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Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
74c3cbe3 | 2 | #include "audit.h" |
28a3a7eb | 3 | #include <linux/fsnotify_backend.h> |
74c3cbe3 AV |
4 | #include <linux/namei.h> |
5 | #include <linux/mount.h> | |
916d7576 | 6 | #include <linux/kthread.h> |
9d2378f8 | 7 | #include <linux/refcount.h> |
5a0e3ad6 | 8 | #include <linux/slab.h> |
74c3cbe3 AV |
9 | |
10 | struct audit_tree; | |
11 | struct audit_chunk; | |
12 | ||
13 | struct audit_tree { | |
9d2378f8 | 14 | refcount_t count; |
74c3cbe3 AV |
15 | int goner; |
16 | struct audit_chunk *root; | |
17 | struct list_head chunks; | |
18 | struct list_head rules; | |
19 | struct list_head list; | |
20 | struct list_head same_root; | |
21 | struct rcu_head head; | |
22 | char pathname[]; | |
23 | }; | |
24 | ||
25 | struct audit_chunk { | |
26 | struct list_head hash; | |
8d20d6e9 | 27 | unsigned long key; |
5f516130 | 28 | struct fsnotify_mark *mark; |
74c3cbe3 | 29 | struct list_head trees; /* with root here */ |
74c3cbe3 | 30 | int count; |
8f7b0ba1 | 31 | atomic_long_t refs; |
74c3cbe3 AV |
32 | struct rcu_head head; |
33 | struct node { | |
34 | struct list_head list; | |
35 | struct audit_tree *owner; | |
36 | unsigned index; /* index; upper bit indicates 'will prune' */ | |
37 | } owners[]; | |
38 | }; | |
39 | ||
5f516130 JK |
40 | struct audit_tree_mark { |
41 | struct fsnotify_mark mark; | |
42 | struct audit_chunk *chunk; | |
43 | }; | |
44 | ||
74c3cbe3 AV |
45 | static LIST_HEAD(tree_list); |
46 | static LIST_HEAD(prune_list); | |
f1aaf262 | 47 | static struct task_struct *prune_thread; |
74c3cbe3 AV |
48 | |
49 | /* | |
83d23bc8 JK |
50 | * One struct chunk is attached to each inode of interest through |
51 | * audit_tree_mark (fsnotify mark). We replace struct chunk on tagging / | |
52 | * untagging, the mark is stable as long as there is chunk attached. The | |
53 | * association between mark and chunk is protected by hash_lock and | |
54 | * audit_tree_group->mark_mutex. Thus as long as we hold | |
55 | * audit_tree_group->mark_mutex and check that the mark is alive by | |
56 | * FSNOTIFY_MARK_FLAG_ATTACHED flag check, we are sure the mark points to | |
57 | * the current chunk. | |
58 | * | |
74c3cbe3 AV |
59 | * Rules have pointer to struct audit_tree. |
60 | * Rules have struct list_head rlist forming a list of rules over | |
61 | * the same tree. | |
62 | * References to struct chunk are collected at audit_inode{,_child}() | |
63 | * time and used in AUDIT_TREE rule matching. | |
64 | * These references are dropped at the same time we are calling | |
65 | * audit_free_names(), etc. | |
66 | * | |
67 | * Cyclic lists galore: | |
68 | * tree.chunks anchors chunk.owners[].list hash_lock | |
69 | * tree.rules anchors rule.rlist audit_filter_mutex | |
70 | * chunk.trees anchors tree.same_root hash_lock | |
71 | * chunk.hash is a hash with middle bits of watch.inode as | |
72 | * a hash function. RCU, hash_lock | |
73 | * | |
74 | * tree is refcounted; one reference for "some rules on rules_list refer to | |
75 | * it", one for each chunk with pointer to it. | |
76 | * | |
83d23bc8 JK |
77 | * chunk is refcounted by embedded .refs. Mark associated with the chunk holds |
78 | * one chunk reference. This reference is dropped either when a mark is going | |
79 | * to be freed (corresponding inode goes away) or when chunk attached to the | |
80 | * mark gets replaced. This reference must be dropped using | |
81 | * audit_mark_put_chunk() to make sure the reference is dropped only after RCU | |
82 | * grace period as it protects RCU readers of the hash table. | |
74c3cbe3 AV |
83 | * |
84 | * node.index allows to get from node.list to containing chunk. | |
85 | * MSB of that sucker is stolen to mark taggings that we might have to | |
86 | * revert - several operations have very unpleasant cleanup logics and | |
87 | * that makes a difference. Some. | |
88 | */ | |
89 | ||
28a3a7eb | 90 | static struct fsnotify_group *audit_tree_group; |
5f516130 | 91 | static struct kmem_cache *audit_tree_mark_cachep __read_mostly; |
74c3cbe3 AV |
92 | |
93 | static struct audit_tree *alloc_tree(const char *s) | |
94 | { | |
95 | struct audit_tree *tree; | |
96 | ||
97 | tree = kmalloc(sizeof(struct audit_tree) + strlen(s) + 1, GFP_KERNEL); | |
98 | if (tree) { | |
9d2378f8 | 99 | refcount_set(&tree->count, 1); |
74c3cbe3 AV |
100 | tree->goner = 0; |
101 | INIT_LIST_HEAD(&tree->chunks); | |
102 | INIT_LIST_HEAD(&tree->rules); | |
103 | INIT_LIST_HEAD(&tree->list); | |
104 | INIT_LIST_HEAD(&tree->same_root); | |
105 | tree->root = NULL; | |
106 | strcpy(tree->pathname, s); | |
107 | } | |
108 | return tree; | |
109 | } | |
110 | ||
111 | static inline void get_tree(struct audit_tree *tree) | |
112 | { | |
9d2378f8 | 113 | refcount_inc(&tree->count); |
74c3cbe3 AV |
114 | } |
115 | ||
74c3cbe3 AV |
116 | static inline void put_tree(struct audit_tree *tree) |
