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