Commit | Line | Data |
---|---|---|
847b173e TH |
1 | /* |
2 | * security/tomoyo/gc.c | |
3 | * | |
0f2a55d5 | 4 | * Copyright (C) 2005-2011 NTT DATA CORPORATION |
847b173e TH |
5 | */ |
6 | ||
7 | #include "common.h" | |
8 | #include <linux/kthread.h> | |
5a0e3ad6 | 9 | #include <linux/slab.h> |
847b173e | 10 | |
a427fd14 TH |
11 | /** |
12 | * tomoyo_memory_free - Free memory for elements. | |
13 | * | |
14 | * @ptr: Pointer to allocated memory. | |
15 | * | |
16 | * Returns nothing. | |
17 | * | |
18 | * Caller holds tomoyo_policy_lock mutex. | |
19 | */ | |
20 | static inline void tomoyo_memory_free(void *ptr) | |
21 | { | |
22 | tomoyo_memory_used[TOMOYO_MEMORY_POLICY] -= ksize(ptr); | |
23 | kfree(ptr); | |
24 | } | |
25 | ||
2e503bbb TH |
26 | /* The list for "struct tomoyo_io_buffer". */ |
27 | static LIST_HEAD(tomoyo_io_buffer_list); | |
28 | /* Lock for protecting tomoyo_io_buffer_list. */ | |
29 | static DEFINE_SPINLOCK(tomoyo_io_buffer_list_lock); | |
30 | ||
2e503bbb TH |
31 | /** |
32 | * tomoyo_struct_used_by_io_buffer - Check whether the list element is used by /sys/kernel/security/tomoyo/ users or not. | |
33 | * | |
34 | * @element: Pointer to "struct list_head". | |
35 | * | |
36 | * Returns true if @element is used by /sys/kernel/security/tomoyo/ users, | |
37 | * false otherwise. | |
38 | */ | |
39 | static bool tomoyo_struct_used_by_io_buffer(const struct list_head *element) | |
40 | { | |
41 | struct tomoyo_io_buffer *head; | |
42 | bool in_use = false; | |
43 | ||
44 | spin_lock(&tomoyo_io_buffer_list_lock); | |
45 | list_for_each_entry(head, &tomoyo_io_buffer_list, list) { | |
46 | head->users++; | |
47 | spin_unlock(&tomoyo_io_buffer_list_lock); | |
f9732ea1 | 48 | mutex_lock(&head->io_sem); |
2e503bbb TH |
49 | if (head->r.domain == element || head->r.group == element || |
50 | head->r.acl == element || &head->w.domain->list == element) | |
51 | in_use = true; | |
52 | mutex_unlock(&head->io_sem); | |
2e503bbb TH |
53 | spin_lock(&tomoyo_io_buffer_list_lock); |
54 | head->users--; | |
55 | if (in_use) | |
56 | break; | |
57 | } | |
58 | spin_unlock(&tomoyo_io_buffer_list_lock); | |
59 | return in_use; | |
60 | } | |
61 | ||
62 | /** | |
63 | * tomoyo_name_used_by_io_buffer - Check whether the string is used by /sys/kernel/security/tomoyo/ users or not. | |
64 | * | |
65 | * @string: String to check. | |
2e503bbb TH |
66 | * |
67 | * Returns true if @string is used by /sys/kernel/security/tomoyo/ users, | |
68 | * false otherwise. | |
69 | */ | |
f9732ea1 | 70 | static bool tomoyo_name_used_by_io_buffer(const char *string) |
2e503bbb TH |
71 | { |
72 | struct tomoyo_io_buffer *head; | |
f9732ea1 | 73 | const size_t size = strlen(string) + 1; |
2e503bbb TH |
74 | bool in_use = false; |
75 | ||
76 | spin_lock(&tomoyo_io_buffer_list_lock); | |
77 | list_for_each_entry(head, &tomoyo_io_buffer_list, list) { | |
78 | int i; | |
79 | head->users++; | |
80 | spin_unlock(&tomoyo_io_buffer_list_lock); | |
f9732ea1 | 81 | mutex_lock(&head->io_sem); |
2e503bbb TH |
