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1 /* auditfilter.c -- filtering of audit events
2 *
3 * Copyright 2003-2004 Red Hat, Inc.
4 * Copyright 2005 Hewlett-Packard Development Company, L.P.
5 * Copyright 2005 IBM Corporation
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23
24 #include <linux/kernel.h>
25 #include <linux/audit.h>
26 #include <linux/kthread.h>
27 #include <linux/mutex.h>
28 #include <linux/fs.h>
29 #include <linux/namei.h>
30 #include <linux/netlink.h>
31 #include <linux/sched.h>
32 #include <linux/slab.h>
33 #include <linux/security.h>
34 #include <net/net_namespace.h>
35 #include <net/sock.h>
36 #include "audit.h"
37
38 /*
39 * Locking model:
40 *
41 * audit_filter_mutex:
42 * Synchronizes writes and blocking reads of audit's filterlist
43 * data. Rcu is used to traverse the filterlist and access
44 * contents of structs audit_entry, audit_watch and opaque
45 * LSM rules during filtering. If modified, these structures
46 * must be copied and replace their counterparts in the filterlist.
47 * An audit_parent struct is not accessed during filtering, so may
48 * be written directly provided audit_filter_mutex is held.
49 */
50
51 /* Audit filter lists, defined in <linux/audit.h> */
52 struct list_head audit_filter_list[AUDIT_NR_FILTERS] = {
53 LIST_HEAD_INIT(audit_filter_list[0]),
54 LIST_HEAD_INIT(audit_filter_list[1]),
55 LIST_HEAD_INIT(audit_filter_list[2]),
56 LIST_HEAD_INIT(audit_filter_list[3]),
57 LIST_HEAD_INIT(audit_filter_list[4]),
58 LIST_HEAD_INIT(audit_filter_list[5]),
59 LIST_HEAD_INIT(audit_filter_list[6]),
60 #if AUDIT_NR_FILTERS != 7
61 #error Fix audit_filter_list initialiser
62 #endif
63 };
64 static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = {
65 LIST_HEAD_INIT(audit_rules_list[0]),
66 LIST_HEAD_INIT(audit_rules_list[1]),
67 LIST_HEAD_INIT(audit_rules_list[2]),
68 LIST_HEAD_INIT(audit_rules_list[3]),
69 LIST_HEAD_INIT(audit_rules_list[4]),
70 LIST_HEAD_INIT(audit_rules_list[5]),
71 LIST_HEAD_INIT(audit_rules_list[6]),
72 };
73
74 DEFINE_MUTEX(audit_filter_mutex);
75
76 static void audit_free_lsm_field(struct audit_field *f)
77 {
78 switch (f->type) {
79 case AUDIT_SUBJ_USER:
80 case AUDIT_SUBJ_ROLE:
81 case AUDIT_SUBJ_TYPE:
82 case AUDIT_SUBJ_SEN:
83 case AUDIT_SUBJ_CLR:
84 case AUDIT_OBJ_USER:
85 case AUDIT_OBJ_ROLE:
86 case AUDIT_OBJ_TYPE:
87 case AUDIT_OBJ_LEV_LOW:
88 case AUDIT_OBJ_LEV_HIGH:
89 kfree(f->lsm_str);
90 security_audit_rule_free(f->lsm_rule);
91 }
92 }
93
94 static inline void audit_free_rule(struct audit_entry *e)
95 {
96 int i;
97 struct audit_krule *erule = &e->rule;
98
99 /* some rules don't have associated watches */
100 if (erule->watch)
101 audit_put_watch(erule->watch);
102 if (erule->fields)
103 for (i = 0; i < erule->field_count; i++)
104 audit_free_lsm_field(&erule->fields[i]);
105 kfree(erule->fields);
106 kfree(erule->filterkey);
107 kfree(e);
108 }
109
110 void audit_free_rule_rcu(struct rcu_head *head)
111 {
112 struct audit_entry *e = container_of(head, struct audit_entry, rcu);
113 audit_free_rule(e);
114 }
115
116 /* Initialize an audit filterlist entry. */
117 static inline struct audit_entry *audit_init_entry(u32 field_count)
118 {
119 struct audit_entry *entry;
120 struct audit_field *fields;
121
122 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
123 if (unlikely(!entry))
124 return NULL;
125
126 fields = kcalloc(field_count, sizeof(*fields), GFP_KERNEL);
127 if (unlikely(!fields)) {
128 kfree(entry);
129 return NULL;
130 }
131 entry->rule.fields = fields;
132
133 return entry;
134 }
135
136 /* Unpack a filter field's string representation from user-space
137 * buffer. */
138 char *audit_unpack_string(void **bufp, size_t *remain, size_t len)
139 {
140 char *str;
141
142 if (!*bufp || (len == 0) || (len > *remain))
143 return ERR_PTR(-EINVAL);
144
145 /* Of the currently implemented string fields, PATH_MAX
146 * defines the longest valid length.
