec->sclass,
5379 SCTP_SOCKET__ASSOCIATION, &ad);
5380 if (err)
5381 return err;
5382 }
5383
5384 /* Compute the MLS component for the connection and store
5385 * the information in ep. This will be used by SCTP TCP type
5386 * sockets and peeled off connections as they cause a new
5387 * socket to be generated. selinux_sctp_sk_clone() will then
5388 * plug this into the new socket.
5389 */
5390 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5391 if (err)
5392 return err;
5393
5394 ep->secid = conn_sid;
5395 ep->peer_secid = peer_sid;
5396
5397 /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5398 return selinux_netlbl_sctp_assoc_request(ep, skb);
5399 }
5400
5401 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5402 * based on their @optname.
5403 */
5404 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5405 struct sockaddr *address,
5406 int addrlen)
5407 {
5408 int len, err = 0, walk_size = 0;
5409 void *addr_buf;
5410 struct sockaddr *addr;
5411 struct socket *sock;
5412
5413 if (!selinux_policycap_extsockclass())
5414 return 0;
5415
5416 /* Process one or more addresses that may be IPv4 or IPv6 */
5417 sock = sk->sk_socket;
5418 addr_buf = address;
5419
5420 while (walk_size < addrlen) {
5421 if (walk_size + sizeof(sa_family_t) > addrlen)
5422 return -EINVAL;
5423
5424 addr = addr_buf;
5425 switch (addr->sa_family) {
5426 case AF_UNSPEC:
5427 case AF_INET:
5428 len = sizeof(struct sockaddr_in);
5429 break;
5430 case AF_INET6:
5431 len = sizeof(struct sockaddr_in6);
5432 break;
5433 default:
5434 return -EINVAL;
5435 }
5436
5437 if (walk_size + len > addrlen)
5438 return -EINVAL;
5439
5440 err = -EINVAL;
5441 switch (optname) {
5442 /* Bind checks */
5443 case SCTP_PRIMARY_ADDR:
5444 case SCTP_SET_PEER_PRIMARY_ADDR:
5445 case SCTP_SOCKOPT_BINDX_ADD:
5446 err = selinux_socket_bind(sock, addr, len);
5447 break;
5448 /* Connect checks */
5449 case SCTP_SOCKOPT_CONNECTX:
5450 case SCTP_PARAM_SET_PRIMARY:
5451 case SCTP_PARAM_ADD_IP:
5452 case SCTP_SENDMSG_CONNECT:
5453 err = selinux_socket_connect_helper(sock, addr, len);
5454 if (err)
5455 return err;
5456
5457 /* As selinux_sctp_bind_connect() is called by the
5458 * SCTP protocol layer, the socket is already locked,
5459 * therefore selinux_netlbl_socket_connect_locked()
5460 * is called here. The situations handled are:
5461 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5462 * whenever a new IP address is added or when a new
5463 * primary address is selected.
5464 * Note that an SCTP connect(2) call happens before
5465 * the SCTP protocol layer and is handled via
5466 * selinux_socket_connect().
5467 */
5468 err = selinux_netlbl_socket_connect_locked(sk, addr);
5469 break;
5470 }
5471
5472 if (err)
5473 return err;
5474
5475 addr_buf += len;
5476 walk_size += len;
5477 }
5478
5479 return 0;
5480 }
5481
5482 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5483 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5484 struct sock *newsk)
5485 {
5486 struct sk_security_struct *sksec = selinux_sock(sk);
5487 struct sk_security_struct *newsksec = selinux_sock(newsk);
5488
5489 /* If policy does not support SECCLASS_SCTP_SOCKET then call
5490 * the non-sctp clone version.
5491 */
5492 if (!selinux_policycap_extsockclass())
5493 return selinux_sk_clone_security(sk, newsk);
5494
5495 newsksec->sid = ep->secid;
5496 newsksec->peer_sid = ep->peer_secid;
5497 newsksec->sclass = sksec->sclass;
5498 selinux_netlbl_sctp_sk_clone(sk, newsk);
5499 }
5500
5501 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5502 struct request_sock *req)
5503 {
5504 struct sk_security_struct *sksec = selinux_sock(sk);
5505 int err;
5506 u16 family = req->rsk_ops->family;
5507 u32 connsid;
5508 u32 peersid;
5509
5510 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5511 if (err)
5512 return err;
5513 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5514 if (err)
5515 return err;
5516 req->secid = connsid;
5517 req->peer_secid = peersid;
5518
5519 return selinux_netlbl_inet_conn_request(req, family);
5520 }
5521
5522 static void selinux_inet_csk_clone(struct sock *newsk,
5523 const struct request_sock *req)
5524 {
5525 struct sk_security_struct *newsksec = selinux_sock(newsk);
5526
5527 newsksec->sid = req->secid;
5528 newsksec->peer_sid = req->peer_secid;
5529 /* NOTE: Ideally, we should also get the isec->sid for the
5530 new socket in sync, but we don't have the isec available yet.
5531 So we will wait until sock_graft to do it, by which
5532 time it will have been created and available. */
5533
5534 /* We don't need to take any sort of lock here as we are the only
5535 * thread with access to newsksec */
5536 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5537 }
5538
5539 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5540 {
5541 u16 family = sk->sk_family;
5542 struct sk_security_struct *sksec = selinux_sock(sk);
5543
5544 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5545 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5546 family = PF_INET;
5547
5548 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5549 }
5550
5551 static int selinux_secmark_relabel_packet(u32 sid)
5552 {
5553 const struct task_security_struct *__tsec;
5554 u32 tsid;
5555
5556 __tsec = selinux_cred(current_cred());
5557 tsid = __tsec->sid;
5558
5559 return avc_has_perm(&selinux_state,
5560 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5561 NULL);
5562 }
5563
5564 static void selinux_secmark_refcount_inc(void)
5565 {
5566 atomic_inc(&selinux_secmark_refcount);
5567 }
5568
5569 static void selinux_secmark_refcount_dec(void)
5570 {
5571 atomic_dec(&selinux_secmark_refcount);
5572 }
5573
5574 static void selinux_req_classify_flow(const struct request_sock *req,
5575 struct flowi_common *flic)
5576 {
5577 flic->flowic_secid = req->secid;
5578 }
5579
5580 static int selinux_tun_dev_alloc_security(void **security)
5581 {
5582 struct tun_security_struct *tunsec;
5583
5584 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5585 if (!tunsec)
5586 return -ENOMEM;
5587 tunsec->sid = current_sid();
5588
5589 *security = tunsec;
5590 return 0;
5591 }
5592
5593 static void selinux_tun_dev_free_security(void *security)
5594 {
5595 kfree(security);
5596 }
5597
5598 static int selinux_tun_dev_create(void)
5599 {
5600 u32 sid = current_sid();
5601
5602 /* we aren't taking into account the "sockcreate" SID since the socket
5603 * that is being created here is not a socket in the traditional sense,
5604 * instead it is a private sock, accessible only to the kernel, and
5605 * representing a wide range of network traffic spanning multiple
5606 * connections unlike traditional sockets - check the TUN driver to
5607 * get a better understanding of why this socket is special */
5608
5609 return avc_has_perm(&selinux_state,
5610 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5611 NULL);
5612 }
5613
5614 static int selinux_tun_dev_attach_queue(void *security)
5615 {
5616 struct tun_security_struct *tunsec = security;
5617
5618 return avc_has_perm(&selinux_state,
5619 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5620 TUN_SOCKET__ATTACH_QUEUE, NULL);
5621 }
5622
5623 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5624 {
5625 struct tun_security_struct *tunsec = security;
5626 struct sk_security_struct *sksec = selinux_sock(sk);