82 | for (i = 0; i < TOMOYO_MAX_IO_READ_QUEUE; i++) { |
83 | const char *w = head->r.w[i]; | |
84 | if (w < string || w > string + size) | |
85 | continue; | |
86 | in_use = true; | |
87 | break; | |
88 | } | |
89 | mutex_unlock(&head->io_sem); | |
2e503bbb TH |
90 | spin_lock(&tomoyo_io_buffer_list_lock); |
91 | head->users--; | |
92 | if (in_use) | |
93 | break; | |
94 | } | |
95 | spin_unlock(&tomoyo_io_buffer_list_lock); | |
96 | return in_use; | |
97 | } | |
98 | ||
0df7e8b8 TH |
99 | /** |
100 | * tomoyo_del_transition_control - Delete members in "struct tomoyo_transition_control". | |
101 | * | |
102 | * @element: Pointer to "struct list_head". | |
103 | * | |
104 | * Returns nothing. | |
105 | */ | |
f9732ea1 | 106 | static inline void tomoyo_del_transition_control(struct list_head *element) |
847b173e | 107 | { |
5448ec4f | 108 | struct tomoyo_transition_control *ptr = |
e79acf0e | 109 | container_of(element, typeof(*ptr), head.list); |
847b173e TH |
110 | tomoyo_put_name(ptr->domainname); |
111 | tomoyo_put_name(ptr->program); | |
112 | } | |
113 | ||
0df7e8b8 TH |
114 | /** |
115 | * tomoyo_del_aggregator - Delete members in "struct tomoyo_aggregator". | |
116 | * | |
117 | * @element: Pointer to "struct list_head". | |
118 | * | |
119 | * Returns nothing. | |
120 | */ | |
f9732ea1 | 121 | static inline void tomoyo_del_aggregator(struct list_head *element) |
1084307c | 122 | { |
e2bf6907 | 123 | struct tomoyo_aggregator *ptr = |
e79acf0e | 124 | container_of(element, typeof(*ptr), head.list); |
1084307c TH |
125 | tomoyo_put_name(ptr->original_name); |
126 | tomoyo_put_name(ptr->aggregated_name); | |
127 | } | |
128 | ||
0df7e8b8 TH |
129 | /** |
130 | * tomoyo_del_manager - Delete members in "struct tomoyo_manager". | |
131 | * | |
132 | * @element: Pointer to "struct list_head". | |
133 | * | |
134 | * Returns nothing. | |
135 | */ | |
f9732ea1 | 136 | static inline void tomoyo_del_manager(struct list_head *element) |
847b173e | 137 | { |
e2bf6907 | 138 | struct tomoyo_manager *ptr = |
e79acf0e | 139 | container_of(element, typeof(*ptr), head.list); |
847b173e TH |
140 | tomoyo_put_name(ptr->manager); |
141 | } | |
142 | ||
0df7e8b8 TH |
143 | /** |
144 | * tomoyo_del_acl - Delete members in "struct tomoyo_acl_info". | |
145 | * | |
146 | * @element: Pointer to "struct list_head". | |
147 | * | |
148 | * Returns nothing. | |
149 | */ | |
e79acf0e | 150 | static void tomoyo_del_acl(struct list_head *element) |
847b173e | 151 | { |
e79acf0e TH |
152 | struct tomoyo_acl_info *acl = |
153 | container_of(element, typeof(*acl), list); | |
2066a361 | 154 | tomoyo_put_condition(acl->cond); |
847b173e | 155 | switch (acl->type) { |
7ef61233 | 156 | case TOMOYO_TYPE_PATH_ACL: |
847b173e | 157 | { |
7ef61233 | 158 | struct tomoyo_path_acl *entry |
847b173e | 159 | = container_of(acl, typeof(*entry), head); |
7762fbff | 160 | tomoyo_put_name_union(&entry->name); |
847b173e TH |
161 | } |
162 | break; | |
7ef61233 | 163 | case TOMOYO_TYPE_PATH2_ACL: |
847b173e | 164 | { |
7ef61233 | 165 | struct tomoyo_path2_acl *entry |