117 | { | |
9d2378f8 | 118 | if (refcount_dec_and_test(&tree->count)) |
3b097c46 | 119 | kfree_rcu(tree, head); |
74c3cbe3 AV |
120 | } |
121 | ||
122 | /* to avoid bringing the entire thing in audit.h */ | |
123 | const char *audit_tree_path(struct audit_tree *tree) | |
124 | { | |
125 | return tree->pathname; | |
126 | } | |
127 | ||
8f7b0ba1 | 128 | static void free_chunk(struct audit_chunk *chunk) |
74c3cbe3 | 129 | { |
74c3cbe3 AV |
130 | int i; |
131 | ||
132 | for (i = 0; i < chunk->count; i++) { | |
133 | if (chunk->owners[i].owner) | |
134 | put_tree(chunk->owners[i].owner); | |
135 | } | |
136 | kfree(chunk); | |
137 | } | |
138 | ||
8f7b0ba1 | 139 | void audit_put_chunk(struct audit_chunk *chunk) |
74c3cbe3 | 140 | { |
8f7b0ba1 AV |
141 | if (atomic_long_dec_and_test(&chunk->refs)) |
142 | free_chunk(chunk); | |
74c3cbe3 AV |
143 | } |
144 | ||
8f7b0ba1 | 145 | static void __put_chunk(struct rcu_head *rcu) |
74c3cbe3 | 146 | { |
8f7b0ba1 AV |
147 | struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head); |
148 | audit_put_chunk(chunk); | |
74c3cbe3 AV |
149 | } |
150 | ||
a8375713 JK |
151 | /* |
152 | * Drop reference to the chunk that was held by the mark. This is the reference | |
153 | * that gets dropped after we've removed the chunk from the hash table and we | |
154 | * use it to make sure chunk cannot be freed before RCU grace period expires. | |
155 | */ | |
156 | static void audit_mark_put_chunk(struct audit_chunk *chunk) | |
157 | { | |
158 | call_rcu(&chunk->head, __put_chunk); | |
159 | } | |
160 | ||
f905c2fc | 161 | static inline struct audit_tree_mark *audit_mark(struct fsnotify_mark *mark) |
5f516130 | 162 | { |
f905c2fc | 163 | return container_of(mark, struct audit_tree_mark, mark); |
5f516130 JK |
164 | } |
165 | ||
166 | static struct audit_chunk *mark_chunk(struct fsnotify_mark *mark) | |
167 | { | |
168 | return audit_mark(mark)->chunk; | |
169 | } | |
170 | ||
f905c2fc | 171 | static void audit_tree_destroy_watch(struct fsnotify_mark *mark) |
28a3a7eb | 172 | { |
f905c2fc | 173 | kmem_cache_free(audit_tree_mark_cachep, audit_mark(mark)); |
5f516130 JK |
174 | } |
175 | ||
176 | static struct fsnotify_mark *alloc_mark(void) | |
177 | { | |
178 | struct audit_tree_mark *amark; | |
179 | ||
180 | amark = kmem_cache_zalloc(audit_tree_mark_cachep, GFP_KERNEL); | |
181 | if (!amark) | |
182 | return NULL; | |
183 | fsnotify_init_mark(&amark->mark, audit_tree_group); | |
184 | amark->mark.mask = FS_IN_IGNORED; | |
185 | return &amark->mark; | |
28a3a7eb EP |
186 | } |
187 | ||
188 | static struct audit_chunk *alloc_chunk(int count) | |
189 | { | |
190 | struct audit_chunk *chunk; | |
28a3a7eb EP |
191 | int i; |
192 | ||
bbccc11b | 193 | chunk = kzalloc(struct_size(chunk, owners, count), GFP_KERNEL); |
28a3a7eb EP |
194 | if (!chunk) |
195 | return NULL; | |
196 | ||
197 | INIT_LIST_HEAD(&chunk->hash); | |
198 | INIT_LIST_HEAD(&chunk->trees); | |
199 | chunk->count = count; | |
200 | atomic_long_set(&chunk->refs, 1); | |
201 | for (i = 0; i < count; i++) { | |
202 | INIT_LIST_HEAD(&chunk->owners[i].list); | |
203 | chunk->owners[i].index = i; | |
204 | } | |
28a3a7eb EP |
205 | return chunk; |
206 | } | |
207 | ||
74c3cbe3 AV |
208 | enum {HASH_SIZE = 128}; |
209 | static struct list_head chunk_hash_heads[HASH_SIZE]; | |
210 | static __cacheline_aligned_in_smp DEFINE_SPINLOCK(hash_lock); | |
211 | ||
f410ff65 JK |
212 | /* Function to return search key in our hash from inode. */ |
213 | static unsigned long inode_to_key(const struct inode *inode) | |
74c3cbe3 | 214 | { |
36f10f55 AG |
215 | /* Use address pointed to by connector->obj as the key */ |
216 | return (unsigned long)&inode->i_fsnotify_marks; | |
f410ff65 JK |
217 | } |
218 | ||
f410ff65 JK |
219 | static inline struct list_head *chunk_hash(unsigned long key) |
220 | { | |
221 | unsigned long n = key / L1_CACHE_BYTES; | |
74c3cbe3 AV |
222 | return chunk_hash_heads + n % HASH_SIZE; |
223 | } | |
224 | ||
f905c2fc | 225 | /* hash_lock & mark->group->mark_mutex is held by caller */ |
74c3cbe3 AV |
226 | static void insert_hash(struct audit_chunk *chunk) |
227 | { | |
28a3a7eb EP |
228 | struct list_head *list; |
229 | ||
1635e572 JK |
230 | /* |
231 | * Make sure chunk is fully initialized before making it visible in the | |
232 | * hash. Pairs with a data dependency barrier in READ_ONCE() in | |
233 | * audit_tree_lookup(). | |
234 | */ | |
235 | smp_wmb(); | |
8d20d6e9 JK |
236 | WARN_ON_ONCE(!chunk->key); |
237 | list = chunk_hash(chunk->key); | |
74c3cbe3 AV |
238 | list_add_rcu(&chunk->hash, list); |
239 | } | |
240 | ||
241 | /* called under rcu_read_lock */ | |
242 | struct audit_chunk *audit_tree_lookup(const struct inode *inode) | |
243 | { | |
f410ff65 JK |
244 | unsigned long key = inode_to_key(inode); |
245 | struct list_head *list = chunk_hash(key); | |
6793a051 | 246 | struct audit_chunk *p; |
74c3cbe3 | 247 | |