5627
5628 /* we don't currently perform any NetLabel based labeling here and it
5629 * isn't clear that we would want to do so anyway; while we could apply
5630 * labeling without the support of the TUN user the resulting labeled
5631 * traffic from the other end of the connection would almost certainly
5632 * cause confusion to the TUN user that had no idea network labeling
5633 * protocols were being used */
5634
5635 sksec->sid = tunsec->sid;
5636 sksec->sclass = SECCLASS_TUN_SOCKET;
5637
5638 return 0;
5639 }
5640
5641 static int selinux_tun_dev_open(void *security)
5642 {
5643 struct tun_security_struct *tunsec = security;
5644 u32 sid = current_sid();
5645 int err;
5646
5647 err = avc_has_perm(&selinux_state,
5648 sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5649 TUN_SOCKET__RELABELFROM, NULL);
5650 if (err)
5651 return err;
5652 err = avc_has_perm(&selinux_state,
5653 sid, sid, SECCLASS_TUN_SOCKET,
5654 TUN_SOCKET__RELABELTO, NULL);
5655 if (err)
5656 return err;
5657 tunsec->sid = sid;
5658
5659 return 0;
5660 }
5661
5662 #ifdef CONFIG_NETFILTER
5663
5664 static unsigned int selinux_ip_forward(struct sk_buff *skb,
5665 const struct net_device *indev,
5666 u16 family)
5667 {
5668 int err;
5669 char *addrp;
5670 u32 peer_sid;
5671 struct common_audit_data ad;
5672 struct lsm_network_audit net = {0,};
5673 u8 secmark_active;
5674 u8 netlbl_active;
5675 u8 peerlbl_active;
5676
5677 if (!selinux_policycap_netpeer())
5678 return NF_ACCEPT;
5679
5680 secmark_active = selinux_secmark_enabled();
5681 netlbl_active = netlbl_enabled();
5682 peerlbl_active = selinux_peerlbl_enabled();
5683 if (!secmark_active && !peerlbl_active)
5684 return NF_ACCEPT;
5685
5686 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5687 return NF_DROP;
5688
5689 ad.type = LSM_AUDIT_DATA_NET;
5690 ad.u.net = &net;
5691 ad.u.net->netif = indev->ifindex;
5692 ad.u.net->family = family;
5693 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5694 return NF_DROP;
5695
5696 if (peerlbl_active) {
5697 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5698 addrp, family, peer_sid, &ad);
5699 if (err) {
5700 selinux_netlbl_err(skb, family, err, 1);
5701 return NF_DROP;
5702 }
5703 }
5704
5705 if (secmark_active)
5706 if (avc_has_perm(&selinux_state,
5707 peer_sid, skb->secmark,
5708 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5709 return NF_DROP;
5710
5711 if (netlbl_active)
5712 /* we do this in the FORWARD path and not the POST_ROUTING
5713 * path because we want to make sure we apply the necessary
5714 * labeling before IPsec is applied so we can leverage AH
5715 * protection */
5716 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5717 return NF_DROP;
5718
5719 return NF_ACCEPT;
5720 }
5721
5722 static unsigned int selinux_ipv4_forward(void *priv,
5723 struct sk_buff *skb,
5724 const struct nf_hook_state *state)
5725 {
5726 return selinux_ip_forward(skb, state->in, PF_INET);
5727 }
5728
5729 #if IS_ENABLED(CONFIG_IPV6)
5730 static unsigned int selinux_ipv6_forward(void *priv,
5731 struct sk_buff *skb,
5732 const struct nf_hook_state *state)
5733 {
5734 return selinux_ip_forward(skb, state->in, PF_INET6);
5735 }
5736 #endif /* IPV6 */
5737
5738 static unsigned int selinux_ip_output(struct sk_buff *skb,
5739 u16 family)
5740 {
5741 struct sock *sk;
5742 u32 sid;
5743
5744 if (!netlbl_enabled())
5745 return NF_ACCEPT;
5746
5747 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5748 * because we want to make sure we apply the necessary labeling
5749 * before IPsec is applied so we can leverage AH protection */
5750 sk = skb->sk;
5751 if (sk) {
5752 struct sk_security_struct *sksec;
5753
5754 if (sk_listener(sk))
5755 /* if the socket is the listening state then this
5756 * packet is a SYN-ACK packet which means it needs to
5757 * be labeled based on the connection/request_sock and
5758 * not the parent socket. unfortunately, we can't
5759 * lookup the request_sock yet as it isn't queued on
5760 * the parent socket until after the SYN-ACK is sent.
5761 * the "solution" is to simply pass the packet as-is
5762 * as any IP option based labeling should be copied
5763 * from the initial connection request (in the IP
5764 * layer). it is far from ideal, but until we get a
5765 * security label in the packet itself this is the
5766 * best we can do. */
5767 return NF_ACCEPT;
5768
5769 /* standard practice, label using the parent socket */
5770 sksec = selinux_sock(sk);
5771 sid = sksec->sid;
5772 } else
5773 sid = SECINITSID_KERNEL;
5774 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5775 return NF_DROP;
5776
5777 return NF_ACCEPT;
5778 }
5779
5780 static unsigned int selinux_ipv4_output(void *priv,
5781 struct sk_buff *skb,
5782 const struct nf_hook_state *state)
5783 {
5784 return selinux_ip_output(skb, PF_INET);
5785 }
5786
5787 #if IS_ENABLED(CONFIG_IPV6)
5788 static unsigned int selinux_ipv6_output(void *priv,
5789 struct sk_buff *skb,
5790 const struct nf_hook_state *state)
5791 {
5792 return selinux_ip_output(skb, PF_INET6);
5793 }
5794 #endif /* IPV6 */
5795
5796 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5797 int ifindex,
5798 u16 family)
5799 {
5800 struct sock *sk = skb_to_full_sk(skb);
5801 struct sk_security_struct *sksec;
5802 struct common_audit_data ad;
5803 struct lsm_network_audit net = {0,};
5804 char *addrp;
5805 u8 proto;
5806
5807 if (sk == NULL)
5808 return NF_ACCEPT;
5809 sksec = selinux_sock(sk);
5810
5811 ad.type = LSM_AUDIT_DATA_NET;
5812 ad.u.net = &net;
5813 ad.u.net->netif = ifindex;
5814 ad.u.net->family = family;
5815 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5816 return NF_DROP;
5817
5818 if (selinux_secmark_enabled())
5819 if (avc_has_perm(&selinux_state,
5820 sksec->sid, skb->secmark,
5821 SECCLASS_PACKET, PACKET__SEND, &ad))
5822 return NF_DROP_ERR(-ECONNREFUSED);
5823
5824 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5825 return NF_DROP_ERR(-ECONNREFUSED);
5826
5827 return NF_ACCEPT;
5828 }
5829
5830 static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5831 const struct net_device *outdev,
5832 u16 family)
5833 {
5834 u32 secmark_perm;
5835 u32 peer_sid;
5836 int ifindex = outdev->ifindex;
5837 struct sock *sk;
5838 struct common_audit_data ad;
5839 struct lsm_network_audit net = {0,};
5840 char *addrp;
5841 u8 secmark_active;
5842 u8 peerlbl_active;
5843
5844 /* If any sort of compatibility mode is enabled then handoff processing
5845 * to the selinux_ip_postroute_compat() function to deal with the
5846 * special handling. We do this in an attempt to keep this function
5847 * as fast and as clean as possible. */
5848 if (!selinux_policycap_netpeer())
5849 return selinux_ip_postroute_compat(skb, ifindex, family);
5850
5851 secmark_active = selinux_secmark_enabled();
5852 peerlbl_active = selinux_peerlbl_enabled();
5853 if (!secmark_active && !peerlbl_active)
5854 return NF_ACCEPT;
5855
5856 sk = skb_to_full_sk(skb);
5857
5858 #ifdef CONFIG_XFRM
5859 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5860 * packet transformation so allow the packet to pass without any checks
5861 * since we'll have another chance to perform access control checks
5862 * when the packet is on it's final way out.
5863 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5864 * is NULL, in this case go ahead and apply access control.