847b173e | 166 | = container_of(acl, typeof(*entry), head); |
7762fbff TH |
167 | tomoyo_put_name_union(&entry->name1); |
168 | tomoyo_put_name_union(&entry->name2); | |
847b173e TH |
169 | } |
170 | break; | |
a1f9bb6a TH |
171 | case TOMOYO_TYPE_PATH_NUMBER_ACL: |
172 | { | |
173 | struct tomoyo_path_number_acl *entry | |
174 | = container_of(acl, typeof(*entry), head); | |
175 | tomoyo_put_name_union(&entry->name); | |
176 | tomoyo_put_number_union(&entry->number); | |
177 | } | |
178 | break; | |
75093152 | 179 | case TOMOYO_TYPE_MKDEV_ACL: |
a1f9bb6a | 180 | { |
75093152 | 181 | struct tomoyo_mkdev_acl *entry |
a1f9bb6a TH |
182 | = container_of(acl, typeof(*entry), head); |
183 | tomoyo_put_name_union(&entry->name); | |
184 | tomoyo_put_number_union(&entry->mode); | |
185 | tomoyo_put_number_union(&entry->major); | |
186 | tomoyo_put_number_union(&entry->minor); | |
187 | } | |
188 | break; | |
2106ccd9 TH |
189 | case TOMOYO_TYPE_MOUNT_ACL: |
190 | { | |
191 | struct tomoyo_mount_acl *entry | |
192 | = container_of(acl, typeof(*entry), head); | |
193 | tomoyo_put_name_union(&entry->dev_name); | |
194 | tomoyo_put_name_union(&entry->dir_name); | |
195 | tomoyo_put_name_union(&entry->fs_type); | |
196 | tomoyo_put_number_union(&entry->flags); | |
197 | } | |
198 | break; | |
d58e0da8 TH |
199 | case TOMOYO_TYPE_ENV_ACL: |
200 | { | |
201 | struct tomoyo_env_acl *entry = | |
202 | container_of(acl, typeof(*entry), head); | |
203 | ||
204 | tomoyo_put_name(entry->env); | |
205 | } | |
206 | break; | |
059d84db TH |
207 | case TOMOYO_TYPE_INET_ACL: |
208 | { | |
209 | struct tomoyo_inet_acl *entry = | |
210 | container_of(acl, typeof(*entry), head); | |
211 | ||
212 | tomoyo_put_group(entry->address.group); | |
213 | tomoyo_put_number_union(&entry->port); | |
214 | } | |
215 | break; | |
216 | case TOMOYO_TYPE_UNIX_ACL: | |
217 | { | |
218 | struct tomoyo_unix_acl *entry = | |
219 | container_of(acl, typeof(*entry), head); | |
220 | ||
221 | tomoyo_put_name_union(&entry->name); | |
222 | } | |
223 | break; | |
545a7260 TH |
224 | case TOMOYO_TYPE_MANUAL_TASK_ACL: |
225 | { | |
226 | struct tomoyo_task_acl *entry = | |
227 | container_of(acl, typeof(*entry), head); | |
228 | tomoyo_put_name(entry->domainname); | |
229 | } | |
230 | break; | |
847b173e TH |
231 | } |
232 | } | |
233 | ||
2e503bbb TH |
234 | /** |
235 | * tomoyo_del_domain - Delete members in "struct tomoyo_domain_info". | |
236 | * | |
237 | * @element: Pointer to "struct list_head". | |
238 | * | |
f9732ea1 | 239 | * Returns nothing. |
a427fd14 TH |
240 | * |
241 | * Caller holds tomoyo_policy_lock mutex. | |
2e503bbb | 242 | */ |
f9732ea1 | 243 | static inline void tomoyo_del_domain(struct list_head *element) |
847b173e | 244 | { |
e79acf0e TH |
245 | struct tomoyo_domain_info *domain = |
246 | container_of(element, typeof(*domain), list); | |
847b173e TH |
247 | struct tomoyo_acl_info *acl; |
248 | struct tomoyo_acl_info *tmp; | |
249 | /* | |
f9732ea1 TH |
250 | * Since this domain is referenced from neither |