6793a051 | 248 | list_for_each_entry_rcu(p, list, hash) { |
1635e572 JK |
249 | /* |
250 | * We use a data dependency barrier in READ_ONCE() to make sure | |
251 | * the chunk we see is fully initialized. | |
252 | */ | |
253 | if (READ_ONCE(p->key) == key) { | |
8f7b0ba1 | 254 | atomic_long_inc(&p->refs); |
74c3cbe3 AV |
255 | return p; |
256 | } | |
257 | } | |
258 | return NULL; | |
259 | } | |
260 | ||
6f1b5d7a | 261 | bool audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree) |
74c3cbe3 AV |
262 | { |
263 | int n; | |
264 | for (n = 0; n < chunk->count; n++) | |
265 | if (chunk->owners[n].owner == tree) | |
6f1b5d7a YB |
266 | return true; |
267 | return false; | |
74c3cbe3 AV |
268 | } |
269 | ||
270 | /* tagging and untagging inodes with trees */ | |
271 | ||
8f7b0ba1 AV |
272 | static struct audit_chunk *find_chunk(struct node *p) |
273 | { | |
274 | int index = p->index & ~(1U<<31); | |
275 | p -= index; | |
276 | return container_of(p, struct audit_chunk, owners[0]); | |
277 | } | |
278 | ||
f905c2fc | 279 | static void replace_mark_chunk(struct fsnotify_mark *mark, |
83d23bc8 JK |
280 | struct audit_chunk *chunk) |
281 | { | |
282 | struct audit_chunk *old; | |
283 | ||
284 | assert_spin_locked(&hash_lock); | |
f905c2fc JK |
285 | old = mark_chunk(mark); |
286 | audit_mark(mark)->chunk = chunk; | |
83d23bc8 | 287 | if (chunk) |
f905c2fc | 288 | chunk->mark = mark; |
83d23bc8 JK |
289 | if (old) |
290 | old->mark = NULL; | |
291 | } | |
292 | ||
c22fcde7 | 293 | static void replace_chunk(struct audit_chunk *new, struct audit_chunk *old) |
d31b326d JK |
294 | { |
295 | struct audit_tree *owner; | |
296 | int i, j; | |
297 | ||
298 | new->key = old->key; | |
299 | list_splice_init(&old->trees, &new->trees); | |
300 | list_for_each_entry(owner, &new->trees, same_root) | |
301 | owner->root = new; | |
302 | for (i = j = 0; j < old->count; i++, j++) { | |
c22fcde7 | 303 | if (!old->owners[j].owner) { |
d31b326d JK |
304 | i--; |
305 | continue; | |
306 | } | |
307 | owner = old->owners[j].owner; | |
308 | new->owners[i].owner = owner; | |
309 | new->owners[i].index = old->owners[j].index - j + i; | |
310 | if (!owner) /* result of earlier fallback */ | |
311 | continue; | |
312 | get_tree(owner); | |
313 | list_replace_init(&old->owners[j].list, &new->owners[i].list); | |
314 | } | |
83d23bc8 | 315 | replace_mark_chunk(old->mark, new); |
d31b326d JK |
316 | /* |
317 | * Make sure chunk is fully initialized before making it visible in the | |
318 | * hash. Pairs with a data dependency barrier in READ_ONCE() in | |
319 | * audit_tree_lookup(). | |
320 | */ | |
321 | smp_wmb(); | |
322 | list_replace_rcu(&old->hash, &new->hash); | |
323 | } | |
324 | ||
49a4ee7d JK |
325 | static void remove_chunk_node(struct audit_chunk *chunk, struct node *p) |
326 | { | |
327 | struct audit_tree *owner = p->owner; | |
328 | ||
329 | if (owner->root == chunk) { | |
330 | list_del_init(&owner->same_root); | |
331 | owner->root = NULL; | |
332 | } | |
333 | list_del_init(&p->list); | |
334 | p->owner = NULL; | |
335 | put_tree(owner); | |
336 | } | |
337 | ||
c22fcde7 JK |
338 | static int chunk_count_trees(struct audit_chunk *chunk) |
339 | { | |
340 | int i; | |
341 | int ret = 0; | |
342 | ||
343 | for (i = 0; i < chunk->count; i++) | |
344 | if (chunk->owners[i].owner) | |
345 | ret++; | |
346 | return ret; | |
347 | } | |
348 | ||
f905c2fc | 349 | static void untag_chunk(struct audit_chunk *chunk, struct fsnotify_mark *mark) |
74c3cbe3 | 350 | { |
8432c700 | 351 | struct audit_chunk *new; |
c22fcde7 | 352 | int size; |
74c3cbe3 | 353 | |
8432c700 | 354 | mutex_lock(&audit_tree_group->mark_mutex); |
6b3f05d2 | 355 | /* |
83d23bc8 JK |
356 | * mark_mutex stabilizes chunk attached to the mark so we can check |
357 | * whether it didn't change while we've dropped hash_lock. | |
6b3f05d2 | 358 | */ |
f905c2fc JK |
359 | if (!(mark->flags & FSNOTIFY_MARK_FLAG_ATTACHED) || |
360 | mark_chunk(mark) != chunk) | |
8432c700 | 361 | goto out_mutex; |
74c3cbe3 | 362 | |
c22fcde7 | 363 | size = chunk_count_trees(chunk); |
74c3cbe3 | 364 | if (!size) { |
74c3cbe3 AV |
365 | spin_lock(&hash_lock); |
366 | list_del_init(&chunk->trees); | |
74c3cbe3 | 367 | list_del_rcu(&chunk->hash); |
f905c2fc | 368 | replace_mark_chunk(mark, NULL); |
74c3cbe3 | 369 | spin_unlock(&hash_lock); |
f905c2fc | 370 | fsnotify_detach_mark(mark); |
8432c700 | 371 | mutex_unlock(&audit_tree_group->mark_mutex); |
83d23bc8 | 372 | audit_mark_put_chunk(chunk); |
f905c2fc | 373 | fsnotify_free_mark(mark); |
8432c700 | 374 | return; |
74c3cbe3 AV |
375 | } |
376 | ||
c22fcde7 | 377 | new = alloc_chunk(size); |
74c3cbe3 | 378 | if (!new) |
49a4ee7d | 379 | goto out_mutex; |
f7a998a9 | 380 | |
74c3cbe3 | 381 | spin_lock(&hash_lock); |
1635e572 | 382 | /* |
d31b326d JK |
383 | * This has to go last when updating chunk as once replace_chunk() is |
384 | * called, new RCU readers can see the new chunk. | |