147 */
148 if (len > PATH_MAX)
149 return ERR_PTR(-ENAMETOOLONG);
150
151 str = kmalloc(len + 1, GFP_KERNEL);
152 if (unlikely(!str))
153 return ERR_PTR(-ENOMEM);
154
155 memcpy(str, *bufp, len);
156 str[len] = 0;
157 *bufp += len;
158 *remain -= len;
159
160 return str;
161 }
162
163 /* Translate an inode field to kernel representation. */
164 static inline int audit_to_inode(struct audit_krule *krule,
165 struct audit_field *f)
166 {
167 if (krule->listnr != AUDIT_FILTER_EXIT ||
168 krule->inode_f || krule->watch || krule->tree ||
169 (f->op != Audit_equal && f->op != Audit_not_equal))
170 return -EINVAL;
171
172 krule->inode_f = f;
173 return 0;
174 }
175
176 static __u32 *classes[AUDIT_SYSCALL_CLASSES];
177
178 int __init audit_register_class(int class, unsigned *list)
179 {
180 __u32 *p = kcalloc(AUDIT_BITMASK_SIZE, sizeof(__u32), GFP_KERNEL);
181 if (!p)
182 return -ENOMEM;
183 while (*list != ~0U) {
184 unsigned n = *list++;
185 if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) {
186 kfree(p);
187 return -EINVAL;
188 }
189 p[AUDIT_WORD(n)] |= AUDIT_BIT(n);
190 }
191 if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) {
192 kfree(p);
193 return -EINVAL;
194 }
195 classes[class] = p;
196 return 0;
197 }
198
199 int audit_match_class(int class, unsigned syscall)
200 {
201 if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32))
202 return 0;
203 if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class]))
204 return 0;
205 return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall);
206 }
207
208 #ifdef CONFIG_AUDITSYSCALL
209 static inline int audit_match_class_bits(int class, u32 *mask)
210 {
211 int i;
212
213 if (classes[class]) {
214 for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
215 if (mask[i] & classes[class][i])
216 return 0;
217 }
218 return 1;
219 }
220
221 static int audit_match_signal(struct audit_entry *entry)
222 {
223 struct audit_field *arch = entry->rule.arch_f;
224
225 if (!arch) {
226 /* When arch is unspecified, we must check both masks on biarch
227 * as syscall number alone is ambiguous. */
228 return (audit_match_class_bits(AUDIT_CLASS_SIGNAL,
229 entry->rule.mask) &&
230 audit_match_class_bits(AUDIT_CLASS_SIGNAL_32,
231 entry->rule.mask));
232 }
233
234 switch(audit_classify_arch(arch->val)) {
235 case 0: /* native */
236 return (audit_match_class_bits(AUDIT_CLASS_SIGNAL,
237 entry->rule.mask));
238 case 1: /* 32bit on biarch */
239 return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32,
240 entry->rule.mask));
241 default:
242 return 1;
243 }
244 }
245 #endif
246
247 /* Common user-space to kernel rule translation. */
248 static inline struct audit_entry *audit_to_entry_common(struct audit_rule_data *rule)
249 {
250 unsigned listnr;
251 struct audit_entry *entry;
252 int i, err;
253
254 err = -EINVAL;
255 listnr = rule->flags & ~AUDIT_FILTER_PREPEND;
256 switch(listnr) {
257 default:
258 goto exit_err;
259 #ifdef CONFIG_AUDITSYSCALL
260 case AUDIT_FILTER_ENTRY:
261 if (rule->action == AUDIT_ALWAYS)
262 goto exit_err;
263 case AUDIT_FILTER_EXIT:
264 case AUDIT_FILTER_TASK:
265 #endif
266 case AUDIT_FILTER_USER:
267 case AUDIT_FILTER_TYPE:
268 case AUDIT_FILTER_FS:
269 ;
270 }
271 if (unlikely(rule->action == AUDIT_POSSIBLE)) {
272 pr_err("AUDIT_POSSIBLE is deprecated\n");
273 goto exit_err;
274 }
275 if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS)
276 goto exit_err;
277 if (rule->field_count > AUDIT_MAX_FIELDS)
278 goto exit_err;
279
280 err = -ENOMEM;
281 entry = audit_init_entry(rule->field_count);
282 if (!entry)
283 goto exit_err;
284
285 entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND;
286 entry->rule.listnr = listnr;
287 entry->rule.action = rule->action;
288 entry->rule.field_count = rule->field_count;
289
290 for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
291 entry->rule.mask[i] = rule->mask[i];
292
293 for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) {
294 int bit = AUDIT_BITMASK_SIZE * 32 - i - 1;
295 __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)];
296 __u32 *class;
297
298 if (!(*p & AUDIT_BIT(bit)))
299 continue;
300 *p &= ~AUDIT_BIT(bit);
301 class = classes[i];
302 if (class) {
303 int j;
304 for (j = 0; j < AUDIT_BITMASK_SIZE; j++)
305 entry->rule.mask[j] |= class[j];
306 }
307 }
308
309 return entry;
310
311 exit_err:
312 return ERR_PTR(err);
313 }
314
315 static u32 audit_ops[] =
316 {
317 [Audit_equal] = AUDIT_EQUAL,
318 [Audit_not_equal] = AUDIT_NOT_EQUAL,
319 [Audit_bitmask] = AUDIT_BIT_MASK,
320 [Audit_bittest] = AUDIT_BIT_TEST,
321 [Audit_lt] = AUDIT_LESS_THAN,
322 [Audit_gt] = AUDIT_GREATER_THAN,
323 [Audit_le] = AUDIT_LESS_THAN_OR_EQUAL,
324 [Audit_ge] = AUDIT_GREATER_THAN_OR_EQUAL,
325 };
326
327 static u32 audit_to_op(u32 op)
328 {
329 u32 n;