251 | * "struct tomoyo_io_buffer" nor "struct cred"->security, we can delete | |
252 | * elements without checking for is_deleted flag. | |
847b173e | 253 | */ |
847b173e | 254 | list_for_each_entry_safe(acl, tmp, &domain->acl_info_list, list) { |
e79acf0e | 255 | tomoyo_del_acl(&acl->list); |
847b173e TH |
256 | tomoyo_memory_free(acl); |
257 | } | |
258 | tomoyo_put_name(domain->domainname); | |
847b173e TH |
259 | } |
260 | ||
2066a361 TH |
261 | /** |
262 | * tomoyo_del_condition - Delete members in "struct tomoyo_condition". | |
263 | * | |
264 | * @element: Pointer to "struct list_head". | |
265 | * | |
266 | * Returns nothing. | |
267 | */ | |
268 | void tomoyo_del_condition(struct list_head *element) | |
269 | { | |
270 | struct tomoyo_condition *cond = container_of(element, typeof(*cond), | |
271 | head.list); | |
272 | const u16 condc = cond->condc; | |
273 | const u16 numbers_count = cond->numbers_count; | |
2ca9bf45 | 274 | const u16 names_count = cond->names_count; |
5b636857 TH |
275 | const u16 argc = cond->argc; |
276 | const u16 envc = cond->envc; | |
2066a361 TH |
277 | unsigned int i; |
278 | const struct tomoyo_condition_element *condp | |
279 | = (const struct tomoyo_condition_element *) (cond + 1); | |
280 | struct tomoyo_number_union *numbers_p | |
281 | = (struct tomoyo_number_union *) (condp + condc); | |
2ca9bf45 TH |
282 | struct tomoyo_name_union *names_p |
283 | = (struct tomoyo_name_union *) (numbers_p + numbers_count); | |
5b636857 TH |
284 | const struct tomoyo_argv *argv |
285 | = (const struct tomoyo_argv *) (names_p + names_count); | |
286 | const struct tomoyo_envp *envp | |
287 | = (const struct tomoyo_envp *) (argv + argc); | |
2066a361 TH |
288 | for (i = 0; i < numbers_count; i++) |
289 | tomoyo_put_number_union(numbers_p++); | |
2ca9bf45 TH |
290 | for (i = 0; i < names_count; i++) |
291 | tomoyo_put_name_union(names_p++); | |
5b636857 TH |
292 | for (i = 0; i < argc; argv++, i++) |
293 | tomoyo_put_name(argv->value); | |
294 | for (i = 0; i < envc; envp++, i++) { | |
295 | tomoyo_put_name(envp->name); | |
296 | tomoyo_put_name(envp->value); | |
297 | } | |
2066a361 | 298 | } |
847b173e | 299 | |
0df7e8b8 TH |
300 | /** |
301 | * tomoyo_del_name - Delete members in "struct tomoyo_name". | |
302 | * | |
303 | * @element: Pointer to "struct list_head". | |
304 | * | |
305 | * Returns nothing. | |
306 | */ | |
f9732ea1 | 307 | static inline void tomoyo_del_name(struct list_head *element) |
847b173e | 308 | { |
f9732ea1 | 309 | /* Nothing to do. */ |
847b173e TH |
310 | } |
311 | ||
0df7e8b8 TH |
312 | /** |
313 | * tomoyo_del_path_group - Delete members in "struct tomoyo_path_group". | |
314 | * | |
315 | * @element: Pointer to "struct list_head". | |
316 | * | |
317 | * Returns nothing. | |
318 | */ | |
f9732ea1 | 319 | static inline void tomoyo_del_path_group(struct list_head *element) |
7762fbff | 320 | { |
a98aa4de | 321 | struct tomoyo_path_group *member = |
e79acf0e | 322 | container_of(element, typeof(*member), head.list); |
7762fbff TH |
323 | tomoyo_put_name(member->member_name); |