5865 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5866 * TCP listening state we cannot wait until the XFRM processing
5867 * is done as we will miss out on the SA label if we do;
5868 * unfortunately, this means more work, but it is only once per
5869 * connection. */
5870 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5871 !(sk && sk_listener(sk)))
5872 return NF_ACCEPT;
5873 #endif
5874
5875 if (sk == NULL) {
5876 /* Without an associated socket the packet is either coming
5877 * from the kernel or it is being forwarded; check the packet
5878 * to determine which and if the packet is being forwarded
5879 * query the packet directly to determine the security label. */
5880 if (skb->skb_iif) {
5881 secmark_perm = PACKET__FORWARD_OUT;
5882 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5883 return NF_DROP;
5884 } else {
5885 secmark_perm = PACKET__SEND;
5886 peer_sid = SECINITSID_KERNEL;
5887 }
5888 } else if (sk_listener(sk)) {
5889 /* Locally generated packet but the associated socket is in the
5890 * listening state which means this is a SYN-ACK packet. In
5891 * this particular case the correct security label is assigned
5892 * to the connection/request_sock but unfortunately we can't
5893 * query the request_sock as it isn't queued on the parent
5894 * socket until after the SYN-ACK packet is sent; the only
5895 * viable choice is to regenerate the label like we do in
5896 * selinux_inet_conn_request(). See also selinux_ip_output()
5897 * for similar problems. */
5898 u32 skb_sid;
5899 struct sk_security_struct *sksec;
5900
5901 sksec = selinux_sock(sk);
5902 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5903 return NF_DROP;
5904 /* At this point, if the returned skb peerlbl is SECSID_NULL
5905 * and the packet has been through at least one XFRM
5906 * transformation then we must be dealing with the "final"
5907 * form of labeled IPsec packet; since we've already applied
5908 * all of our access controls on this packet we can safely
5909 * pass the packet. */
5910 if (skb_sid == SECSID_NULL) {
5911 switch (family) {
5912 case PF_INET:
5913 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5914 return NF_ACCEPT;
5915 break;
5916 case PF_INET6:
5917 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5918 return NF_ACCEPT;
5919 break;
5920 default:
5921 return NF_DROP_ERR(-ECONNREFUSED);
5922 }
5923 }
5924 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5925 return NF_DROP;
5926 secmark_perm = PACKET__SEND;
5927 } else {
5928 /* Locally generated packet, fetch the security label from the
5929 * associated socket. */
5930 struct sk_security_struct *sksec = selinux_sock(sk);
5931 peer_sid = sksec->sid;
5932 secmark_perm = PACKET__SEND;
5933 }
5934
5935 ad.type = LSM_AUDIT_DATA_NET;
5936 ad.u.net = &net;
5937 ad.u.net->netif = ifindex;
5938 ad.u.net->family = family;
5939 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5940 return NF_DROP;
5941
5942 if (secmark_active)
5943 if (avc_has_perm(&selinux_state,
5944 peer_sid, skb->secmark,
5945 SECCLASS_PACKET, secmark_perm, &ad))
5946 return NF_DROP_ERR(-ECONNREFUSED);
5947
5948 if (peerlbl_active) {
5949 u32 if_sid;
5950 u32 node_sid;
5951
5952 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5953 return NF_DROP;
5954 if (avc_has_perm(&selinux_state,
5955 peer_sid, if_sid,
5956 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5957 return NF_DROP_ERR(-ECONNREFUSED);
5958
5959 if (sel_netnode_sid(addrp, family, &node_sid))
5960 return NF_DROP;
5961 if (avc_has_perm(&selinux_state,
5962 peer_sid, node_sid,
5963 SECCLASS_NODE, NODE__SENDTO, &ad))
5964 return NF_DROP_ERR(-ECONNREFUSED);
5965 }
5966
5967 return NF_ACCEPT;
5968 }
5969
5970 static unsigned int selinux_ipv4_postroute(void *priv,
5971 struct sk_buff *skb,
5972 const struct nf_hook_state *state)
5973 {
5974 return selinux_ip_postroute(skb, state->out, PF_INET);
5975 }
5976
5977 #if IS_ENABLED(CONFIG_IPV6)
5978 static unsigned int selinux_ipv6_postroute(void *priv,
5979 struct sk_buff *skb,
5980 const struct nf_hook_state *state)
5981 {
5982 return selinux_ip_postroute(skb, state->out, PF_INET6);
5983 }
5984 #endif /* IPV6 */
5985
5986 #endif /* CONFIG_NETFILTER */
5987
5988 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5989 {
5990 int rc = 0;
5991 unsigned int msg_len;
5992 unsigned int data_len = skb->len;
5993 unsigned char *data = skb->data;
5994 struct nlmsghdr *nlh;
5995 struct sk_security_struct *sksec = selinux_sock(sk);
5996 u16 sclass = sksec->sclass;
5997 u32 perm;
5998
5999 while (data_len >= nlmsg_total_size(0)) {
6000 nlh = (struct nlmsghdr *)data;
6001
6002 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
6003 * users which means we can't reject skb's with bogus
6004 * length fields; our solution is to follow what
6005 * netlink_rcv_skb() does and simply skip processing at
6006 * messages with length fields that are clearly junk
6007 */
6008 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
6009 return 0;
6010
6011 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
6012 if (rc == 0) {
6013 rc = sock_has_perm(sk, perm);
6014 if (rc)
6015 return rc;
6016 } else if (rc == -EINVAL) {
6017 /* -EINVAL is a missing msg/perm mapping */
6018 pr_warn_ratelimited("SELinux: unrecognized netlink"
6019 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
6020 " pid=%d comm=%s\n",
6021 sk->sk_protocol, nlh->nlmsg_type,
6022 secclass_map[sclass - 1].name,
6023 task_pid_nr(current), current->comm);
6024 if (enforcing_enabled(&selinux_state) &&
6025 !security_get_allow_unknown(&selinux_state))
6026 return rc;
6027 rc = 0;
6028 } else if (rc == -ENOENT) {
6029 /* -ENOENT is a missing socket/class mapping, ignore */
6030 rc = 0;
6031 } else {
6032 return rc;
6033 }
6034
6035 /* move to the next message after applying netlink padding */
6036 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
6037 if (msg_len >= data_len)
6038 return 0;
6039 data_len -= msg_len;
6040 data += msg_len;
6041 }
6042
6043 return rc;
6044 }
6045
6046 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
6047 {
6048 isec->sclass = sclass;
6049 isec->sid = current_sid();
6050 }
6051
6052 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6053 u32 perms)
6054 {
6055 struct ipc_security_struct *isec;
6056 struct common_audit_data ad;
6057 u32 sid = current_sid();
6058
6059 isec = selinux_ipc(ipc_perms);
6060
6061 ad.type = LSM_AUDIT_DATA_IPC;
6062 ad.u.ipc_id = ipc_perms->key;
6063
6064 return avc_has_perm(&selinux_state,
6065 sid, isec->sid, isec->sclass, perms, &ad);
6066 }
6067
6068 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6069 {
6070 struct msg_security_struct *msec;
6071
6072 msec = selinux_msg_msg(msg);
6073 msec->sid = SECINITSID_UNLABELED;
6074
6075 return 0;
6076 }
6077
6078 /* message queue security operations */
6079 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6080 {
6081 struct ipc_security_struct *isec;
6082 struct common_audit_data ad;
6083 u32 sid = current_sid();
6084 int rc;
6085
6086 isec = selinux_ipc(msq);
6087 ipc_init_security(isec, SECCLASS_MSGQ);
6088
6089 ad.type = LSM_AUDIT_DATA_IPC;
6090 ad.u.ipc_id = msq->key;
6091
6092 rc = avc_has_perm(&selinux_state,
6093 sid, isec->sid, SECCLASS_MSGQ,
6094 MSGQ__CREATE, &ad);
6095 return rc;
6096 }
6097
6098 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6099 {
6100 struct ipc_security_struct *isec;
6101 struct common_audit_data ad;
6102 u32 sid = current_sid();
6103
6104 isec = selinux_ipc(msq);
6105
6106 ad.type = LSM_AUDIT_DATA_IPC;
6107 ad.u.ipc_id = msq->key;
6108
6109 return avc_has_perm(&selinux_state,
6110 sid, isec->sid, SECCLASS_MSGQ,
6111 MSGQ__ASSOCIATE, &ad);
6112 }
6113
6114 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6115 {
6116 int err;
6117 int perms;
6118
6119 switch (cmd) {
6120 case IPC_INFO:
6121 case MSG_INFO:
6122 /* No specific object, just general system-wide information. */
6123 return avc_has_perm(&selinux_state,
6124 current_sid(), SECINITSID_KERNEL,
6125 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6126 case IPC_STAT:
6127 case MSG_STAT:
6128 case MSG_STAT_ANY:
6129 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6130 break;
6131 case IPC_SET:
6132 perms = MSGQ__SETATTR;
6133 break;
6134 case IPC_RMID:
6135 perms = MSGQ__DESTROY;
6136 break;
6137 default:
6138 return 0;
6139 }