330 for (n = Audit_equal; n < Audit_bad && audit_ops[n] != op; n++)
331 ;
332 return n;
333 }
334
335 /* check if an audit field is valid */
336 static int audit_field_valid(struct audit_entry *entry, struct audit_field *f)
337 {
338 switch(f->type) {
339 case AUDIT_MSGTYPE:
340 if (entry->rule.listnr != AUDIT_FILTER_TYPE &&
341 entry->rule.listnr != AUDIT_FILTER_USER)
342 return -EINVAL;
343 break;
344 case AUDIT_FSTYPE:
345 if (entry->rule.listnr != AUDIT_FILTER_FS)
346 return -EINVAL;
347 break;
348 }
349
350 switch(entry->rule.listnr) {
351 case AUDIT_FILTER_FS:
352 switch(f->type) {
353 case AUDIT_FSTYPE:
354 case AUDIT_FILTERKEY:
355 break;
356 default:
357 return -EINVAL;
358 }
359 }
360
361 switch(f->type) {
362 default:
363 return -EINVAL;
364 case AUDIT_UID:
365 case AUDIT_EUID:
366 case AUDIT_SUID:
367 case AUDIT_FSUID:
368 case AUDIT_LOGINUID:
369 case AUDIT_OBJ_UID:
370 case AUDIT_GID:
371 case AUDIT_EGID:
372 case AUDIT_SGID:
373 case AUDIT_FSGID:
374 case AUDIT_OBJ_GID:
375 case AUDIT_PID:
376 case AUDIT_PERS:
377 case AUDIT_MSGTYPE:
378 case AUDIT_PPID:
379 case AUDIT_DEVMAJOR:
380 case AUDIT_DEVMINOR:
381 case AUDIT_EXIT:
382 case AUDIT_SUCCESS:
383 case AUDIT_INODE:
384 case AUDIT_SESSIONID:
385 /* bit ops are only useful on syscall args */
386 if (f->op == Audit_bitmask || f->op == Audit_bittest)
387 return -EINVAL;
388 break;
389 case AUDIT_ARG0:
390 case AUDIT_ARG1:
391 case AUDIT_ARG2:
392 case AUDIT_ARG3:
393 case AUDIT_SUBJ_USER:
394 case AUDIT_SUBJ_ROLE:
395 case AUDIT_SUBJ_TYPE:
396 case AUDIT_SUBJ_SEN:
397 case AUDIT_SUBJ_CLR:
398 case AUDIT_OBJ_USER:
399 case AUDIT_OBJ_ROLE:
400 case AUDIT_OBJ_TYPE:
401 case AUDIT_OBJ_LEV_LOW:
402 case AUDIT_OBJ_LEV_HIGH:
403 case AUDIT_WATCH:
404 case AUDIT_DIR:
405 case AUDIT_FILTERKEY:
406 break;
407 case AUDIT_LOGINUID_SET:
408 if ((f->val != 0) && (f->val != 1))
409 return -EINVAL;
410 /* FALL THROUGH */
411 case AUDIT_ARCH:
412 case AUDIT_FSTYPE:
413 if (f->op != Audit_not_equal && f->op != Audit_equal)
414 return -EINVAL;
415 break;
416 case AUDIT_PERM:
417 if (f->val & ~15)
418 return -EINVAL;
419 break;
420 case AUDIT_FILETYPE:
421 if (f->val & ~S_IFMT)
422 return -EINVAL;
423 break;
424 case AUDIT_FIELD_COMPARE:
425 if (f->val > AUDIT_MAX_FIELD_COMPARE)
426 return -EINVAL;
427 break;
428 case AUDIT_EXE:
429 if (f->op != Audit_not_equal && f->op != Audit_equal)
430 return -EINVAL;
431 if (entry->rule.listnr != AUDIT_FILTER_EXIT)
432 return -EINVAL;
433 break;
434 }
435 return 0;
436 }
437
438 /* Translate struct audit_rule_data to kernel's rule representation. */
439 static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
440 size_t datasz)
441 {
442 int err = 0;
443 struct audit_entry *entry;
444 void *bufp;
445 size_t remain = datasz - sizeof(struct audit_rule_data);
446 int i;
447 char *str;
448 struct audit_fsnotify_mark *audit_mark;
449
450 entry = audit_to_entry_common(data);
451 if (IS_ERR(entry))
452 goto exit_nofree;
453
454 bufp = data->buf;
455 for (i = 0; i < data->field_count; i++) {
456 struct audit_field *f = &entry->rule.fields[i];
457
458 err = -EINVAL;
459
460 f->op = audit_to_op(data->fieldflags[i]);
461 if (f->op == Audit_bad)
462 goto exit_free;
463
464 f->type = data->fields[i];
465 f->val = data->values[i];
466
467 /* Support legacy tests for a valid loginuid */
468 if ((f->type == AUDIT_LOGINUID) && (f->val == AUDIT_UID_UNSET)) {
469 f->type = AUDIT_LOGINUID_SET;
470 f->val = 0;
471 entry->rule.pflags |= AUDIT_LOGINUID_LEGACY;
472 }
473
474 err = audit_field_valid(entry, f);
475 if (err)
476 goto exit_free;
477
478 err = -EINVAL;
479 switch (f->type) {
480 case AUDIT_LOGINUID:
481 case AUDIT_UID:
482 case AUDIT_EUID:
483 case AUDIT_SUID:
484 case AUDIT_FSUID:
485 case AUDIT_OBJ_UID:
486 f->uid = make_kuid(current_user_ns(), f->val);
487 if (!uid_valid(f->uid))
488 goto exit_free;
489 break;
490 case AUDIT_GID:
491 case AUDIT_EGID:
492 case AUDIT_SGID:
493 case AUDIT_FSGID:
494 case AUDIT_OBJ_GID:
495 f->gid = make_kgid(current_user_ns(), f->val);
496 if (!gid_valid(f->gid))
497 goto exit_free;
498 break;
499 case AUDIT_SESSIONID:
500 case AUDIT_ARCH:
501 entry->rule.arch_f = f;
502 break;
503 case AUDIT_SUBJ_USER:
504 case AUDIT_SUBJ_ROLE:
505 case AUDIT_SUBJ_TYPE:
506 case AUDIT_SUBJ_SEN:
507 case AUDIT_SUBJ_CLR:
508 case AUDIT_OBJ_USER:
509 case AUDIT_OBJ_ROLE:
510 case AUDIT_OBJ_TYPE:
511 case AUDIT_OBJ_LEV_LOW:
512 case AUDIT_OBJ_LEV_HIGH:
513 str = audit_unpack_string(&bufp, &remain, f->val);
514 if (IS_ERR(str))
515 goto exit_free;
516 entry->rule.buflen += f->val;
517
518 err = security_audit_rule_init(f->type, f->op, str,
519 (void **)&f->lsm_rule);
520 /* Keep currently invalid fields around in case they
521 * become valid after a policy reload. */
522 if (err == -EINVAL) {
523 pr_warn("audit rule for LSM \'%s\' is invalid\n",
524 str);