324 | } | |
325 | ||
0df7e8b8 TH |
326 | /** |
327 | * tomoyo_del_group - Delete "struct tomoyo_group". | |
328 | * | |
329 | * @element: Pointer to "struct list_head". | |
330 | * | |
331 | * Returns nothing. | |
332 | */ | |
f9732ea1 | 333 | static inline void tomoyo_del_group(struct list_head *element) |
7762fbff | 334 | { |
a98aa4de | 335 | struct tomoyo_group *group = |
0df7e8b8 | 336 | container_of(element, typeof(*group), head.list); |
7762fbff TH |
337 | tomoyo_put_name(group->group_name); |
338 | } | |
339 | ||
059d84db TH |
340 | /** |
341 | * tomoyo_del_address_group - Delete members in "struct tomoyo_address_group". | |
342 | * | |
343 | * @element: Pointer to "struct list_head". | |
344 | * | |
345 | * Returns nothing. | |
346 | */ | |
347 | static inline void tomoyo_del_address_group(struct list_head *element) | |
348 | { | |
349 | /* Nothing to do. */ | |
350 | } | |
351 | ||
0df7e8b8 TH |
352 | /** |
353 | * tomoyo_del_number_group - Delete members in "struct tomoyo_number_group". | |
354 | * | |
355 | * @element: Pointer to "struct list_head". | |
356 | * | |
357 | * Returns nothing. | |
358 | */ | |
f9732ea1 | 359 | static inline void tomoyo_del_number_group(struct list_head *element) |
4c3e9e2d | 360 | { |
f9732ea1 TH |
361 | /* Nothing to do. */ |
362 | } | |
363 | ||
364 | /** | |
365 | * tomoyo_try_to_gc - Try to kfree() an entry. | |
366 | * | |
367 | * @type: One of values in "enum tomoyo_policy_id". | |
368 | * @element: Pointer to "struct list_head". | |
369 | * | |
370 | * Returns nothing. | |
371 | * | |
372 | * Caller holds tomoyo_policy_lock mutex. | |
373 | */ | |
374 | static void tomoyo_try_to_gc(const enum tomoyo_policy_id type, | |
375 | struct list_head *element) | |
376 | { | |
377 | /* | |
378 | * __list_del_entry() guarantees that the list element became no longer | |
379 | * reachable from the list which the element was originally on (e.g. | |
380 | * tomoyo_domain_list). Also, synchronize_srcu() guarantees that the | |
381 | * list element became no longer referenced by syscall users. | |
382 | */ | |
383 | __list_del_entry(element); | |
384 | mutex_unlock(&tomoyo_policy_lock); | |
385 | synchronize_srcu(&tomoyo_ss); | |
386 | /* | |
387 | * However, there are two users which may still be using the list | |
388 | * element. We need to defer until both users forget this element. | |
389 | * | |
390 | * Don't kfree() until "struct tomoyo_io_buffer"->r.{domain,group,acl} | |
391 | * and "struct tomoyo_io_buffer"->w.domain forget this element. | |
392 | */ | |
393 | if (tomoyo_struct_used_by_io_buffer(element)) | |
394 | goto reinject; | |
395 | switch (type) { | |
396 | case TOMOYO_ID_TRANSITION_CONTROL: | |
397 | tomoyo_del_transition_control(element); | |
398 | break; | |
399 | case TOMOYO_ID_MANAGER: | |
400 | tomoyo_del_manager(element); | |
401 | break; | |
402 | case TOMOYO_ID_AGGREGATOR: | |
403 | tomoyo_del_aggregator(element); | |
404 | break; | |
405 | case TOMOYO_ID_GROUP: | |
406 | tomoyo_del_group(element); | |
407 | break; | |
408 | case TOMOYO_ID_PATH_GROUP: | |