1635e572 | 385 | */ |
c22fcde7 | 386 | replace_chunk(new, chunk); |
74c3cbe3 | 387 | spin_unlock(&hash_lock); |
8432c700 | 388 | mutex_unlock(&audit_tree_group->mark_mutex); |
83d23bc8 | 389 | audit_mark_put_chunk(chunk); |
8432c700 | 390 | return; |
74c3cbe3 | 391 | |
49a4ee7d | 392 | out_mutex: |
8432c700 | 393 | mutex_unlock(&audit_tree_group->mark_mutex); |
74c3cbe3 AV |
394 | } |
395 | ||
a5789b07 | 396 | /* Call with group->mark_mutex held, releases it */ |
74c3cbe3 AV |
397 | static int create_chunk(struct inode *inode, struct audit_tree *tree) |
398 | { | |
f905c2fc | 399 | struct fsnotify_mark *mark; |
74c3cbe3 | 400 | struct audit_chunk *chunk = alloc_chunk(1); |
a5789b07 JK |
401 | |
402 | if (!chunk) { | |
403 | mutex_unlock(&audit_tree_group->mark_mutex); | |
74c3cbe3 | 404 | return -ENOMEM; |
a5789b07 | 405 | } |
74c3cbe3 | 406 | |
f905c2fc JK |
407 | mark = alloc_mark(); |
408 | if (!mark) { | |
83d23bc8 JK |
409 | mutex_unlock(&audit_tree_group->mark_mutex); |
410 | kfree(chunk); | |
411 | return -ENOMEM; | |
412 | } | |
413 | ||
f905c2fc | 414 | if (fsnotify_add_inode_mark_locked(mark, inode, 0)) { |
a5789b07 | 415 | mutex_unlock(&audit_tree_group->mark_mutex); |
f905c2fc | 416 | fsnotify_put_mark(mark); |
83d23bc8 | 417 | kfree(chunk); |
74c3cbe3 AV |
418 | return -ENOSPC; |
419 | } | |
420 | ||
74c3cbe3 AV |
421 | spin_lock(&hash_lock); |
422 | if (tree->goner) { | |
423 | spin_unlock(&hash_lock); | |
f905c2fc | 424 | fsnotify_detach_mark(mark); |
a5789b07 | 425 | mutex_unlock(&audit_tree_group->mark_mutex); |
f905c2fc JK |
426 | fsnotify_free_mark(mark); |
427 | fsnotify_put_mark(mark); | |
83d23bc8 | 428 | kfree(chunk); |
74c3cbe3 AV |
429 | return 0; |
430 | } | |
f905c2fc | 431 | replace_mark_chunk(mark, chunk); |
74c3cbe3 AV |
432 | chunk->owners[0].index = (1U << 31); |
433 | chunk->owners[0].owner = tree; | |
434 | get_tree(tree); | |
435 | list_add(&chunk->owners[0].list, &tree->chunks); | |
436 | if (!tree->root) { | |
437 | tree->root = chunk; | |
438 | list_add(&tree->same_root, &chunk->trees); | |
439 | } | |
8d20d6e9 | 440 | chunk->key = inode_to_key(inode); |
1635e572 JK |
441 | /* |
442 | * Inserting into the hash table has to go last as once we do that RCU | |
443 | * readers can see the chunk. | |
444 | */ | |
74c3cbe3 AV |
445 | insert_hash(chunk); |
446 | spin_unlock(&hash_lock); | |
a5789b07 | 447 | mutex_unlock(&audit_tree_group->mark_mutex); |
83d23bc8 JK |
448 | /* |
449 | * Drop our initial reference. When mark we point to is getting freed, | |
450 | * we get notification through ->freeing_mark callback and cleanup | |
451 | * chunk pointing to this mark. | |
452 | */ | |
f905c2fc | 453 | fsnotify_put_mark(mark); |
74c3cbe3 AV |
454 | return 0; |
455 | } | |
456 | ||
457 | /* the first tagged inode becomes root of tree */ | |
458 | static int tag_chunk(struct inode *inode, struct audit_tree *tree) | |
459 | { | |
f905c2fc | 460 | struct fsnotify_mark *mark; |
74c3cbe3 AV |
461 | struct audit_chunk *chunk, *old; |
462 | struct node *p; | |
463 | int n; | |
464 | ||
a5789b07 | 465 | mutex_lock(&audit_tree_group->mark_mutex); |
f905c2fc JK |
466 | mark = fsnotify_find_mark(&inode->i_fsnotify_marks, audit_tree_group); |
467 | if (!mark) | |
74c3cbe3 AV |
468 | return create_chunk(inode, tree); |
469 | ||
83d23bc8 JK |
470 | /* |
471 | * Found mark is guaranteed to be attached and mark_mutex protects mark | |
472 | * from getting detached and thus it makes sure there is chunk attached | |
473 | * to the mark. | |
474 | */ | |
74c3cbe3 AV |
475 | /* are we already there? */ |
476 | spin_lock(&hash_lock); | |
f905c2fc | 477 | old = mark_chunk(mark); |
74c3cbe3 AV |
478 | for (n = 0; n < old->count; n++) { |
479 | if (old->owners[n].owner == tree) { | |
480 | spin_unlock(&hash_lock); | |
a5789b07 | 481 | mutex_unlock(&audit_tree_group->mark_mutex); |
f905c2fc | 482 | fsnotify_put_mark(mark); |
74c3cbe3 AV |
483 | return 0; |
484 | } | |
485 | } | |
486 | spin_unlock(&hash_lock); | |
487 | ||
488 | chunk = alloc_chunk(old->count + 1); | |
b4c30aad | 489 | if (!chunk) { |
a5789b07 | 490 | mutex_unlock(&audit_tree_group->mark_mutex); |
f905c2fc | 491 | fsnotify_put_mark(mark); |
74c3cbe3 | 492 | return -ENOMEM; |
b4c30aad | 493 | } |
74c3cbe3 | 494 | |
74c3cbe3 AV |
495 | spin_lock(&hash_lock); |
496 | if (tree->goner) { | |
497 | spin_unlock(&hash_lock); | |
a5789b07 | 498 | mutex_unlock(&audit_tree_group->mark_mutex); |
f905c2fc | 499 | fsnotify_put_mark(mark); |
83d23bc8 | 500 | kfree(chunk); |
74c3cbe3 AV |
501 | return 0; |
502 | } | |
d31b326d | 503 | p = &chunk->owners[chunk->count - 1]; |
74c3cbe3 AV |
504 | p->index = (chunk->count - 1) | (1U<<31); |
505 | p->owner = tree; | |
506 | get_tree(tree); | |
507 | list_add(&p->list, &tree->chunks); | |
74c3cbe3 AV |
508 | if (!tree->root) { |
509 | tree->root = chunk; | |
510 | list_add(&tree->same_root, &chunk->trees); | |
511 | } | |
1635e572 | 512 | /* |
d31b326d JK |