6140
6141 err = ipc_has_perm(msq, perms);
6142 return err;
6143 }
6144
6145 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6146 {
6147 struct ipc_security_struct *isec;
6148 struct msg_security_struct *msec;
6149 struct common_audit_data ad;
6150 u32 sid = current_sid();
6151 int rc;
6152
6153 isec = selinux_ipc(msq);
6154 msec = selinux_msg_msg(msg);
6155
6156 /*
6157 * First time through, need to assign label to the message
6158 */
6159 if (msec->sid == SECINITSID_UNLABELED) {
6160 /*
6161 * Compute new sid based on current process and
6162 * message queue this message will be stored in
6163 */
6164 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6165 SECCLASS_MSG, NULL, &msec->sid);
6166 if (rc)
6167 return rc;
6168 }
6169
6170 ad.type = LSM_AUDIT_DATA_IPC;
6171 ad.u.ipc_id = msq->key;
6172
6173 /* Can this process write to the queue? */
6174 rc = avc_has_perm(&selinux_state,
6175 sid, isec->sid, SECCLASS_MSGQ,
6176 MSGQ__WRITE, &ad);
6177 if (!rc)
6178 /* Can this process send the message */
6179 rc = avc_has_perm(&selinux_state,
6180 sid, msec->sid, SECCLASS_MSG,
6181 MSG__SEND, &ad);
6182 if (!rc)
6183 /* Can the message be put in the queue? */
6184 rc = avc_has_perm(&selinux_state,
6185 msec->sid, isec->sid, SECCLASS_MSGQ,
6186 MSGQ__ENQUEUE, &ad);
6187
6188 return rc;
6189 }
6190
6191 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6192 struct task_struct *target,
6193 long type, int mode)
6194 {
6195 struct ipc_security_struct *isec;
6196 struct msg_security_struct *msec;
6197 struct common_audit_data ad;
6198 u32 sid = task_sid_obj(target);
6199 int rc;
6200
6201 isec = selinux_ipc(msq);
6202 msec = selinux_msg_msg(msg);
6203
6204 ad.type = LSM_AUDIT_DATA_IPC;
6205 ad.u.ipc_id = msq->key;
6206
6207 rc = avc_has_perm(&selinux_state,
6208 sid, isec->sid,
6209 SECCLASS_MSGQ, MSGQ__READ, &ad);
6210 if (!rc)
6211 rc = avc_has_perm(&selinux_state,
6212 sid, msec->sid,
6213 SECCLASS_MSG, MSG__RECEIVE, &ad);
6214 return rc;
6215 }
6216
6217 /* Shared Memory security operations */
6218 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6219 {
6220 struct ipc_security_struct *isec;
6221 struct common_audit_data ad;
6222 u32 sid = current_sid();
6223 int rc;
6224
6225 isec = selinux_ipc(shp);
6226 ipc_init_security(isec, SECCLASS_SHM);
6227
6228 ad.type = LSM_AUDIT_DATA_IPC;
6229 ad.u.ipc_id = shp->key;
6230
6231 rc = avc_has_perm(&selinux_state,
6232 sid, isec->sid, SECCLASS_SHM,
6233 SHM__CREATE, &ad);
6234 return rc;
6235 }
6236
6237 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6238 {
6239 struct ipc_security_struct *isec;
6240 struct common_audit_data ad;
6241 u32 sid = current_sid();
6242
6243 isec = selinux_ipc(shp);
6244
6245 ad.type = LSM_AUDIT_DATA_IPC;
6246 ad.u.ipc_id = shp->key;
6247
6248 return avc_has_perm(&selinux_state,
6249 sid, isec->sid, SECCLASS_SHM,
6250 SHM__ASSOCIATE, &ad);
6251 }
6252
6253 /* Note, at this point, shp is locked down */
6254 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6255 {
6256 int perms;
6257 int err;
6258
6259 switch (cmd) {
6260 case IPC_INFO:
6261 case SHM_INFO:
6262 /* No specific object, just general system-wide information. */
6263 return avc_has_perm(&selinux_state,
6264 current_sid(), SECINITSID_KERNEL,
6265 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6266 case IPC_STAT:
6267 case SHM_STAT:
6268 case SHM_STAT_ANY:
6269 perms = SHM__GETATTR | SHM__ASSOCIATE;
6270 break;
6271 case IPC_SET:
6272 perms = SHM__SETATTR;
6273 break;
6274 case SHM_LOCK:
6275 case SHM_UNLOCK:
6276 perms = SHM__LOCK;
6277 break;
6278 case IPC_RMID:
6279 perms = SHM__DESTROY;
6280 break;
6281 default:
6282 return 0;
6283 }
6284
6285 err = ipc_has_perm(shp, perms);
6286 return err;
6287 }
6288
6289 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6290 char __user *shmaddr, int shmflg)
6291 {
6292 u32 perms;
6293
6294 if (shmflg & SHM_RDONLY)
6295 perms = SHM__READ;
6296 else
6297 perms = SHM__READ | SHM__WRITE;
6298
6299 return ipc_has_perm(shp, perms);
6300 }
6301
6302 /* Semaphore security operations */
6303 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6304 {
6305 struct ipc_security_struct *isec;
6306 struct common_audit_data ad;
6307 u32 sid = current_sid();
6308 int rc;
6309
6310 isec = selinux_ipc(sma);
6311 ipc_init_security(isec, SECCLASS_SEM);
6312
6313 ad.type = LSM_AUDIT_DATA_IPC;
6314 ad.u.ipc_id = sma->key;
6315
6316 rc = avc_has_perm(&selinux_state,
6317 sid, isec->sid, SECCLASS_SEM,
6318 SEM__CREATE, &ad);
6319 return rc;
6320 }
6321
6322 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6323 {
6324 struct ipc_security_struct *isec;
6325 struct common_audit_data ad;
6326 u32 sid = current_sid();
6327
6328 isec = selinux_ipc(sma);
6329
6330 ad.type = LSM_AUDIT_DATA_IPC;
6331 ad.u.ipc_id = sma->key;
6332
6333 return avc_has_perm(&selinux_state,
6334 sid, isec->sid, SECCLASS_SEM,
6335 SEM__ASSOCIATE, &ad);
6336 }
6337
6338 /* Note, at this point, sma is locked down */
6339 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6340 {
6341 int err;
6342 u32 perms;
6343
6344 switch (cmd) {
6345 case IPC_INFO:
6346 case SEM_INFO:
6347 /* No specific object, just general system-wide information. */
6348 return avc_has_perm(&selinux_state,
6349 current_sid(), SECINITSID_KERNEL,
6350 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6351 case GETPID:
6352 case GETNCNT:
6353 case GETZCNT:
6354 perms = SEM__GETATTR;
6355 break;
6356 case GETVAL:
6357 case GETALL:
6358 perms = SEM__READ;
6359 break;
6360 case SETVAL:
6361 case SETALL:
6362 perms = SEM__WRITE;
6363 break;
6364 case IPC_RMID:
6365 perms = SEM__DESTROY;
6366 break;
6367 case IPC_SET:
6368 perms = SEM__SETATTR;
6369 break;
6370 case IPC_STAT:
6371 case SEM_STAT:
6372 case SEM_STAT_ANY:
6373 perms = SEM__GETATTR | SEM__ASSOCIATE;
6374 break;
6375 default:
6376 return 0;
6377 }
6378
6379 err = ipc_has_perm(sma, perms);
6380 return err;
6381 }
6382
6383 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6384 struct sembuf *sops, unsigned nsops, int alter)
6385 {
6386 u32 perms;
6387
6388 if (alter)
6389 perms = SEM__READ | SEM__WRITE;
6390 else
6391 perms = SEM__READ;
6392
6393 return ipc_has_perm(sma, perms);
6394 }
6395
6396 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6397 {
6398 u32 av = 0;
6399
6400 av = 0;
6401 if (flag & S_IRUGO)
6402 av |= IPC__UNIX_READ;
6403 if (flag & S_IWUGO)
6404 av |= IPC__UNIX_WRITE;
6405
6406 if (av == 0)
6407 return 0;
6408
6409 return ipc_has_perm(ipcp, av);
6410 }
6411
6412 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6413 {
6414 struct ipc_security_struct *isec = selinux_ipc(ipcp);
6415 *secid = isec->sid;
6416 }
6417
6418 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6419 {
6420 if (inode)
6421 inode_doinit_with_dentry(inode, dentry);
6422 }
6423
6424 static int selinux_getprocattr(struct task_struct *p,
6425 char *name, char **value)
6426 {
6427 const struct task_security_struct *__tsec;
6428 u32 sid;
6429 int error;
6430 unsigned len;
6431
6432 rcu_read_lock();
6433 __tsec = selinux_cred(__task_cred(p));
6434
6435 if (current != p) {
6436 error = avc_has_perm(&selinux_state,
6437 current_sid(), __tsec->sid,
6438 SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6439 if (error)
6440 goto bad;
6441 }
6442
6443 if (!strcmp(name, "current") || !strcmp(name, "context"))
6444 sid = __tsec->sid;
6445 else if (!strcmp(name, "prev"))
6446 sid = __tsec->osid;
6447 else if (!strcmp(name, "exec"))
6448 sid = __tsec->exec_sid;
6449 else if (!strcmp(name, "fscreate"))
6450 sid = __tsec->create_sid;
6451 else if (!strcmp(name, "keycreate"))
6452 sid = __tsec->keycreate_sid;
6453 else if (!strcmp(name, "sockcreate"))
6454 sid = __tsec->sockcreate_sid;
6455 else {
6456 error = -EINVAL;
6457 goto bad;
6458 }
6459 rcu_read_unlock();
6460
6461 if (!sid)
6462 return 0;
6463
6464 error = security_sid_to_context(&selinux_state, sid, value, &len);
6465 if (error)
6466 return error;
6467 return len;
6468
6469 bad:
6470 rcu_read_unlock();
6471 return error;
6472 }
6473
6474 static int selinux_setprocattr(const char *name, void *value, size_t size)
6475 {
6476 struct task_security_struct *tsec;
6477 struct cred *new;
6478 u32 mysid = current_sid(), sid = 0, ptsid;
6479 int error;
6480 char *str = value;
6481
6482 /*
6483 * Basic control over ability to set these attributes at all.