409 | tomoyo_del_path_group(element); | |
410 | break; | |
411 | case TOMOYO_ID_ADDRESS_GROUP: | |
412 | tomoyo_del_address_group(element); | |
413 | break; | |
414 | case TOMOYO_ID_NUMBER_GROUP: | |
415 | tomoyo_del_number_group(element); | |
416 | break; | |
417 | case TOMOYO_ID_CONDITION: | |
418 | tomoyo_del_condition(element); | |
419 | break; | |
420 | case TOMOYO_ID_NAME: | |
421 | /* | |
422 | * Don't kfree() until all "struct tomoyo_io_buffer"->r.w[] | |
423 | * forget this element. | |
424 | */ | |
425 | if (tomoyo_name_used_by_io_buffer | |
426 | (container_of(element, typeof(struct tomoyo_name), | |
427 | head.list)->entry.name)) | |
428 | goto reinject; | |
429 | tomoyo_del_name(element); | |
430 | break; | |
431 | case TOMOYO_ID_ACL: | |
432 | tomoyo_del_acl(element); | |
433 | break; | |
434 | case TOMOYO_ID_DOMAIN: | |
435 | /* | |
436 | * Don't kfree() until all "struct cred"->security forget this | |
437 | * element. | |
438 | */ | |
439 | if (atomic_read(&container_of | |
440 | (element, typeof(struct tomoyo_domain_info), | |
441 | list)->users)) | |
442 | goto reinject; | |
f9732ea1 TH |
443 | break; |
444 | case TOMOYO_MAX_POLICY: | |
445 | break; | |
446 | } | |
447 | mutex_lock(&tomoyo_policy_lock); | |
a427fd14 TH |
448 | if (type == TOMOYO_ID_DOMAIN) |
449 | tomoyo_del_domain(element); | |
f9732ea1 TH |
450 | tomoyo_memory_free(element); |
451 | return; | |
452 | reinject: | |
453 | /* | |
454 | * We can safely reinject this element here bacause | |
455 | * (1) Appending list elements and removing list elements are protected | |
456 | * by tomoyo_policy_lock mutex. | |
457 | * (2) Only this function removes list elements and this function is | |
458 | * exclusively executed by tomoyo_gc_mutex mutex. | |
459 | * are true. | |
460 | */ | |
461 | mutex_lock(&tomoyo_policy_lock); | |
462 | list_add_rcu(element, element->prev); | |
4c3e9e2d TH |
463 | } |
464 | ||
0df7e8b8 TH |
465 | /** |
466 | * tomoyo_collect_member - Delete elements with "struct tomoyo_acl_head". | |
467 | * | |
468 | * @id: One of values in "enum tomoyo_policy_id". | |
469 | * @member_list: Pointer to "struct list_head". | |
470 | * | |
f9732ea1 | 471 | * Returns nothing. |
0df7e8b8 | 472 | */ |
f9732ea1 | 473 | static void tomoyo_collect_member(const enum tomoyo_policy_id id, |
0df7e8b8 | 474 | struct list_head *member_list) |
d2f8b234 TH |
475 | { |
476 | struct tomoyo_acl_head *member; | |
f9732ea1 TH |
477 | struct tomoyo_acl_head *tmp; |
478 | list_for_each_entry_safe(member, tmp, member_list, list) { | |
d2f8b234 TH |
479 | if (!member->is_deleted) |
480 | continue; | |
f9732ea1 TH |
481 | member->is_deleted = TOMOYO_GC_IN_PROGRESS; |
482 | tomoyo_try_to_gc(id, &member->list); | |
d2f8b234 | 483 | } |
d2f8b234 TH |
484 | } |
485 | ||
32997144 TH |
486 | /** |
487 | * tomoyo_collect_acl - Delete elements in "struct tomoyo_domain_info". | |
488 | * | |
489 | * @list: Pointer to "struct list_head". | |
490 | * | |
f9732ea1 | 491 | * Returns nothing. |
32997144 | 492 | */ |