513 | * This has to go last when updating chunk as once replace_chunk() is |
514 | * called, new RCU readers can see the new chunk. | |
1635e572 | 515 | */ |
c22fcde7 | 516 | replace_chunk(chunk, old); |
74c3cbe3 | 517 | spin_unlock(&hash_lock); |
a5789b07 | 518 | mutex_unlock(&audit_tree_group->mark_mutex); |
f905c2fc | 519 | fsnotify_put_mark(mark); /* pair to fsnotify_find_mark */ |
83d23bc8 JK |
520 | audit_mark_put_chunk(old); |
521 | ||
74c3cbe3 AV |
522 | return 0; |
523 | } | |
524 | ||
9e36a5d4 RGB |
525 | static void audit_tree_log_remove_rule(struct audit_context *context, |
526 | struct audit_krule *rule) | |
0644ec0c KC |
527 | { |
528 | struct audit_buffer *ab; | |
529 | ||
65a8766f RGB |
530 | if (!audit_enabled) |
531 | return; | |
9e36a5d4 | 532 | ab = audit_log_start(context, GFP_KERNEL, AUDIT_CONFIG_CHANGE); |
0644ec0c KC |
533 | if (unlikely(!ab)) |
534 | return; | |
d0a3f18a | 535 | audit_log_format(ab, "op=remove_rule dir="); |
0644ec0c KC |
536 | audit_log_untrustedstring(ab, rule->tree->pathname); |
537 | audit_log_key(ab, rule->filterkey); | |
538 | audit_log_format(ab, " list=%d res=1", rule->listnr); | |
539 | audit_log_end(ab); | |
540 | } | |
541 | ||
9e36a5d4 | 542 | static void kill_rules(struct audit_context *context, struct audit_tree *tree) |
74c3cbe3 AV |
543 | { |
544 | struct audit_krule *rule, *next; | |
545 | struct audit_entry *entry; | |
74c3cbe3 AV |
546 | |
547 | list_for_each_entry_safe(rule, next, &tree->rules, rlist) { | |
548 | entry = container_of(rule, struct audit_entry, rule); | |
549 | ||
550 | list_del_init(&rule->rlist); | |
551 | if (rule->tree) { | |
552 | /* not a half-baked one */ | |
9e36a5d4 | 553 | audit_tree_log_remove_rule(context, rule); |
34d99af5 RGB |
554 | if (entry->rule.exe) |
555 | audit_remove_mark(entry->rule.exe); | |
74c3cbe3 AV |
556 | rule->tree = NULL; |
557 | list_del_rcu(&entry->list); | |
e45aa212 | 558 | list_del(&entry->rule.list); |
74c3cbe3 AV |
559 | call_rcu(&entry->rcu, audit_free_rule_rcu); |
560 | } | |
561 | } | |
562 | } | |
563 | ||
564 | /* | |
8432c700 JK |
565 | * Remove tree from chunks. If 'tagged' is set, remove tree only from tagged |
566 | * chunks. The function expects tagged chunks are all at the beginning of the | |
567 | * chunks list. | |
74c3cbe3 | 568 | */ |
8432c700 | 569 | static void prune_tree_chunks(struct audit_tree *victim, bool tagged) |
74c3cbe3 AV |
570 | { |
571 | spin_lock(&hash_lock); | |
572 | while (!list_empty(&victim->chunks)) { | |
573 | struct node *p; | |
8432c700 JK |
574 | struct audit_chunk *chunk; |
575 | struct fsnotify_mark *mark; | |
576 | ||
577 | p = list_first_entry(&victim->chunks, struct node, list); | |
578 | /* have we run out of marked? */ | |
579 | if (tagged && !(p->index & (1U<<31))) | |
580 | break; | |
581 | chunk = find_chunk(p); | |
582 | mark = chunk->mark; | |
583 | remove_chunk_node(chunk, p); | |
83d23bc8 JK |
584 | /* Racing with audit_tree_freeing_mark()? */ |
585 | if (!mark) | |
586 | continue; | |
8432c700 JK |
587 | fsnotify_get_mark(mark); |
588 | spin_unlock(&hash_lock); | |
74c3cbe3 | 589 | |
8432c700 JK |
590 | untag_chunk(chunk, mark); |
591 | fsnotify_put_mark(mark); | |
74c3cbe3 | 592 | |
8432c700 | 593 | spin_lock(&hash_lock); |
74c3cbe3 AV |
594 | } |
595 | spin_unlock(&hash_lock); | |
596 | put_tree(victim); | |
597 | } | |
598 | ||
8432c700 JK |
599 | /* |
600 | * finish killing struct audit_tree | |
601 | */ | |
602 | static void prune_one(struct audit_tree *victim) | |
603 | { | |
604 | prune_tree_chunks(victim, false); | |
605 | } | |
606 | ||
74c3cbe3 AV |
607 | /* trim the uncommitted chunks from tree */ |
608 | ||
609 | static void trim_marked(struct audit_tree *tree) | |
610 | { | |
611 | struct list_head *p, *q; | |
612 | spin_lock(&hash_lock); | |
613 | if (tree->goner) { | |
614 | spin_unlock(&hash_lock); | |
615 | return; | |
616 | } | |
617 | /* reorder */ | |
618 | for (p = tree->chunks.next; p != &tree->chunks; p = q) { | |
619 | struct node *node = list_entry(p, struct node, list); | |
620 | q = p->next; | |
621 | if (node->index & (1U<<31)) { | |
622 | list_del_init(p); | |
623 | list_add(p, &tree->chunks); | |
624 | } | |
625 | } | |
8432c700 | 626 | spin_unlock(&hash_lock); |
74c3cbe3 | 627 | |
8432c700 | 628 | prune_tree_chunks(tree, true); |
74c3cbe3 | 629 | |
8432c700 | 630 | spin_lock(&hash_lock); |
74c3cbe3 AV |
631 | if (!tree->root && !tree->goner) { |
632 | tree->goner = 1; | |
633 | spin_unlock(&hash_lock); | |
634 | mutex_lock(&audit_filter_mutex); | |
9e36a5d4 | 635 | kill_rules(audit_context(), tree); |
74c3cbe3 AV |
636 | list_del_init(&tree->list); |
637 | mutex_unlock(&audit_filter_mutex); | |
638 | prune_one(tree); | |
639 | } else { | |
640 | spin_unlock(&hash_lock); | |
641 | } | |
642 | } | |
643 | ||
916d7576 AV |
644 | static void audit_schedule_prune(void); |
645 | ||
74c3cbe3 AV |
646 | /* called with audit_filter_mutex */ |