6484 */
6485
6486 /*
6487 * For setting display, we only perform a permission check;
6488 * the actual update to the display value is handled by the
6489 * LSM framework.
6490 */
6491 if (!strcmp(name, "display"))
6492 return avc_has_perm(&selinux_state,
6493 mysid, mysid, SECCLASS_PROCESS2,
6494 PROCESS2__SETDISPLAY, NULL);
6495
6496 if (!strcmp(name, "exec"))
6497 error = avc_has_perm(&selinux_state,
6498 mysid, mysid, SECCLASS_PROCESS,
6499 PROCESS__SETEXEC, NULL);
6500 else if (!strcmp(name, "fscreate"))
6501 error = avc_has_perm(&selinux_state,
6502 mysid, mysid, SECCLASS_PROCESS,
6503 PROCESS__SETFSCREATE, NULL);
6504 else if (!strcmp(name, "keycreate"))
6505 error = avc_has_perm(&selinux_state,
6506 mysid, mysid, SECCLASS_PROCESS,
6507 PROCESS__SETKEYCREATE, NULL);
6508 else if (!strcmp(name, "sockcreate"))
6509 error = avc_has_perm(&selinux_state,
6510 mysid, mysid, SECCLASS_PROCESS,
6511 PROCESS__SETSOCKCREATE, NULL);
6512 else if (!strcmp(name, "current"))
6513 error = avc_has_perm(&selinux_state,
6514 mysid, mysid, SECCLASS_PROCESS,
6515 PROCESS__SETCURRENT, NULL);
6516 else
6517 error = -EINVAL;
6518 if (error)
6519 return error;
6520
6521 /* Obtain a SID for the context, if one was specified. */
6522 if (size && str[0] && str[0] != '\n') {
6523 if (str[size-1] == '\n') {
6524 str[size-1] = 0;
6525 size--;
6526 }
6527 error = security_context_to_sid(&selinux_state, value, size,
6528 &sid, GFP_KERNEL);
6529 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6530 if (!has_cap_mac_admin(true)) {
6531 struct audit_buffer *ab;
6532 size_t audit_size;
6533
6534 /* We strip a nul only if it is at the end, otherwise the
6535 * context contains a nul and we should audit that */
6536 if (str[size - 1] == '\0')
6537 audit_size = size - 1;
6538 else
6539 audit_size = size;
6540 ab = audit_log_start(audit_context(),
6541 GFP_ATOMIC,
6542 AUDIT_SELINUX_ERR);
6543 if (!ab)
6544 return error;
6545 audit_log_format(ab, "op=fscreate invalid_context=");
6546 audit_log_n_untrustedstring(ab, value, audit_size);
6547 audit_log_end(ab);
6548
6549 return error;
6550 }
6551 error = security_context_to_sid_force(
6552 &selinux_state,
6553 value, size, &sid);
6554 }
6555 if (error)
6556 return error;
6557 }
6558
6559 new = prepare_creds();
6560 if (!new)
6561 return -ENOMEM;
6562
6563 /* Permission checking based on the specified context is
6564 performed during the actual operation (execve,
6565 open/mkdir/...), when we know the full context of the
6566 operation. See selinux_bprm_creds_for_exec for the execve
6567 checks and may_create for the file creation checks. The
6568 operation will then fail if the context is not permitted. */
6569 tsec = selinux_cred(new);
6570 if (!strcmp(name, "exec")) {
6571 tsec->exec_sid = sid;
6572 } else if (!strcmp(name, "fscreate")) {
6573 tsec->create_sid = sid;
6574 } else if (!strcmp(name, "keycreate")) {
6575 if (sid) {
6576 error = avc_has_perm(&selinux_state, mysid, sid,
6577 SECCLASS_KEY, KEY__CREATE, NULL);
6578 if (error)
6579 goto abort_change;
6580 }
6581 tsec->keycreate_sid = sid;
6582 } else if (!strcmp(name, "sockcreate")) {
6583 tsec->sockcreate_sid = sid;
6584 } else if (!strcmp(name, "current")) {
6585 error = -EINVAL;
6586 if (sid == 0)
6587 goto abort_change;
6588
6589 /* Only allow single threaded processes to change context */
6590 error = -EPERM;
6591 if (!current_is_single_threaded()) {
6592 error = security_bounded_transition(&selinux_state,
6593 tsec->sid, sid);
6594 if (error)
6595 goto abort_change;
6596 }
6597
6598 /* Check permissions for the transition. */
6599 error = avc_has_perm(&selinux_state,
6600 tsec->sid, sid, SECCLASS_PROCESS,
6601 PROCESS__DYNTRANSITION, NULL);
6602 if (error)
6603 goto abort_change;
6604
6605 /* Check for ptracing, and update the task SID if ok.