525 err = 0;
526 }
527 if (err) {
528 kfree(str);
529 goto exit_free;
530 } else
531 f->lsm_str = str;
532 break;
533 case AUDIT_WATCH:
534 str = audit_unpack_string(&bufp, &remain, f->val);
535 if (IS_ERR(str))
536 goto exit_free;
537 entry->rule.buflen += f->val;
538
539 err = audit_to_watch(&entry->rule, str, f->val, f->op);
540 if (err) {
541 kfree(str);
542 goto exit_free;
543 }
544 break;
545 case AUDIT_DIR:
546 str = audit_unpack_string(&bufp, &remain, f->val);
547 if (IS_ERR(str))
548 goto exit_free;
549 entry->rule.buflen += f->val;
550
551 err = audit_make_tree(&entry->rule, str, f->op);
552 kfree(str);
553 if (err)
554 goto exit_free;
555 break;
556 case AUDIT_INODE:
557 err = audit_to_inode(&entry->rule, f);
558 if (err)
559 goto exit_free;
560 break;
561 case AUDIT_FILTERKEY:
562 if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN)
563 goto exit_free;
564 str = audit_unpack_string(&bufp, &remain, f->val);
565 if (IS_ERR(str))
566 goto exit_free;
567 entry->rule.buflen += f->val;
568 entry->rule.filterkey = str;
569 break;
570 case AUDIT_EXE:
571 if (entry->rule.exe || f->val > PATH_MAX)
572 goto exit_free;
573 str = audit_unpack_string(&bufp, &remain, f->val);
574 if (IS_ERR(str)) {
575 err = PTR_ERR(str);
576 goto exit_free;
577 }
578 entry->rule.buflen += f->val;
579
580 audit_mark = audit_alloc_mark(&entry->rule, str, f->val);
581 if (IS_ERR(audit_mark)) {
582 kfree(str);
583 err = PTR_ERR(audit_mark);
584 goto exit_free;
585 }
586 entry->rule.exe = audit_mark;
587 break;
588 }
589 }
590
591 if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal)
592 entry->rule.inode_f = NULL;
593
594 exit_nofree:
595 return entry;
596
597 exit_free:
598 if (entry->rule.tree)
599 audit_put_tree(entry->rule.tree); /* that's the temporary one */
600 if (entry->rule.exe)
601 audit_remove_mark(entry->rule.exe); /* that's the template one */
602 audit_free_rule(entry);
603 return ERR_PTR(err);
604 }
605
606 /* Pack a filter field's string representation into data block. */
607 static inline size_t audit_pack_string(void **bufp, const char *str)
608 {
609 size_t len = strlen(str);
610
611 memcpy(*bufp, str, len);
612 *bufp += len;
613
614 return len;
615 }
616
617 /* Translate kernel rule representation to struct audit_rule_data. */
618 static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule)
619 {
620 struct audit_rule_data *data;
621 void *bufp;
622 int i;
623
624 data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL);
625 if (unlikely(!data))
626 return NULL;
627 memset(data, 0, sizeof(*data));
628
629 data->flags = krule->flags | krule->listnr;
630 data->action = krule->action;
631 data->field_count = krule->field_count;
632 bufp = data->buf;
633 for (i = 0; i < data->field_count; i++) {
634 struct audit_field *f = &krule->fields[i];
635
636 data->fields[i] = f->type;
637 data->fieldflags[i] = audit_ops[f->op];
638 switch(f->type) {
639 case AUDIT_SUBJ_USER:
640 case AUDIT_SUBJ_ROLE:
641 case AUDIT_SUBJ_TYPE:
642 case AUDIT_SUBJ_SEN:
643 case AUDIT_SUBJ_CLR:
644 case AUDIT_OBJ_USER:
645 case AUDIT_OBJ_ROLE:
646 case AUDIT_OBJ_TYPE:
647 case AUDIT_OBJ_LEV_LOW:
648 case AUDIT_OBJ_LEV_HIGH:
649 data->buflen += data->values[i] =
650 audit_pack_string(&bufp, f->lsm_str);
651 break;
652 case AUDIT_WATCH:
653 data->buflen += data->values[i] =
654 audit_pack_string(&bufp,
655 audit_watch_path(krule->watch));
656 break;
657 case AUDIT_DIR:
658 data->buflen += data->values[i] =
659 audit_pack_string(&bufp,
660 audit_tree_path(krule->tree));
661 break;
662 case AUDIT_FILTERKEY:
663 data->buflen += data->values[i] =
664 audit_pack_string(&bufp, krule->filterkey);
665 break;
666 case AUDIT_EXE:
667 data->buflen += data->values[i] =
668 audit_pack_string(&bufp, audit_mark_path(krule->exe));
669 break;
670 case AUDIT_LOGINUID_SET:
671 if (krule->pflags & AUDIT_LOGINUID_LEGACY && !f->val) {
672 data->fields[i] = AUDIT_LOGINUID;
673 data->values[i] = AUDIT_UID_UNSET;
674 break;
675 }
676 /* fallthrough if set */
677 default:
678 data->values[i] = f->val;
679 }
680 }
681 for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i];
682
683 return data;
684 }
685
686 /* Compare two rules in kernel format. Considered success if rules
687 * don't match. */
688 static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b)
689 {
690 int i;
691
692 if (a->flags != b->flags ||
693 a->pflags != b->pflags ||
694 a->listnr != b->listnr ||
695 a->action != b->action ||
696 a->field_count != b->field_count)
697 return 1;
698
699 for (i = 0; i < a->field_count; i++) {
700 if (a->fields[i].type != b->fields[i].type ||
701 a->fields[i].op != b->fields[i].op)
702 return 1;
703
704 switch(a->fields[i].type) {
705 case AUDIT_SUBJ_USER:
706 case AUDIT_SUBJ_ROLE:
707 case AUDIT_SUBJ_TYPE:
708 case AUDIT_SUBJ_SEN:
709 case AUDIT_SUBJ_CLR:
710 case AUDIT_OBJ_USER:
711 case AUDIT_OBJ_ROLE:
712 case AUDIT_OBJ_TYPE:
713 case AUDIT_OBJ_LEV_LOW:
714 case AUDIT_OBJ_LEV_HIGH:
715 if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str))
716 return 1;
717 break;
718 case AUDIT_WATCH:
719 if (strcmp(audit_watch_path(a->watch),
720 audit_watch_path(b->watch)))
721 return 1;
722 break;
723 case AUDIT_DIR:
724 if (strcmp(audit_tree_path(a->tree),
725 audit_tree_path(b->tree)))
726 return 1;
727 break;
728 case AUDIT_FILTERKEY:
729 /* both filterkeys exist based on above type compare */
730 if (strcmp(a->filterkey, b->filterkey))
731 return 1;
732 break;
733 case AUDIT_EXE:
734 /* both paths exist based on above type compare */
735 if (strcmp(audit_mark_path(a->exe),
736 audit_mark_path(b->exe)))
737 return 1;
738 break;
739 case AUDIT_UID:
740 case AUDIT_EUID:
741 case AUDIT_SUID:
742 case AUDIT_FSUID:
743 case AUDIT_LOGINUID:
744 case AUDIT_OBJ_UID:
745 if (!uid_eq(a->fields[i].uid, b->fields[i].uid))
746 return 1;
747 break;
748 case AUDIT_GID:
749 case AUDIT_EGID:
750 case AUDIT_SGID:
751 case AUDIT_FSGID:
752 case AUDIT_OBJ_GID:
753 if (!gid_eq(a->fields[i].gid, b->fields[i].gid))
754 return 1;
755 break;
756 default:
757 if (a->fields[i].val != b->fields[i].val)
758 return 1;
759 }
760 }
761
762 for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
763 if (a->mask[i] != b->mask[i])
764 return 1;
765
766 return 0;
767 }
768
769 /* Duplicate LSM field information. The lsm_rule is opaque, so must be
770 * re-initialized. */
771 static inline int audit_dupe_lsm_field(struct audit_field *df,
772 struct audit_field *sf)
773 {
774 int ret = 0;
775 char *lsm_str;
776
777 /* our own copy of lsm_str */
778 lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL);
779 if (unlikely(!lsm_str))
780 return -ENOMEM;
781 df->lsm_str = lsm_str;
782
783 /* our own (refreshed) copy of lsm_rule */
784 ret = security_audit_rule_init(df->type, df->op, df->lsm_str,
785 (void **)&df->lsm_rule);
786 /* Keep currently invalid fields around in case they
787 * become valid after a policy reload. */
788 if (ret == -EINVAL) {
789 pr_warn("audit rule for LSM \'%s\' is invalid\n",
790 df->lsm_str);
791 ret = 0;
792 }
793
794 return ret;
795 }
796
797 /* Duplicate an audit rule. This will be a deep copy with the exception
798 * of the watch - that pointer is carried over. The LSM specific fields
799 * will be updated in the copy. The point is to be able to replace the old
800 * rule with the new rule in the filterlist, then free the old rule.
801 * The rlist element is undefined; list manipulations are handled apart from
802 * the initial copy. */
803 struct audit_entry *audit_dupe_rule(struct audit_krule *old)
804 {
805 u32 fcount = old->field_count;
806 struct audit_entry *entry;
807 struct audit_krule *new;
808 char *fk;
809 int i, err = 0;
810
811 entry = audit_init_entry(fcount);
812 if (unlikely(!entry))
813 return ERR_PTR(-ENOMEM);
814
815 new = &entry->rule;
816 new->flags = old->flags;
817 new->pflags = old->pflags;
818 new->listnr = old->listnr;
819 new->action = old->action;
820 for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
821 new->mask[i] = old->mask[i];
822 new->prio = old->prio;
823 new->buflen = old->buflen;
824 new->inode_f = old->inode_f;
825 new->field_count = old->field_count;
826
827 /*
828 * note that we are OK with not refcounting here; audit_match_tree()
829 * never dereferences tree and we can't get false positives there
830 * since we'd have to have rule gone from the list *and* removed
831 * before the chunks found by lookup had been allocated, i.e. before
832 * the beginning of list scan.
833 */
834 new->tree = old->tree;
835 memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount);
836
837 /* deep copy this information, updating the lsm_rule fields, because
838 * the originals will all be freed when the old rule is freed. */
839 for (i = 0; i < fcount; i++) {
840 switch (new->fields[i].type) {
841 case AUDIT_SUBJ_USER:
842 case AUDIT_SUBJ_ROLE:
843 case AUDIT_SUBJ_TYPE:
844 case AUDIT_SUBJ_SEN:
845 case AUDIT_SUBJ_CLR:
846 case AUDIT_OBJ_USER:
847 case AUDIT_OBJ_ROLE:
848 case AUDIT_OBJ_TYPE:
849 case AUDIT_OBJ_LEV_LOW:
850 case AUDIT_OBJ_LEV_HIGH:
851 err = audit_dupe_lsm_field(&new->fields[i],
852 &old->fields[i]);
853 break;
854 case AUDIT_FILTERKEY:
855 fk = kstrdup(old->filterkey, GFP_KERNEL);
856 if (unlikely(!fk))
857 err = -ENOMEM;
858 else
859 new->filterkey = fk;
860 break;
861 case AUDIT_EXE:
862 err = audit_dupe_exe(new, old);
863 break;
864 }
865 if (err) {
866 if (new->exe)
867 audit_remove_mark(new->exe);
868 audit_free_rule(entry);
869 return ERR_PTR(err);
870 }
871 }
872
873 if (old->watch) {
874 audit_get_watch(old->watch);
875 new->watch = old->watch;
876 }
877
878 return entry;
879 }
880
881 /* Find an existing audit rule.