647 | int audit_remove_tree_rule(struct audit_krule *rule) | |
648 | { | |
649 | struct audit_tree *tree; | |
650 | tree = rule->tree; | |
651 | if (tree) { | |
652 | spin_lock(&hash_lock); | |
653 | list_del_init(&rule->rlist); | |
654 | if (list_empty(&tree->rules) && !tree->goner) { | |
655 | tree->root = NULL; | |
656 | list_del_init(&tree->same_root); | |
657 | tree->goner = 1; | |
658 | list_move(&tree->list, &prune_list); | |
659 | rule->tree = NULL; | |
660 | spin_unlock(&hash_lock); | |
661 | audit_schedule_prune(); | |
662 | return 1; | |
663 | } | |
664 | rule->tree = NULL; | |
665 | spin_unlock(&hash_lock); | |
666 | return 1; | |
667 | } | |
668 | return 0; | |
669 | } | |
670 | ||
1f707137 AV |
671 | static int compare_root(struct vfsmount *mnt, void *arg) |
672 | { | |
f410ff65 JK |
673 | return inode_to_key(d_backing_inode(mnt->mnt_root)) == |
674 | (unsigned long)arg; | |
1f707137 AV |
675 | } |
676 | ||
74c3cbe3 AV |
677 | void audit_trim_trees(void) |
678 | { | |
679 | struct list_head cursor; | |
680 | ||
681 | mutex_lock(&audit_filter_mutex); | |
682 | list_add(&cursor, &tree_list); | |
683 | while (cursor.next != &tree_list) { | |
684 | struct audit_tree *tree; | |
98bc993f | 685 | struct path path; |
74c3cbe3 AV |
686 | struct vfsmount *root_mnt; |
687 | struct node *node; | |
74c3cbe3 AV |
688 | int err; |
689 | ||
690 | tree = container_of(cursor.next, struct audit_tree, list); | |
691 | get_tree(tree); | |
692 | list_del(&cursor); | |
693 | list_add(&cursor, &tree->list); | |
694 | mutex_unlock(&audit_filter_mutex); | |
695 | ||
98bc993f | 696 | err = kern_path(tree->pathname, 0, &path); |
74c3cbe3 AV |
697 | if (err) |
698 | goto skip_it; | |
699 | ||
589ff870 | 700 | root_mnt = collect_mounts(&path); |
98bc993f | 701 | path_put(&path); |
be34d1a3 | 702 | if (IS_ERR(root_mnt)) |
74c3cbe3 AV |
703 | goto skip_it; |
704 | ||
74c3cbe3 AV |
705 | spin_lock(&hash_lock); |
706 | list_for_each_entry(node, &tree->chunks, list) { | |
28a3a7eb | 707 | struct audit_chunk *chunk = find_chunk(node); |
25985edc | 708 | /* this could be NULL if the watch is dying else where... */ |
74c3cbe3 | 709 | node->index |= 1U<<31; |
f410ff65 | 710 | if (iterate_mounts(compare_root, |
8d20d6e9 | 711 | (void *)(chunk->key), |
f410ff65 | 712 | root_mnt)) |
1f707137 | 713 | node->index &= ~(1U<<31); |
74c3cbe3 AV |
714 | } |
715 | spin_unlock(&hash_lock); | |
716 | trim_marked(tree); | |
74c3cbe3 AV |
717 | drop_collected_mounts(root_mnt); |
718 | skip_it: | |
12b2f117 | 719 | put_tree(tree); |
74c3cbe3 AV |
720 | mutex_lock(&audit_filter_mutex); |
721 | } | |
722 | list_del(&cursor); | |
723 | mutex_unlock(&audit_filter_mutex); | |
724 | } | |
725 | ||
74c3cbe3 AV |
726 | int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op) |
727 | { | |
728 | ||
729 | if (pathname[0] != '/' || | |
730 | rule->listnr != AUDIT_FILTER_EXIT || | |
5af75d8d | 731 | op != Audit_equal || |
74c3cbe3 AV |
732 | rule->inode_f || rule->watch || rule->tree) |
733 | return -EINVAL; | |
734 | rule->tree = alloc_tree(pathname); | |
735 | if (!rule->tree) | |
736 | return -ENOMEM; | |
737 | return 0; | |
738 | } | |
739 | ||
740 | void audit_put_tree(struct audit_tree *tree) | |
741 | { | |
742 | put_tree(tree); | |
743 | } | |
744 | ||
1f707137 AV |
745 | static int tag_mount(struct vfsmount *mnt, void *arg) |
746 | { | |
3b362157 | 747 | return tag_chunk(d_backing_inode(mnt->mnt_root), arg); |
1f707137 AV |
748 | } |
749 | ||
f1aaf262 IP |
750 | /* |
751 | * That gets run when evict_chunk() ends up needing to kill audit_tree. | |
752 | * Runs from a separate thread. | |
753 | */ | |
754 | static int prune_tree_thread(void *unused) | |
755 | { | |
756 | for (;;) { | |
0bf676d1 JS |
757 | if (list_empty(&prune_list)) { |
758 | set_current_state(TASK_INTERRUPTIBLE); | |
f1aaf262 | 759 | schedule(); |
0bf676d1 | 760 | } |
f1aaf262 | 761 | |
ce423631 | 762 | audit_ctl_lock(); |
f1aaf262 IP |
763 | mutex_lock(&audit_filter_mutex); |
764 | ||
765 | while (!list_empty(&prune_list)) { | |
766 | struct audit_tree *victim; | |
767 | ||
768 | victim = list_entry(prune_list.next, | |
769 | struct audit_tree, list); | |
770 | list_del_init(&victim->list); | |
771 | ||
772 | mutex_unlock(&audit_filter_mutex); | |
773 | ||
774 | prune_one(victim); | |
775 | ||
776 | mutex_lock(&audit_filter_mutex); | |
777 | } | |
778 | ||
779 | mutex_unlock(&audit_filter_mutex); | |
ce423631 | 780 | audit_ctl_unlock(); |
f1aaf262 IP |
781 | } |
782 | return 0; | |
783 | } | |
784 | ||
785 | static int audit_launch_prune(void) | |
786 | { | |
787 | if (prune_thread) | |
788 | return 0; | |
0bf676d1 | 789 | prune_thread = kthread_run(prune_tree_thread, NULL, |
f1aaf262 IP |
790 | "audit_prune_tree"); |
791 | if (IS_ERR(prune_thread)) { | |
792 | pr_err("cannot start thread audit_prune_tree"); | |
793 | prune_thread = NULL; | |
794 | return -ENOMEM; | |
f1aaf262 | 795 | } |
0bf676d1 | 796 | return 0; |
f1aaf262 IP |