6606 Otherwise, leave SID unchanged and fail. */
6607 ptsid = ptrace_parent_sid();
6608 if (ptsid != 0) {
6609 error = avc_has_perm(&selinux_state,
6610 ptsid, sid, SECCLASS_PROCESS,
6611 PROCESS__PTRACE, NULL);
6612 if (error)
6613 goto abort_change;
6614 }
6615
6616 tsec->sid = sid;
6617 } else {
6618 error = -EINVAL;
6619 goto abort_change;
6620 }
6621
6622 commit_creds(new);
6623 return size;
6624
6625 abort_change:
6626 abort_creds(new);
6627 return error;
6628 }
6629
6630 static int selinux_ismaclabel(const char *name)
6631 {
6632 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6633 }
6634
6635 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6636 {
6637 return security_sid_to_context(&selinux_state, secid,
6638 secdata, seclen);
6639 }
6640
6641 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6642 {
6643 return security_context_to_sid(&selinux_state, secdata, seclen,
6644 secid, GFP_KERNEL);
6645 }
6646
6647 static void selinux_release_secctx(char *secdata, u32 seclen)
6648 {
6649 kfree(secdata);
6650 }
6651
6652 static void selinux_inode_invalidate_secctx(struct inode *inode)
6653 {
6654 struct inode_security_struct *isec = selinux_inode(inode);
6655
6656 spin_lock(&isec->lock);
6657 isec->initialized = LABEL_INVALID;
6658 spin_unlock(&isec->lock);
6659 }
6660
6661 /*
6662 * called with inode->i_mutex locked
6663 */
6664 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6665 {
6666 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6667 ctx, ctxlen, 0);
6668 /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6669 return rc == -EOPNOTSUPP ? 0 : rc;
6670 }
6671
6672 /*
6673 * called with inode->i_mutex locked
6674 */
6675 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6676 {
6677 return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SELINUX,
6678 ctx, ctxlen, 0);
6679 }
6680
6681 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6682 {
6683 int len = 0;
6684 len = selinux_inode_getsecurity(&init_user_ns, inode,
6685 XATTR_SELINUX_SUFFIX, ctx, true);
6686 if (len < 0)
6687 return len;
6688 *ctxlen = len;
6689 return 0;
6690 }
6691 #ifdef CONFIG_KEYS
6692
6693 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6694 unsigned long flags)
6695 {
6696 const struct task_security_struct *tsec;
6697 struct key_security_struct *ksec;
6698
6699 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6700 if (!ksec)
6701 return -ENOMEM;
6702
6703 tsec = selinux_cred(cred);
6704 if (tsec->keycreate_sid)
6705 ksec->sid = tsec->keycreate_sid;
6706 else
6707 ksec->sid = tsec->sid;
6708
6709 k->security = ksec;
6710 return 0;
6711 }
6712
6713 static void selinux_key_free(struct key *k)
6714 {
6715 struct key_security_struct *ksec = k->security;
6716
6717 k->security = NULL;
6718 kfree(ksec);
6719 }
6720
6721 static int selinux_key_permission(key_ref_t key_ref,
6722 const struct cred *cred,
6723 enum key_need_perm need_perm)
6724 {
6725 struct key *key;
6726 struct key_security_struct *ksec;
6727 u32 perm, sid;
6728
6729 switch (need_perm) {
6730 case KEY_NEED_VIEW:
6731 perm = KEY__VIEW;
6732 break;
6733 case KEY_NEED_READ:
6734 perm = KEY__READ;
6735 break;
6736 case KEY_NEED_WRITE:
6737 perm = KEY__WRITE;
6738 break;
6739 case KEY_NEED_SEARCH:
6740 perm = KEY__SEARCH;
6741 break;
6742 case KEY_NEED_LINK:
6743 perm = KEY__LINK;
6744 break;
6745 case KEY_NEED_SETATTR:
6746 perm = KEY__SETATTR;
6747 break;
6748 case KEY_NEED_UNLINK:
6749 case KEY_SYSADMIN_OVERRIDE:
6750 case KEY_AUTHTOKEN_OVERRIDE:
6751 case KEY_DEFER_PERM_CHECK:
6752 return 0;
6753 default:
6754 WARN_ON(1);
6755 return -EPERM;
6756
6757 }
6758
6759 sid = cred_sid(cred);
6760 key = key_ref_to_ptr(key_ref);
6761 ksec = key->security;
6762
6763 return avc_has_perm(&selinux_state,
6764 sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6765 }
6766
6767 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6768 {
6769 struct key_security_struct *ksec = key->security;
6770 char *context = NULL;
6771 unsigned len;
6772 int rc;
6773
6774 rc = security_sid_to_context(&selinux_state, ksec->sid,
6775 &context, &len);
6776 if (!rc)
6777 rc = len;
6778 *_buffer = context;
6779 return rc;
6780 }
6781
6782 #ifdef CONFIG_KEY_NOTIFICATIONS
6783 static int selinux_watch_key(struct key *key)
6784 {
6785 struct key_security_struct *ksec = key->security;
6786 u32 sid = current_sid();
6787
6788 return avc_has_perm(&selinux_state,
6789 sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6790 }
6791 #endif
6792 #endif
6793
6794 #ifdef CONFIG_SECURITY_INFINIBAND
6795 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6796 {
6797 struct common_audit_data ad;
6798 int err;
6799 u32 sid = 0;
6800 struct ib_security_struct *sec = ib_sec;
6801 struct lsm_ibpkey_audit ibpkey;
6802
6803 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6804 if (err)
6805 return err;
6806
6807 ad.type = LSM_AUDIT_DATA_IBPKEY;
6808 ibpkey.subnet_prefix = subnet_prefix;
6809 ibpkey.pkey = pkey_val;
6810 ad.u.ibpkey = &ibpkey;
6811 return avc_has_perm(&selinux_state,
6812 sec->sid, sid,
6813 SECCLASS_INFINIBAND_PKEY,
6814 INFINIBAND_PKEY__ACCESS, &ad);
6815 }
6816
6817 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6818 u8 port_num)
6819 {
6820 struct common_audit_data ad;
6821 int err;
6822 u32 sid = 0;
6823 struct ib_security_struct *sec = ib_sec;
6824 struct lsm_ibendport_audit ibendport;
6825
6826 err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6827 &sid);
6828
6829 if (err)
6830 return err;
6831
6832 ad.type = LSM_AUDIT_DATA_IBENDPORT;
6833 ibendport.dev_name = dev_name;
6834 ibendport.port = port_num;
6835 ad.u.ibendport = &ibendport;
6836 return avc_has_perm(&selinux_state,
6837 sec->sid, sid,
6838 SECCLASS_INFINIBAND_ENDPORT,
6839 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6840 }
6841
6842 static int selinux_ib_alloc_security(void **ib_sec)
6843 {
6844 struct ib_security_struct *sec;
6845
6846 sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6847 if (!sec)
6848 return -ENOMEM;
6849 sec->sid = current_sid();
6850
6851 *ib_sec = sec;
6852 return 0;
6853 }
6854
6855 static void selinux_ib_free_security(void *ib_sec)
6856 {
6857 kfree(ib_sec);
6858 }
6859 #endif
6860
6861 #ifdef CONFIG_BPF_SYSCALL
6862 static int selinux_bpf(int cmd, union bpf_attr *attr,
6863 unsigned int size)
6864 {
6865 u32 sid = current_sid();
6866 int ret;
6867
6868 switch (cmd) {
6869 case BPF_MAP_CREATE:
6870 ret = avc_has_perm(&selinux_state,
6871 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6872 NULL);
6873 break;
6874 case BPF_PROG_LOAD:
6875 ret = avc_has_perm(&selinux_state,
6876 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6877 NULL);
6878 break;
6879 default:
6880 ret = 0;
6881 break;
6882 }
6883
6884 return ret;
6885 }
6886
6887 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6888 {
6889 u32 av = 0;
6890
6891 if (fmode & FMODE_READ)
6892 av |= BPF__MAP_READ;
6893 if (fmode & FMODE_WRITE)
6894 av |= BPF__MAP_WRITE;
6895 return av;
6896 }
6897
6898 /* This function will check the file pass through unix socket or binder to see
6899 * if it is a bpf related object. And apply correspinding checks on the bpf
6900 * object based on the type. The bpf maps and programs, not like other files and
6901 * socket, are using a shared anonymous inode inside the kernel as their inode.
6902 * So checking that inode cannot identify if the process have privilege to
6903 * access the bpf object and that's why we have to add this additional check in
6904 * selinux_file_receive and selinux_binder_transfer_files.