882 * Caller must hold audit_filter_mutex to prevent stale rule data. */
883 static struct audit_entry *audit_find_rule(struct audit_entry *entry,
884 struct list_head **p)
885 {
886 struct audit_entry *e, *found = NULL;
887 struct list_head *list;
888 int h;
889
890 if (entry->rule.inode_f) {
891 h = audit_hash_ino(entry->rule.inode_f->val);
892 *p = list = &audit_inode_hash[h];
893 } else if (entry->rule.watch) {
894 /* we don't know the inode number, so must walk entire hash */
895 for (h = 0; h < AUDIT_INODE_BUCKETS; h++) {
896 list = &audit_inode_hash[h];
897 list_for_each_entry(e, list, list)
898 if (!audit_compare_rule(&entry->rule, &e->rule)) {
899 found = e;
900 goto out;
901 }
902 }
903 goto out;
904 } else {
905 *p = list = &audit_filter_list[entry->rule.listnr];
906 }
907
908 list_for_each_entry(e, list, list)
909 if (!audit_compare_rule(&entry->rule, &e->rule)) {
910 found = e;
911 goto out;
912 }
913
914 out:
915 return found;
916 }
917
918 static u64 prio_low = ~0ULL/2;
919 static u64 prio_high = ~0ULL/2 - 1;
920
921 /* Add rule to given filterlist if not a duplicate. */
922 static inline int audit_add_rule(struct audit_entry *entry)
923 {
924 struct audit_entry *e;
925 struct audit_watch *watch = entry->rule.watch;
926 struct audit_tree *tree = entry->rule.tree;
927 struct list_head *list;
928 int err = 0;
929 #ifdef CONFIG_AUDITSYSCALL
930 int dont_count = 0;
931
932 /* If any of these, don't count towards total */
933 switch(entry->rule.listnr) {
934 case AUDIT_FILTER_USER:
935 case AUDIT_FILTER_TYPE:
936 case AUDIT_FILTER_FS:
937 dont_count = 1;
938 }
939 #endif
940
941 mutex_lock(&audit_filter_mutex);
942 e = audit_find_rule(entry, &list);
943 if (e) {
944 mutex_unlock(&audit_filter_mutex);
945 err = -EEXIST;
946 /* normally audit_add_tree_rule() will free it on failure */
947 if (tree)
948 audit_put_tree(tree);
949 return err;
950 }
951
952 if (watch) {
953 /* audit_filter_mutex is dropped and re-taken during this call */
954 err = audit_add_watch(&entry->rule, &list);
955 if (err) {
956 mutex_unlock(&audit_filter_mutex);
957 /*
958 * normally audit_add_tree_rule() will free it
959 * on failure
960 */
961 if (tree)
962 audit_put_tree(tree);
963 return err;
964 }
965 }
966 if (tree) {
967 err = audit_add_tree_rule(&entry->rule);
968 if (err) {
969 mutex_unlock(&audit_filter_mutex);
970 return err;
971 }
972 }
973
974 entry->rule.prio = ~0ULL;
975 if (entry->rule.listnr == AUDIT_FILTER_EXIT) {
976 if (entry->rule.flags & AUDIT_FILTER_PREPEND)
977 entry->rule.prio = ++prio_high;
978 else
979 entry->rule.prio = --prio_low;
980 }
981
982 if (entry->rule.flags & AUDIT_FILTER_PREPEND) {
983 list_add(&entry->rule.list,
984 &audit_rules_list[entry->rule.listnr]);
985 list_add_rcu(&entry->list, list);
986 entry->rule.flags &= ~AUDIT_FILTER_PREPEND;
987 } else {
988 list_add_tail(&entry->rule.list,
989 &audit_rules_list[entry->rule.listnr]);
990 list_add_tail_rcu(&entry->list, list);
991 }
992 #ifdef CONFIG_AUDITSYSCALL
993 if (!dont_count)
994 audit_n_rules++;
995
996 if (!audit_match_signal(entry))
997 audit_signals++;
998 #endif
999 mutex_unlock(&audit_filter_mutex);
1000
1001 return err;
1002 }
1003
1004 /* Remove an existing rule from filterlist. */
1005 int audit_del_rule(struct audit_entry *entry)
1006 {
1007 struct audit_entry *e;
1008 struct audit_tree *tree = entry->rule.tree;
1009 struct list_head *list;
1010 int ret = 0;
1011 #ifdef CONFIG_AUDITSYSCALL
1012 int dont_count = 0;
1013
1014 /* If any of these, don't count towards total */
1015 switch(entry->rule.listnr) {
1016 case AUDIT_FILTER_USER:
1017 case AUDIT_FILTER_TYPE:
1018 case AUDIT_FILTER_FS:
1019 dont_count = 1;
1020 }
1021 #endif
1022
1023 mutex_lock(&audit_filter_mutex);
1024 e = audit_find_rule(entry, &list);
1025 if (!e) {
1026 ret = -ENOENT;
1027 goto out;
1028 }
1029
1030 if (e->rule.watch)
1031 audit_remove_watch_rule(&e->rule);
1032
1033 if (e->rule.tree)
1034 audit_remove_tree_rule(&e->rule);
1035
1036 if (e->rule.exe)
1037 audit_remove_mark_rule(&e->rule);
1038
1039 #ifdef CONFIG_AUDITSYSCALL
1040 if (!dont_count)
1041 audit_n_rules--;
1042
1043 if (!audit_match_signal(entry))
1044 audit_signals--;
1045 #endif
1046
1047 list_del_rcu(&e->list);
1048 list_del(&e->rule.list);
1049 call_rcu(&e->rcu, audit_free_rule_rcu);
1050
1051 out:
1052 mutex_unlock(&audit_filter_mutex);
1053
1054 if (tree)
1055 audit_put_tree(tree); /* that's the temporary one */
1056
1057 return ret;
1058 }
1059
1060 /* List rules using struct audit_rule_data. */
1061 static void audit_list_rules(int seq, struct sk_buff_head *q)
1062 {
1063 struct sk_buff *skb;
1064 struct audit_krule *r;
1065 int i;
1066
1067 /* This is a blocking read, so use audit_filter_mutex instead of rcu
1068 * iterator to sync with list writers. */
1069 for (i=0; i<AUDIT_NR_FILTERS; i++) {
1070 list_for_each_entry(r, &audit_rules_list[i], list) {
1071 struct audit_rule_data *data;
1072
1073 data = audit_krule_to_data(r);
1074 if (unlikely(!data))
1075 break;
1076 skb = audit_make_reply(seq, AUDIT_LIST_RULES, 0, 1,
1077 data,
1078 sizeof(*data) + data->buflen);
1079 if (skb)
1080 skb_queue_tail(q, skb);
1081 kfree(data);
1082 }
1083 }
1084 skb = audit_make_reply(seq, AUDIT_LIST_RULES, 1, 1, NULL, 0);
1085 if (skb)
1086 skb_queue_tail(q, skb);
1087 }
1088
1089 /* Log rule additions and removals */
1090 static void audit_log_rule_change(char *action, struct audit_krule *rule, int res)
1091 {
1092 struct audit_buffer *ab;