797 | } |
798 | ||
74c3cbe3 AV |
799 | /* called with audit_filter_mutex */ |
800 | int audit_add_tree_rule(struct audit_krule *rule) | |
801 | { | |
802 | struct audit_tree *seed = rule->tree, *tree; | |
98bc993f | 803 | struct path path; |
1f707137 | 804 | struct vfsmount *mnt; |
74c3cbe3 AV |
805 | int err; |
806 | ||
736f3203 | 807 | rule->tree = NULL; |
74c3cbe3 AV |
808 | list_for_each_entry(tree, &tree_list, list) { |
809 | if (!strcmp(seed->pathname, tree->pathname)) { | |
810 | put_tree(seed); | |
811 | rule->tree = tree; | |
812 | list_add(&rule->rlist, &tree->rules); | |
813 | return 0; | |
814 | } | |
815 | } | |
816 | tree = seed; | |
817 | list_add(&tree->list, &tree_list); | |
818 | list_add(&rule->rlist, &tree->rules); | |
819 | /* do not set rule->tree yet */ | |
820 | mutex_unlock(&audit_filter_mutex); | |
821 | ||
f1aaf262 IP |
822 | if (unlikely(!prune_thread)) { |
823 | err = audit_launch_prune(); | |
824 | if (err) | |
825 | goto Err; | |
826 | } | |
827 | ||
98bc993f | 828 | err = kern_path(tree->pathname, 0, &path); |
74c3cbe3 AV |
829 | if (err) |
830 | goto Err; | |
589ff870 | 831 | mnt = collect_mounts(&path); |
98bc993f | 832 | path_put(&path); |
be34d1a3 DH |
833 | if (IS_ERR(mnt)) { |
834 | err = PTR_ERR(mnt); | |
74c3cbe3 AV |
835 | goto Err; |
836 | } | |
74c3cbe3 AV |
837 | |
838 | get_tree(tree); | |
1f707137 | 839 | err = iterate_mounts(tag_mount, tree, mnt); |
74c3cbe3 AV |
840 | drop_collected_mounts(mnt); |
841 | ||
842 | if (!err) { | |
843 | struct node *node; | |
844 | spin_lock(&hash_lock); | |
845 | list_for_each_entry(node, &tree->chunks, list) | |
846 | node->index &= ~(1U<<31); | |
847 | spin_unlock(&hash_lock); | |
848 | } else { | |
849 | trim_marked(tree); | |
850 | goto Err; | |
851 | } | |
852 | ||
853 | mutex_lock(&audit_filter_mutex); | |
854 | if (list_empty(&rule->rlist)) { | |
855 | put_tree(tree); | |
856 | return -ENOENT; | |
857 | } | |
858 | rule->tree = tree; | |
859 | put_tree(tree); | |
860 | ||
861 | return 0; | |
862 | Err: | |
863 | mutex_lock(&audit_filter_mutex); | |
864 | list_del_init(&tree->list); | |
865 | list_del_init(&tree->rules); | |
866 | put_tree(tree); | |
867 | return err; | |
868 | } | |
869 | ||
870 | int audit_tag_tree(char *old, char *new) | |
871 | { | |
872 | struct list_head cursor, barrier; | |
873 | int failed = 0; | |
2096f759 | 874 | struct path path1, path2; |
74c3cbe3 | 875 | struct vfsmount *tagged; |
74c3cbe3 AV |
876 | int err; |
877 | ||
2096f759 | 878 | err = kern_path(new, 0, &path2); |
74c3cbe3 AV |
879 | if (err) |
880 | return err; | |
2096f759 AV |
881 | tagged = collect_mounts(&path2); |
882 | path_put(&path2); | |
be34d1a3 DH |
883 | if (IS_ERR(tagged)) |
884 | return PTR_ERR(tagged); | |
74c3cbe3 | 885 | |
2096f759 | 886 | err = kern_path(old, 0, &path1); |
74c3cbe3 AV |
887 | if (err) { |
888 | drop_collected_mounts(tagged); | |
889 | return err; | |
890 | } | |
74c3cbe3 | 891 | |
74c3cbe3 AV |
892 | mutex_lock(&audit_filter_mutex); |
893 | list_add(&barrier, &tree_list); | |
894 | list_add(&cursor, &barrier); | |
895 | ||
896 | while (cursor.next != &tree_list) { | |
897 | struct audit_tree *tree; | |
2096f759 | 898 | int good_one = 0; |
74c3cbe3 AV |
899 | |
900 | tree = container_of(cursor.next, struct audit_tree, list); | |
901 | get_tree(tree); | |
902 | list_del(&cursor); | |
903 | list_add(&cursor, &tree->list); | |
904 | mutex_unlock(&audit_filter_mutex); | |
905 | ||
2096f759 AV |
906 | err = kern_path(tree->pathname, 0, &path2); |
907 | if (!err) { | |
908 | good_one = path_is_under(&path1, &path2); | |
909 | path_put(&path2); | |
74c3cbe3 AV |
910 | } |
911 | ||
2096f759 | 912 | if (!good_one) { |
74c3cbe3 AV |
913 | put_tree(tree); |
914 | mutex_lock(&audit_filter_mutex); | |
915 | continue; | |
916 | } | |
74c3cbe3 | 917 | |
1f707137 | 918 | failed = iterate_mounts(tag_mount, tree, tagged); |
74c3cbe3 AV |
919 | if (failed) { |
920 | put_tree(tree); | |
921 | mutex_lock(&audit_filter_mutex); | |
922 | break; | |
923 | } | |
924 | ||
925 | mutex_lock(&audit_filter_mutex); | |
926 | spin_lock(&hash_lock); | |
927 | if (!tree->goner) { | |
928 | list_del(&tree->list); | |
929 | list_add(&tree->list, &tree_list); | |
930 | } | |
931 | spin_unlock(&hash_lock); | |
932 | put_tree(tree); | |
933 | } | |
934 | ||
935 | while (barrier.prev != &tree_list) { | |
936 | struct audit_tree *tree; | |
937 | ||
938 | tree = container_of(barrier.prev, struct audit_tree, list); | |
939 | get_tree(tree); | |
940 | list_del(&tree->list); | |
941 | list_add(&tree->list, &barrier); | |
942 | mutex_unlock(&audit_filter_mutex); | |
943 | ||
944 | if (!failed) { | |
945 | struct node *node; | |
946 | spin_lock(&hash_lock); | |
947 | list_for_each_entry(node, &tree->chunks, list) | |
948 | node->index &= ~(1U<<31); | |
949 | spin_unlock(&hash_lock); | |
950 | } else { | |
951 | trim_marked(tree); | |
952 | } | |
953 | ||
954 | put_tree(tree); | |