6905 */
6906 static int bpf_fd_pass(struct file *file, u32 sid)
6907 {
6908 struct bpf_security_struct *bpfsec;
6909 struct bpf_prog *prog;
6910 struct bpf_map *map;
6911 int ret;
6912
6913 if (file->f_op == &bpf_map_fops) {
6914 map = file->private_data;
6915 bpfsec = map->security;
6916 ret = avc_has_perm(&selinux_state,
6917 sid, bpfsec->sid, SECCLASS_BPF,
6918 bpf_map_fmode_to_av(file->f_mode), NULL);
6919 if (ret)
6920 return ret;
6921 } else if (file->f_op == &bpf_prog_fops) {
6922 prog = file->private_data;
6923 bpfsec = prog->aux->security;
6924 ret = avc_has_perm(&selinux_state,
6925 sid, bpfsec->sid, SECCLASS_BPF,
6926 BPF__PROG_RUN, NULL);
6927 if (ret)
6928 return ret;
6929 }
6930 return 0;
6931 }
6932
6933 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6934 {
6935 u32 sid = current_sid();
6936 struct bpf_security_struct *bpfsec;
6937
6938 bpfsec = map->security;
6939 return avc_has_perm(&selinux_state,
6940 sid, bpfsec->sid, SECCLASS_BPF,
6941 bpf_map_fmode_to_av(fmode), NULL);
6942 }
6943
6944 static int selinux_bpf_prog(struct bpf_prog *prog)
6945 {
6946 u32 sid = current_sid();
6947 struct bpf_security_struct *bpfsec;
6948
6949 bpfsec = prog->aux->security;
6950 return avc_has_perm(&selinux_state,
6951 sid, bpfsec->sid, SECCLASS_BPF,
6952 BPF__PROG_RUN, NULL);
6953 }
6954
6955 static int selinux_bpf_map_alloc(struct bpf_map *map)
6956 {
6957 struct bpf_security_struct *bpfsec;
6958
6959 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6960 if (!bpfsec)
6961 return -ENOMEM;
6962
6963 bpfsec->sid = current_sid();
6964 map->security = bpfsec;
6965
6966 return 0;
6967 }
6968
6969 static void selinux_bpf_map_free(struct bpf_map *map)
6970 {
6971 struct bpf_security_struct *bpfsec = map->security;
6972
6973 map->security = NULL;
6974 kfree(bpfsec);
6975 }
6976
6977 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6978 {
6979 struct bpf_security_struct *bpfsec;
6980
6981 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6982 if (!bpfsec)
6983 return -ENOMEM;
6984
6985 bpfsec->sid = current_sid();
6986 aux->security = bpfsec;
6987
6988 return 0;
6989 }
6990
6991 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6992 {
6993 struct bpf_security_struct *bpfsec = aux->security;
6994
6995 aux->security = NULL;
6996 kfree(bpfsec);
6997 }
6998 #endif
6999
7000 static int selinux_lockdown(enum lockdown_reason what)
7001 {
7002 struct common_audit_data ad;
7003 u32 sid = current_sid();
7004 int invalid_reason = (what <= LOCKDOWN_NONE) ||
7005 (what == LOCKDOWN_INTEGRITY_MAX) ||
7006 (what >= LOCKDOWN_CONFIDENTIALITY_MAX);
7007
7008 if (WARN(invalid_reason, "Invalid lockdown reason")) {
7009 audit_log(audit_context(),
7010 GFP_ATOMIC, AUDIT_SELINUX_ERR,
7011 "lockdown_reason=invalid");
7012 return -EINVAL;
7013 }
7014
7015 ad.type = LSM_AUDIT_DATA_LOCKDOWN;
7016 ad.u.reason = what;
7017
7018 if (what <= LOCKDOWN_INTEGRITY_MAX)
7019 return avc_has_perm(&selinux_state,
7020 sid, sid, SECCLASS_LOCKDOWN,
7021 LOCKDOWN__INTEGRITY, &ad);
7022 else
7023 return avc_has_perm(&selinux_state,
7024 sid, sid, SECCLASS_LOCKDOWN,
7025 LOCKDOWN__CONFIDENTIALITY, &ad);
7026 }
7027
7028 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
7029 .lbs_cred = sizeof(struct task_security_struct),
7030 .lbs_file = sizeof(struct file_security_struct),
7031 .lbs_inode = sizeof(struct inode_security_struct),
7032 .lbs_ipc = sizeof(struct ipc_security_struct),
7033 .lbs_msg_msg = sizeof(struct msg_security_struct),
7034 .lbs_superblock = sizeof(struct superblock_security_struct),
7035 .lbs_sock = sizeof(struct sk_security_struct),
7036 };
7037
7038 #ifdef CONFIG_PERF_EVENTS
7039 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
7040 {
7041 u32 requested, sid = current_sid();
7042
7043 if (type == PERF_SECURITY_OPEN)
7044 requested = PERF_EVENT__OPEN;
7045 else if (type == PERF_SECURITY_CPU)
7046 requested = PERF_EVENT__CPU;
7047 else if (type == PERF_SECURITY_KERNEL)
7048 requested = PERF_EVENT__KERNEL;
7049 else if (type == PERF_SECURITY_TRACEPOINT)
7050 requested = PERF_EVENT__TRACEPOINT;
7051 else
7052 return -EINVAL;
7053
7054 return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT,
7055 requested, NULL);
7056 }
7057
7058 static int selinux_perf_event_alloc(struct perf_event *event)
7059 {
7060 struct perf_event_security_struct *perfsec;
7061
7062 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
7063 if (!perfsec)
7064 return -ENOMEM;
7065
7066 perfsec->sid = current_sid();
7067 event->security = perfsec;
7068
7069 return 0;
7070 }
7071
7072 static void selinux_perf_event_free(struct perf_event *event)
7073 {
7074 struct perf_event_security_struct *perfsec = event->security;
7075
7076 event->security = NULL;
7077 kfree(perfsec);
7078 }
7079
7080 static int selinux_perf_event_read(struct perf_event *event)
7081 {
7082 struct perf_event_security_struct *perfsec = event->security;
7083 u32 sid = current_sid();
7084
7085 return avc_has_perm(&selinux_state, sid, perfsec->sid,
7086 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7087 }
7088
7089 static int selinux_perf_event_write(struct perf_event *event)
7090 {
7091 struct perf_event_security_struct *perfsec = event->security;
7092 u32 sid = current_sid();
7093
7094 return avc_has_perm(&selinux_state, sid, perfsec->sid,
7095 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7096 }
7097 #endif
7098
7099 struct lsm_id selinux_lsmid __lsm_ro_after_init = {
7100 .lsm = "selinux",
7101 .slot = LSMBLOB_NEEDED
7102 };
7103
7104 /*
7105 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7106 * 1. any hooks that don't belong to (2.) or (3.) below,
7107 * 2. hooks that both access structures allocated by other hooks, and allocate
7108 * structures that can be later accessed by other hooks (mostly "cloning"
7109 * hooks),
7110 * 3. hooks that only allocate structures that can be later accessed by other
7111 * hooks ("allocating" hooks).
7112 *
7113 * Please follow block comment delimiters in the list to keep this order.
7114 *
7115 * This ordering is needed for SELinux runtime disable to work at least somewhat
7116 * safely. Breaking the ordering rules above might lead to NULL pointer derefs
7117 * when disabling SELinux at runtime.
7118 */
7119 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
7120 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7121 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7122 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7123 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7124
7125 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7126 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7127 LSM_HOOK_INIT(capget, selinux_capget),
7128 LSM_HOOK_INIT(capset, selinux_capset),
7129 LSM_HOOK_INIT(capable, selinux_capable),
7130 LSM_HOOK_INIT(quotactl, selinux_quotactl),
7131 LSM_HOOK_INIT(quota_on, selinux_quota_on),
7132 LSM_HOOK_INIT(syslog, selinux_syslog),
7133 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7134
7135 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7136
7137 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7138 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7139 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7140
7141 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7142 LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7143 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7144 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7145 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7146 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7147 LSM_HOOK_INIT(sb_mount, selinux_mount),
7148 LSM_HOOK_INIT(sb_umount, selinux_umount),
7149 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7150 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7151
7152 LSM_HOOK_INIT(move_mount, selinux_move_mount),
7153
7154 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7155 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7156
7157 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7158 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7159 LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7160 LSM_HOOK_INIT(inode_create, selinux_inode_create),
7161 LSM_HOOK_INIT(inode_link, selinux_inode_link),
7162 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7163 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7164 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7165 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7166 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7167 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7168 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7169 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7170 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7171 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7172 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7173 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7174 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7175 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7176 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7177 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7178 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7179 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7180 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7181 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7182 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7183 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7184 LSM_HOOK_INIT(path_notify, selinux_path_notify),
7185
7186 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7187
7188 LSM_HOOK_INIT(file_permission, selinux_file_permission),
7189 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7190 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7191 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7192 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7193 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7194 LSM_HOOK_INIT(file_lock, selinux_file_lock),
7195 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7196 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7197 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7198 LSM_HOOK_INIT(file_receive, selinux_file_receive),
7199
7200 LSM_HOOK_INIT(file_open, selinux_file_open),
7201
7202 LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7203 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7204 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7205 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7206 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7207 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7208 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7209 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7210 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7211 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7212 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7213 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7214 LSM_HOOK_INIT(task_getsecid_subj, selinux_task_getsecid_subj),
7215 LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj),
7216 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7217 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7218 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7219 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7220 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7221 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7222 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7223 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7224 LSM_HOOK_INIT(task_kill, selinux_task_kill),
7225 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7226
7227 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7228 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7229
7230 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7231 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7232 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7233 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7234
7235 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7236 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7237 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7238