1093 uid_t loginuid = from_kuid(&init_user_ns, audit_get_loginuid(current));
1094 unsigned int sessionid = audit_get_sessionid(current);
1095
1096 if (!audit_enabled)
1097 return;
1098
1099 ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
1100 if (!ab)
1101 return;
1102 audit_log_format(ab, "auid=%u ses=%u" ,loginuid, sessionid);
1103 audit_log_task_context(ab);
1104 audit_log_format(ab, " op=%s", action);
1105 audit_log_key(ab, rule->filterkey);
1106 audit_log_format(ab, " list=%d res=%d", rule->listnr, res);
1107 audit_log_end(ab);
1108 }
1109
1110 /**
1111 * audit_rule_change - apply all rules to the specified message type
1112 * @type: audit message type
1113 * @seq: netlink audit message sequence (serial) number
1114 * @data: payload data
1115 * @datasz: size of payload data
1116 */
1117 int audit_rule_change(int type, int seq, void *data, size_t datasz)
1118 {
1119 int err = 0;
1120 struct audit_entry *entry;
1121
1122 switch (type) {
1123 case AUDIT_ADD_RULE:
1124 entry = audit_data_to_entry(data, datasz);
1125 if (IS_ERR(entry))
1126 return PTR_ERR(entry);
1127 err = audit_add_rule(entry);
1128 audit_log_rule_change("add_rule", &entry->rule, !err);
1129 break;
1130 case AUDIT_DEL_RULE:
1131 entry = audit_data_to_entry(data, datasz);
1132 if (IS_ERR(entry))
1133 return PTR_ERR(entry);
1134 err = audit_del_rule(entry);
1135 audit_log_rule_change("remove_rule", &entry->rule, !err);
1136 break;
1137 default:
1138 WARN_ON(1);
1139 return -EINVAL;
1140 }
1141
1142 if (err || type == AUDIT_DEL_RULE) {
1143 if (entry->rule.exe)
1144 audit_remove_mark(entry->rule.exe);
1145 audit_free_rule(entry);
1146 }
1147
1148 return err;
1149 }
1150
1151 /**
1152 * audit_list_rules_send - list the audit rules
1153 * @request_skb: skb of request we are replying to (used to target the reply)
1154 * @seq: netlink audit message sequence (serial) number
1155 */
1156 int audit_list_rules_send(struct sk_buff *request_skb, int seq)
1157 {
1158 u32 portid = NETLINK_CB(request_skb).portid;
1159 struct net *net = sock_net(NETLINK_CB(request_skb).sk);
1160 struct task_struct *tsk;
1161 struct audit_netlink_list *dest;
1162 int err = 0;
1163
1164 /* We can't just spew out the rules here because we might fill
1165 * the available socket buffer space and deadlock waiting for
1166 * auditctl to read from it... which isn't ever going to
1167 * happen if we're actually running in the context of auditctl
1168 * trying to _send_ the stuff */
1169
1170 dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL);
1171 if (!dest)
1172 return -ENOMEM;
1173 dest->net = get_net(net);
1174 dest->portid = portid;
1175 skb_queue_head_init(&dest->q);
1176
1177 mutex_lock(&audit_filter_mutex);
1178 audit_list_rules(seq, &dest->q);
1179 mutex_unlock(&audit_filter_mutex);
1180
1181 tsk = kthread_run(audit_send_list, dest, "audit_send_list");
1182 if (IS_ERR(tsk)) {
1183 skb_queue_purge(&dest->q);
1184 kfree(dest);
1185 err = PTR_ERR(tsk);
1186 }
1187
1188 return err;
1189 }
1190
1191 int audit_comparator(u32 left, u32 op, u32 right)
1192 {
1193 switch (op) {
1194 case Audit_equal:
1195 return (left == right);
1196 case Audit_not_equal:
1197 return (left != right);
1198 case Audit_lt:
1199 return (left < right);
1200 case Audit_le:
1201 return (left <= right);
1202 case Audit_gt:
1203 return (left > right);
1204 case Audit_ge:
1205 return (left >= right);
1206 case Audit_bitmask:
1207 return (left & right);
1208 case Audit_bittest:
1209 return ((left & right) == right);
1210 default:
1211 BUG();
1212 return 0;
1213 }
1214 }
1215
1216 int audit_uid_comparator(kuid_t left, u32 op, kuid_t right)
1217 {
1218 switch (op) {
1219 case Audit_equal:
1220 return uid_eq(left, right);
1221 case Audit_not_equal:
1222 return !uid_eq(left, right);
1223 case Audit_lt:
1224 return uid_lt(left, right);
1225 case Audit_le:
1226 return uid_lte(left, right);
1227 case Audit_gt:
1228 return uid_gt(left, right);
1229 case Audit_ge:
1230 return uid_gte(left, right);
1231 case Audit_bitmask:
1232 case Audit_bittest:
1233 default:
1234 BUG();
1235 return 0;
1236 }
1237 }
1238
1239 int audit_gid_comparator(kgid_t left, u32 op, kgid_t right)
1240 {
1241 switch (op) {
1242 case Audit_equal:
1243 return gid_eq(left, right);
1244 case Audit_not_equal:
1245 return !gid_eq(left, right);
1246 case Audit_lt:
1247 return gid_lt(left, right);
1248 case Audit_le:
1249 return gid_lte(left, right);
1250 case Audit_gt:
1251 return gid_gt(left, right);
1252 case Audit_ge:
1253 return gid_gte(left, right);
1254 case Audit_bitmask:
1255 case Audit_bittest:
1256 default:
1257 BUG();
1258 return 0;
1259 }
1260 }
1261
1262 /**
1263 * parent_len - find the length of the parent portion of a pathname
1264 * @path: pathname of which to determine length
1265 */
1266 int parent_len(const char *path)
1267 {
1268 int plen;
1269 const char *p;
1270
1271 plen = strlen(path);
1272
1273 if (plen == 0)
1274 return plen;
1275
1276 /* disregard trailing slashes */
1277 p = path + plen - 1;
1278 while ((*p == '/') && (p > path))
1279 p--;
1280
1281 /* walk backward until we find the next slash or hit beginning */
1282 while ((*p != '/') && (p > path))
1283 p--;
1284
1285 /* did we find a slash? Then increment to include it in path */
1286 if (*p == '/')
1287 p++;
1288
1289 return p - path;
1290 }
1291
1292 /**
1293 * audit_compare_dname_path - compare given dentry name with last component in
1294 * given path. Return of 0 indicates a match.