955 | mutex_lock(&audit_filter_mutex); | |
956 | } | |
957 | list_del(&barrier); | |
958 | list_del(&cursor); | |
74c3cbe3 | 959 | mutex_unlock(&audit_filter_mutex); |
2096f759 | 960 | path_put(&path1); |
74c3cbe3 AV |
961 | drop_collected_mounts(tagged); |
962 | return failed; | |
963 | } | |
964 | ||
916d7576 AV |
965 | |
966 | static void audit_schedule_prune(void) | |
967 | { | |
f1aaf262 | 968 | wake_up_process(prune_thread); |
916d7576 AV |
969 | } |
970 | ||
971 | /* | |
972 | * ... and that one is done if evict_chunk() decides to delay until the end | |
973 | * of syscall. Runs synchronously. | |
974 | */ | |
9e36a5d4 | 975 | void audit_kill_trees(struct audit_context *context) |
916d7576 | 976 | { |
9e36a5d4 RGB |
977 | struct list_head *list = &context->killed_trees; |
978 | ||
ce423631 | 979 | audit_ctl_lock(); |
916d7576 AV |
980 | mutex_lock(&audit_filter_mutex); |
981 | ||
982 | while (!list_empty(list)) { | |
983 | struct audit_tree *victim; | |
984 | ||
985 | victim = list_entry(list->next, struct audit_tree, list); | |
9e36a5d4 | 986 | kill_rules(context, victim); |
916d7576 AV |
987 | list_del_init(&victim->list); |
988 | ||
989 | mutex_unlock(&audit_filter_mutex); | |
990 | ||
991 | prune_one(victim); | |
992 | ||
993 | mutex_lock(&audit_filter_mutex); | |
994 | } | |
995 | ||
996 | mutex_unlock(&audit_filter_mutex); | |
ce423631 | 997 | audit_ctl_unlock(); |
74c3cbe3 AV |
998 | } |
999 | ||
1000 | /* | |
1001 | * Here comes the stuff asynchronous to auditctl operations | |
1002 | */ | |
1003 | ||
74c3cbe3 AV |
1004 | static void evict_chunk(struct audit_chunk *chunk) |
1005 | { | |
1006 | struct audit_tree *owner; | |
916d7576 AV |
1007 | struct list_head *postponed = audit_killed_trees(); |
1008 | int need_prune = 0; | |
74c3cbe3 AV |
1009 | int n; |
1010 | ||
74c3cbe3 AV |
1011 | mutex_lock(&audit_filter_mutex); |
1012 | spin_lock(&hash_lock); | |
1013 | while (!list_empty(&chunk->trees)) { | |
1014 | owner = list_entry(chunk->trees.next, | |
1015 | struct audit_tree, same_root); | |
1016 | owner->goner = 1; | |
1017 | owner->root = NULL; | |
1018 | list_del_init(&owner->same_root); | |
1019 | spin_unlock(&hash_lock); | |
916d7576 | 1020 | if (!postponed) { |
9e36a5d4 | 1021 | kill_rules(audit_context(), owner); |
916d7576 AV |
1022 | list_move(&owner->list, &prune_list); |
1023 | need_prune = 1; | |
1024 | } else { | |
1025 | list_move(&owner->list, postponed); | |
1026 | } | |
74c3cbe3 AV |
1027 | spin_lock(&hash_lock); |
1028 | } | |
1029 | list_del_rcu(&chunk->hash); | |
1030 | for (n = 0; n < chunk->count; n++) | |
1031 | list_del_init(&chunk->owners[n].list); | |
1032 | spin_unlock(&hash_lock); | |
f1aaf262 | 1033 | mutex_unlock(&audit_filter_mutex); |
916d7576 AV |
1034 | if (need_prune) |
1035 | audit_schedule_prune(); | |
74c3cbe3 AV |
1036 | } |
1037 | ||
b9a1b977 AG |
1038 | static int audit_tree_handle_event(struct fsnotify_mark *mark, u32 mask, |
1039 | struct inode *inode, struct inode *dir, | |
1040 | const struct qstr *file_name) | |
74c3cbe3 | 1041 | { |
83c4c4b0 | 1042 | return 0; |
28a3a7eb | 1043 | } |
74c3cbe3 | 1044 | |
f905c2fc JK |
1045 | static void audit_tree_freeing_mark(struct fsnotify_mark *mark, |
1046 | struct fsnotify_group *group) | |
28a3a7eb | 1047 | { |
83d23bc8 | 1048 | struct audit_chunk *chunk; |
28a3a7eb | 1049 | |
f905c2fc | 1050 | mutex_lock(&mark->group->mark_mutex); |
83d23bc8 | 1051 | spin_lock(&hash_lock); |
f905c2fc JK |
1052 | chunk = mark_chunk(mark); |
1053 | replace_mark_chunk(mark, NULL); | |
83d23bc8 | 1054 | spin_unlock(&hash_lock); |
f905c2fc | 1055 | mutex_unlock(&mark->group->mark_mutex); |
83d23bc8 JK |
1056 | if (chunk) { |
1057 | evict_chunk(chunk); | |
1058 | audit_mark_put_chunk(chunk); | |
1059 | } | |
b3e8692b MS |
1060 | |
1061 | /* | |
1062 | * We are guaranteed to have at least one reference to the mark from | |
1063 | * either the inode or the caller of fsnotify_destroy_mark(). | |
1064 | */ | |
f905c2fc | 1065 | BUG_ON(refcount_read(&mark->refcnt) < 1); |
74c3cbe3 AV |
1066 | } |
1067 | ||
28a3a7eb | 1068 | static const struct fsnotify_ops audit_tree_ops = { |
b9a1b977 | 1069 | .handle_inode_event = audit_tree_handle_event, |
28a3a7eb | 1070 | .freeing_mark = audit_tree_freeing_mark, |
054c636e | 1071 | .free_mark = audit_tree_destroy_watch, |
74c3cbe3 AV |
1072 | }; |
1073 | ||
1074 | static int __init audit_tree_init(void) | |
1075 | { | |
1076 | int i; | |
1077 | ||
5f516130 JK |
1078 | audit_tree_mark_cachep = KMEM_CACHE(audit_tree_mark, SLAB_PANIC); |
1079 | ||
0d2e2a1d | 1080 | audit_tree_group = fsnotify_alloc_group(&audit_tree_ops); |
28a3a7eb EP |
1081 | if (IS_ERR(audit_tree_group)) |
1082 | audit_panic("cannot initialize fsnotify group for rectree watches"); | |
74c3cbe3 AV |
1083 | |
1084 | for (i = 0; i < HASH_SIZE; i++) | |
1085 | INIT_LIST_HEAD(&chunk_hash_heads[i]); | |
1086 | ||
1087 | return 0; | |
1088 | } | |
1089 | __initcall(audit_tree_init); |