7239 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7240 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7241 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7242
7243 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7244
7245 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7246 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7247
7248 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7249 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7250 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7251 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7252 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7253 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7254
7255 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7256 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7257
7258 LSM_HOOK_INIT(socket_create, selinux_socket_create),
7259 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7260 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7261 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7262 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7263 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7264 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7265 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7266 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7267 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7268 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7269 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7270 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7271 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7272 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7273 LSM_HOOK_INIT(socket_getpeersec_stream,
7274 selinux_socket_getpeersec_stream),
7275 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7276 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7277 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7278 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7279 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7280 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7281 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7282 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7283 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7284 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7285 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7286 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7287 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7288 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7289 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7290 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7291 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7292 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7293 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7294 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7295 #ifdef CONFIG_SECURITY_INFINIBAND
7296 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7297 LSM_HOOK_INIT(ib_endport_manage_subnet,
7298 selinux_ib_endport_manage_subnet),
7299 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7300 #endif
7301 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7302 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7303 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7304 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7305 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7306 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7307 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7308 selinux_xfrm_state_pol_flow_match),
7309 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7310 #endif
7311
7312 #ifdef CONFIG_KEYS
7313 LSM_HOOK_INIT(key_free, selinux_key_free),
7314 LSM_HOOK_INIT(key_permission, selinux_key_permission),
7315 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7316 #ifdef CONFIG_KEY_NOTIFICATIONS
7317 LSM_HOOK_INIT(watch_key, selinux_watch_key),
7318 #endif
7319 #endif
7320
7321 #ifdef CONFIG_AUDIT
7322 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7323 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7324 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7325 #endif
7326
7327 #ifdef CONFIG_BPF_SYSCALL
7328 LSM_HOOK_INIT(bpf, selinux_bpf),
7329 LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7330 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7331 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7332 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7333 #endif
7334
7335 #ifdef CONFIG_PERF_EVENTS
7336 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7337 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7338 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7339 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7340 #endif
7341
7342 LSM_HOOK_INIT(locked_down, selinux_lockdown),
7343
7344 /*
7345 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7346 */
7347 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7348 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7349 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7350 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
7351 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7352 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7353 #endif
7354
7355 /*
7356 * PUT "ALLOCATING" HOOKS HERE
7357 */
7358 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7359 LSM_HOOK_INIT(msg_queue_alloc_security,
7360 selinux_msg_queue_alloc_security),
7361 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7362 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7363 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7364 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7365 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7366 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7367 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7368 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7369 #ifdef CONFIG_SECURITY_INFINIBAND
7370 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7371 #endif
7372 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7373 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7374 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7375 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7376 selinux_xfrm_state_alloc_acquire),
7377 #endif
7378 #ifdef CONFIG_KEYS
7379 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7380 #endif
7381 #ifdef CONFIG_AUDIT
7382 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7383 #endif
7384 #ifdef CONFIG_BPF_SYSCALL
7385 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7386 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7387 #endif
7388 #ifdef CONFIG_PERF_EVENTS
7389 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7390 #endif
7391 };
7392
7393 static __init int selinux_init(void)
7394 {
7395 pr_info("SELinux: Initializing.\n");
7396
7397 memset(&selinux_state, 0, sizeof(selinux_state));
7398 enforcing_set(&selinux_state, selinux_enforcing_boot);
7399 checkreqprot_set(&selinux_state, selinux_checkreqprot_boot);
7400 selinux_avc_init(&selinux_state.avc);
7401 mutex_init(&selinux_state.status_lock);
7402 mutex_init(&selinux_state.policy_mutex);
7403
7404 /* Set the security state for the initial task. */
7405 cred_init_security();
7406
7407 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7408
7409 avc_init();
7410
7411 avtab_cache_init();
7412
7413 ebitmap_cache_init();
7414
7415 hashtab_cache_init();
7416
7417 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7418 &selinux_lsmid);
7419
7420 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7421 panic("SELinux: Unable to register AVC netcache callback\n");
7422
7423 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7424 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7425
7426 if (selinux_enforcing_boot)
7427 pr_debug("SELinux: Starting in enforcing mode\n");
7428 else
7429 pr_debug("SELinux: Starting in permissive mode\n");
7430
7431 fs_validate_description("selinux", selinux_fs_parameters);
7432
7433 return 0;
7434 }
7435
7436 static void delayed_superblock_init(struct super_block *sb, void *unused)
7437 {
7438 selinux_set_mnt_opts(sb, NULL, 0, NULL);
7439 }
7440
7441 void selinux_complete_init(void)
7442 {
7443 pr_debug("SELinux: Completing initialization.\n");
7444
7445 /* Set up any superblocks initialized prior to the policy load. */
7446 pr_debug("SELinux: Setting up existing superblocks.\n");
7447 iterate_supers(delayed_superblock_init, NULL);
7448 }
7449
7450 /* SELinux requires early initialization in order to label
7451 all processes and objects when they are created. */
7452 DEFINE_LSM(selinux) = {
7453 .name = "selinux",
7454 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7455 .enabled = &selinux_enabled_boot,
7456 .blobs = &selinux_blob_sizes,
7457 .init = selinux_init,
7458 };
7459
7460 #if defined(CONFIG_NETFILTER)
7461
7462 static const struct nf_hook_ops selinux_nf_ops[] = {
7463 {
7464 .hook = selinux_ipv4_postroute,
7465 .pf = NFPROTO_IPV4,
7466 .hooknum = NF_INET_POST_ROUTING,
7467 .priority = NF_IP_PRI_SELINUX_LAST,
7468 },
7469 {
7470 .hook = selinux_ipv4_forward,
7471 .pf = NFPROTO_IPV4,
7472 .hooknum = NF_INET_FORWARD,
7473 .priority = NF_IP_PRI_SELINUX_FIRST,
7474 },
7475 {
7476 .hook = selinux_ipv4_output,
7477 .pf = NFPROTO_IPV4,
7478 .hooknum = NF_INET_LOCAL_OUT,
7479 .priority = NF_IP_PRI_SELINUX_FIRST,
7480 },
7481 #if IS_ENABLED(CONFIG_IPV6)
7482 {
7483 .hook = selinux_ipv6_postroute,
7484 .pf = NFPROTO_IPV6,
7485 .hooknum = NF_INET_POST_ROUTING,
7486 .priority = NF_IP6_PRI_SELINUX_LAST,
7487 },
7488 {
7489 .hook = selinux_ipv6_forward,
7490 .pf = NFPROTO_IPV6,
7491 .hooknum = NF_INET_FORWARD,
7492 .priority = NF_IP6_PRI_SELINUX_FIRST,
7493 },
7494 {
7495 .hook = selinux_ipv6_output,
7496 .pf = NFPROTO_IPV6,
7497 .hooknum = NF_INET_LOCAL_OUT,
7498 .priority = NF_IP6_PRI_SELINUX_FIRST,
7499 },
7500 #endif /* IPV6 */
7501 };
7502
7503 static int __net_init selinux_nf_register(struct net *net)
7504 {
7505 return nf_register_net_hooks(net, selinux_nf_ops,
7506 ARRAY_SIZE(selinux_nf_ops));
7507 }
7508
7509 static void __net_exit selinux_nf_unregister(struct net *net)
7510 {
7511 nf_unregister_net_hooks(net, selinux_nf_ops,
7512 ARRAY_SIZE(selinux_nf_ops));
7513 }
7514
7515 static struct pernet_operations selinux_net_ops = {
7516 .init = selinux_nf_register,
7517 .exit = selinux_nf_unregister,
7518 };
7519
7520 static int __init selinux_nf_ip_init(void)
7521 {
7522 int err;
7523
7524 if (!selinux_enabled_boot)
7525 return 0;
7526
7527 pr_debug("SELinux: Registering netfilter hooks\n");
7528
7529 err = register_pernet_subsys(&selinux_net_ops);
7530 if (err)
7531 panic("SELinux: register_pernet_subsys: error %d\n", err);
7532
7533 return 0;
7534 }
7535 __initcall(selinux_nf_ip_init);
7536
7537 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7538 static void selinux_nf_ip_exit(void)
7539 {
7540 pr_debug("SELinux: Unregistering netfilter hooks\n");
7541
7542 unregister_pernet_subsys(&selinux_net_ops);
7543 }
7544 #endif
7545
7546 #else /* CONFIG_NETFILTER */
7547
7548 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7549 #define selinux_nf_ip_exit()
7550 #endif
7551
7552 #endif /* CONFIG_NETFILTER */
7553
7554 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7555 int selinux_disable(struct selinux_state *state)
7556 {
7557 if (selinux_initialized(state)) {
7558 /* Not permitted after initial policy load. */
7559 return -EINVAL;
7560 }
7561
7562 if (selinux_disabled(state)) {
7563 /* Only do this once. */
7564 return -EINVAL;
7565 }
7566
7567 selinux_mark_disabled(state);
7568
7569 pr_info("SELinux: Disabled at runtime.\n");
7570
7571 /*
7572 * Unregister netfilter hooks.
7573 * Must be done before security_delete_hooks() to avoid breaking
7574 * runtime disable.
7575 */
7576 selinux_nf_ip_exit();
7577
7578 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7579
7580 /* Try to destroy the avc node cache */
7581 avc_disable();
7582
7583 /* Unregister selinuxfs. */
7584 exit_sel_fs();
7585
7586 return 0;
7587 }
7588 #endif
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