1295 * @dname: dentry name that we're comparing
1296 * @path: full pathname that we're comparing
1297 * @parentlen: length of the parent if known. Passing in AUDIT_NAME_FULL
1298 * here indicates that we must compute this value.
1299 */
1300 int audit_compare_dname_path(const char *dname, const char *path, int parentlen)
1301 {
1302 int dlen, pathlen;
1303 const char *p;
1304
1305 dlen = strlen(dname);
1306 pathlen = strlen(path);
1307 if (pathlen < dlen)
1308 return 1;
1309
1310 parentlen = parentlen == AUDIT_NAME_FULL ? parent_len(path) : parentlen;
1311 if (pathlen - parentlen != dlen)
1312 return 1;
1313
1314 p = path + parentlen;
1315
1316 return strncmp(p, dname, dlen);
1317 }
1318
1319 int audit_filter(int msgtype, unsigned int listtype)
1320 {
1321 struct audit_entry *e;
1322 int ret = 1; /* Audit by default */
1323
1324 rcu_read_lock();
1325 if (list_empty(&audit_filter_list[listtype]))
1326 goto unlock_and_return;
1327 list_for_each_entry_rcu(e, &audit_filter_list[listtype], list) {
1328 int i, result = 0;
1329
1330 for (i = 0; i < e->rule.field_count; i++) {
1331 struct audit_field *f = &e->rule.fields[i];
1332 pid_t pid;
1333 u32 sid;
1334
1335 switch (f->type) {
1336 case AUDIT_PID:
1337 pid = task_pid_nr(current);
1338 result = audit_comparator(pid, f->op, f->val);
1339 break;
1340 case AUDIT_UID:
1341 result = audit_uid_comparator(current_uid(), f->op, f->uid);
1342 break;
1343 case AUDIT_GID:
1344 result = audit_gid_comparator(current_gid(), f->op, f->gid);
1345 break;
1346 case AUDIT_LOGINUID:
1347 result = audit_uid_comparator(audit_get_loginuid(current),
1348 f->op, f->uid);
1349 break;
1350 case AUDIT_LOGINUID_SET:
1351 result = audit_comparator(audit_loginuid_set(current),
1352 f->op, f->val);
1353 break;
1354 case AUDIT_MSGTYPE:
1355 result = audit_comparator(msgtype, f->op, f->val);
1356 break;
1357 case AUDIT_SUBJ_USER:
1358 case AUDIT_SUBJ_ROLE:
1359 case AUDIT_SUBJ_TYPE:
1360 case AUDIT_SUBJ_SEN:
1361 case AUDIT_SUBJ_CLR:
1362 if (f->lsm_rule) {
1363 security_task_getsecid(current, &sid);
1364 result = security_audit_rule_match(sid,
1365 f->type, f->op, f->lsm_rule, NULL);
1366 }
1367 break;
1368 default:
1369 goto unlock_and_return;
1370 }
1371 if (result < 0) /* error */
1372 goto unlock_and_return;
1373 if (!result)
1374 break;
1375 }
1376 if (result > 0) {
1377 if (e->rule.action == AUDIT_NEVER || listtype == AUDIT_FILTER_TYPE)
1378 ret = 0;
1379 break;
1380 }
1381 }
1382 unlock_and_return:
1383 rcu_read_unlock();
1384 return ret;
1385 }
1386
1387 static int update_lsm_rule(struct audit_krule *r)
1388 {
1389 struct audit_entry *entry = container_of(r, struct audit_entry, rule);
1390 struct audit_entry *nentry;
1391 int err = 0;
1392
1393 if (!security_audit_rule_known(r))
1394 return 0;
1395
1396 nentry = audit_dupe_rule(r);
1397 if (entry->rule.exe)
1398 audit_remove_mark(entry->rule.exe);
1399 if (IS_ERR(nentry)) {
1400 /* save the first error encountered for the
1401 * return value */
1402 err = PTR_ERR(nentry);
1403 audit_panic("error updating LSM filters");
1404 if (r->watch)
1405 list_del(&r->rlist);
1406 list_del_rcu(&entry->list);
1407 list_del(&r->list);
1408 } else {
1409 if (r->watch || r->tree)
1410 list_replace_init(&r->rlist, &nentry->rule.rlist);
1411 list_replace_rcu(&entry->list, &nentry->list);
1412 list_replace(&r->list, &nentry->rule.list);
1413 }
1414 call_rcu(&entry->rcu, audit_free_rule_rcu);
1415
1416 return err;
1417 }
1418
1419 /* This function will re-initialize the lsm_rule field of all applicable rules.
1420 * It will traverse the filter lists serarching for rules that contain LSM
1421 * specific filter fields. When such a rule is found, it is copied, the
1422 * LSM field is re-initialized, and the old rule is replaced with the
1423 * updated rule. */
1424 int audit_update_lsm_rules(void)
1425 {
1426 struct audit_krule *r, *n;
1427 int i, err = 0;
1428
1429 /* audit_filter_mutex synchronizes the writers */
1430 mutex_lock(&audit_filter_mutex);
1431
1432 for (i = 0; i < AUDIT_NR_FILTERS; i++) {
1433 list_for_each_entry_safe(r, n, &audit_rules_list[i], list) {
1434 int res = update_lsm_rule(r);
1435 if (!err)
1436 err = res;
1437 }
1438 }
1439 mutex_unlock(&audit_filter_mutex);
1440
1441 return err;
1442 }
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