f9732ea1 | 493 | static void tomoyo_collect_acl(struct list_head *list) |
d2f8b234 TH |
494 | { |
495 | struct tomoyo_acl_info *acl; | |
f9732ea1 TH |
496 | struct tomoyo_acl_info *tmp; |
497 | list_for_each_entry_safe(acl, tmp, list, list) { | |
d2f8b234 TH |
498 | if (!acl->is_deleted) |
499 | continue; | |
f9732ea1 TH |
500 | acl->is_deleted = TOMOYO_GC_IN_PROGRESS; |
501 | tomoyo_try_to_gc(TOMOYO_ID_ACL, &acl->list); | |
d2f8b234 | 502 | } |
d2f8b234 TH |
503 | } |
504 | ||
0df7e8b8 | 505 | /** |
f9732ea1 | 506 | * tomoyo_collect_entry - Try to kfree() deleted elements. |
0df7e8b8 TH |
507 | * |
508 | * Returns nothing. | |
509 | */ | |
847b173e TH |
510 | static void tomoyo_collect_entry(void) |
511 | { | |
d2f8b234 | 512 | int i; |
bd03a3e4 TH |
513 | enum tomoyo_policy_id id; |
514 | struct tomoyo_policy_namespace *ns; | |
f9732ea1 | 515 | mutex_lock(&tomoyo_policy_lock); |
847b173e TH |
516 | { |
517 | struct tomoyo_domain_info *domain; | |
f9732ea1 TH |
518 | struct tomoyo_domain_info *tmp; |
519 | list_for_each_entry_safe(domain, tmp, &tomoyo_domain_list, | |
520 | list) { | |
521 | tomoyo_collect_acl(&domain->acl_info_list); | |
847b173e TH |
522 | if (!domain->is_deleted || atomic_read(&domain->users)) |
523 | continue; | |
f9732ea1 | 524 | tomoyo_try_to_gc(TOMOYO_ID_DOMAIN, &domain->list); |
847b173e TH |
525 | } |
526 | } | |
f9732ea1 | 527 | list_for_each_entry(ns, &tomoyo_namespace_list, namespace_list) { |
bd03a3e4 | 528 | for (id = 0; id < TOMOYO_MAX_POLICY; id++) |
f9732ea1 | 529 | tomoyo_collect_member(id, &ns->policy_list[id]); |
bd03a3e4 | 530 | for (i = 0; i < TOMOYO_MAX_ACL_GROUPS; i++) |
f9732ea1 TH |
531 | tomoyo_collect_acl(&ns->acl_group[i]); |
532 | } | |
533 | { | |
534 | struct tomoyo_shared_acl_head *ptr; | |
535 | struct tomoyo_shared_acl_head *tmp; | |
536 | list_for_each_entry_safe(ptr, tmp, &tomoyo_condition_list, | |
537 | list) { | |
538 | if (atomic_read(&ptr->users) > 0) | |
539 | continue; | |
540 | atomic_set(&ptr->users, TOMOYO_GC_IN_PROGRESS); | |
541 | tomoyo_try_to_gc(TOMOYO_ID_CONDITION, &ptr->list); | |
542 | } | |
543 | } | |
544 | list_for_each_entry(ns, &tomoyo_namespace_list, namespace_list) { | |
bd03a3e4 TH |
545 | for (i = 0; i < TOMOYO_MAX_GROUP; i++) { |
546 | struct list_head *list = &ns->group_list[i]; | |
547 | struct tomoyo_group *group; | |
f9732ea1 | 548 | struct tomoyo_group *tmp; |
bd03a3e4 TH |
549 | switch (i) { |
550 | case 0: | |
551 | id = TOMOYO_ID_PATH_GROUP; | |
552 | break; | |
059d84db | 553 | case 1: |
bd03a3e4 TH |
554 | id = TOMOYO_ID_NUMBER_GROUP; |
555 | break; | |
059d84db TH |
556 | default: |
557 | id = TOMOYO_ID_ADDRESS_GROUP; | |
558 | break; | |
bd03a3e4 | 559 | } |
f9732ea1 TH |
560 | list_for_each_entry_safe(group, tmp, list, head.list) { |
561 | tomoyo_collect_member(id, &group->member_list); | |
bd03a3e4 | 562 | if (!list_empty(&group->member_list) || |
f9732ea1 | 563 | atomic_read(&group->head.users) > 0) |
bd03a3e4 | 564 | continue; |
f9732ea1 TH |
565 | atomic_set(&group->head.users, |
566 | TOMOYO_GC_IN_PROGRESS); | |
567 | tomoyo_try_to_gc(TOMOYO_ID_GROUP, | |
568 | &group->head.list); | |
bd03a3e4 | 569 | } |
847b173e TH |
570 | } |
571 | } | |
f9732ea1 TH |
572 | for (i = 0; i < TOMOYO_MAX_HASH; i++) { |
573 | struct list_head *list = &tomoyo_name_list[i]; | |
bd03a3e4 | 574 | struct tomoyo_shared_acl_head *ptr; |
f9732ea1 TH |
575 | struct tomoyo_shared_acl_head *tmp; |
576 | list_for_each_entry_safe(ptr, tmp, list, list) { | |
577 | if (atomic_read(&ptr->users) > 0) | |
4c3e9e2d | 578 | continue; |
f9732ea1 TH |
579 | atomic_set(&ptr->users, TOMOYO_GC_IN_PROGRESS); |
580 | tomoyo_try_to_gc(TOMOYO_ID_NAME, &ptr->list); | |
4c3e9e2d TH |
581 | } |
582 | } | |
29282381 | 583 | mutex_unlock(&tomoyo_policy_lock); |
847b173e TH |
584 | } |
585 | ||
0df7e8b8 TH |
586 | /** |
587 | * tomoyo_gc_thread - Garbage collector thread function. | |
588 | * | |
589 | * @unused: Unused. | |
590 | * | |
0df7e8b8 TH |
591 | * Returns 0. |
592 | */ | |
847b173e TH |
593 | static int tomoyo_gc_thread(void *unused) |
594 | { | |
2e503bbb TH |
595 | /* Garbage collector thread is exclusive. */ |
596 | static DEFINE_MUTEX(tomoyo_gc_mutex); | |
597 | if (!mutex_trylock(&tomoyo_gc_mutex)) | |
598 | goto out; | |
f9732ea1 | 599 | tomoyo_collect_entry(); |
2e503bbb TH |
600 | { |
601 | struct tomoyo_io_buffer *head; | |
602 | struct tomoyo_io_buffer *tmp; | |
603 | ||
604 | spin_lock(&tomoyo_io_buffer_list_lock); | |
605 | list_for_each_entry_safe(head, tmp, &tomoyo_io_buffer_list, | |
606 | list) { | |
607 | if (head->users) | |
608 | continue; | |
609 | list_del(&head->list); | |
610 | kfree(head->read_buf); | |
611 | kfree(head->write_buf); | |
612 | kfree(head); | |
847b173e | 613 | } |
2e503bbb | 614 | spin_unlock(&tomoyo_io_buffer_list_lock); |
847b173e | 615 | } |
2e503bbb TH |
616 | mutex_unlock(&tomoyo_gc_mutex); |
617 | out: | |
618 | /* This acts as do_exit(0). */ | |
619 | return 0; | |
847b173e TH |
620 | } |
621 | ||
2e503bbb TH |
622 | /** |
623 | * tomoyo_notify_gc - Register/unregister /sys/kernel/security/tomoyo/ users. | |
624 | * | |
625 | * @head: Pointer to "struct tomoyo_io_buffer". | |
626 | * @is_register: True if register, false if unregister. | |
627 | * | |
628 | * Returns nothing. | |
629 | */ | |
630 | void tomoyo_notify_gc(struct tomoyo_io_buffer *head, const bool is_register) | |
847b173e | 631 | { |
2e503bbb TH |
632 | bool is_write = false; |
633 | ||
634 | spin_lock(&tomoyo_io_buffer_list_lock); | |
635 | if (is_register) { | |
636 | head->users = 1; | |
637 | list_add(&head->list, &tomoyo_io_buffer_list); | |
638 | } else { | |
639 | is_write = head->write_buf != NULL; | |
640 | if (!--head->users) { | |
641 | list_del(&head->list); | |
642 | kfree(head->read_buf); | |
643 | kfree(head->write_buf); | |
644 | kfree(head); | |
645 | } | |
646 | } | |
647 | spin_unlock(&tomoyo_io_buffer_list_lock); | |
648 | if (is_write) { | |
649 | struct task_struct *task = kthread_create(tomoyo_gc_thread, | |
650 | NULL, | |
651 | "GC for TOMOYO"); | |
652 | if (!IS_ERR(task)) | |
653 | wake_up_process(task); | |
654 | } | |
847b173e | 655 | } |