Commit | Line | Data |
---|---|---|
69664cf1 | 1 | /* Keyring handling |
1da177e4 | 2 | * |
69664cf1 | 3 | * Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved. |
1da177e4 LT |
4 | * Written by David Howells (dhowells@redhat.com) |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | */ | |
11 | ||
12 | #include <linux/module.h> | |
13 | #include <linux/init.h> | |
14 | #include <linux/sched.h> | |
15 | #include <linux/slab.h> | |
29db9190 | 16 | #include <linux/security.h> |
1da177e4 LT |
17 | #include <linux/seq_file.h> |
18 | #include <linux/err.h> | |
e9e349b0 | 19 | #include <keys/keyring-type.h> |
512ea3bc | 20 | #include <linux/uaccess.h> |
1da177e4 LT |
21 | #include "internal.h" |
22 | ||
f0641cba DH |
23 | #define rcu_dereference_locked_keyring(keyring) \ |
24 | (rcu_dereference_protected( \ | |
25 | (keyring)->payload.subscriptions, \ | |
26 | rwsem_is_locked((struct rw_semaphore *)&(keyring)->sem))) | |
27 | ||
1da177e4 LT |
28 | /* |
29 | * when plumbing the depths of the key tree, this sets a hard limit set on how | |
30 | * deep we're willing to go | |
31 | */ | |
32 | #define KEYRING_SEARCH_MAX_DEPTH 6 | |
33 | ||
34 | /* | |
35 | * we keep all named keyrings in a hash to speed looking them up | |
36 | */ | |
37 | #define KEYRING_NAME_HASH_SIZE (1 << 5) | |
38 | ||
39 | static struct list_head keyring_name_hash[KEYRING_NAME_HASH_SIZE]; | |
40 | static DEFINE_RWLOCK(keyring_name_lock); | |
41 | ||
42 | static inline unsigned keyring_hash(const char *desc) | |
43 | { | |
44 | unsigned bucket = 0; | |
45 | ||
46 | for (; *desc; desc++) | |
c5b60b5e | 47 | bucket += (unsigned char)*desc; |
1da177e4 LT |
48 | |
49 | return bucket & (KEYRING_NAME_HASH_SIZE - 1); | |
50 | } | |
51 | ||
52 | /* | |
53 | * the keyring type definition | |
54 | */ | |
55 | static int keyring_instantiate(struct key *keyring, | |
56 | const void *data, size_t datalen); | |
1da177e4 | 57 | static int keyring_match(const struct key *keyring, const void *criterion); |
31204ed9 | 58 | static void keyring_revoke(struct key *keyring); |
1da177e4 LT |
59 | static void keyring_destroy(struct key *keyring); |
60 | static void keyring_describe(const struct key *keyring, struct seq_file *m); | |
61 | static long keyring_read(const struct key *keyring, | |
62 | char __user *buffer, size_t buflen); | |
63 | ||
64 | struct key_type key_type_keyring = { | |
65 | .name = "keyring", | |
66 | .def_datalen = sizeof(struct keyring_list), | |
67 | .instantiate = keyring_instantiate, | |
1da177e4 | 68 | .match = keyring_match, |
31204ed9 | 69 | .revoke = keyring_revoke, |
1da177e4 LT |
70 | .destroy = keyring_destroy, |
71 | .describe = keyring_describe, | |
72 | .read = keyring_read, | |
73 | }; | |
74 | ||
7318226e DH |
75 | EXPORT_SYMBOL(key_type_keyring); |
76 | ||
1da177e4 LT |
77 | /* |
78 | * semaphore to serialise link/link calls to prevent two link calls in parallel | |
79 | * introducing a cycle | |
80 | */ | |
1ae8f407 | 81 | static DECLARE_RWSEM(keyring_serialise_link_sem); |
1da177e4 LT |
82 | |
83 | /*****************************************************************************/ | |
84 | /* | |
85 | * publish the name of a keyring so that it can be found by name (if it has | |
86 | * one) | |
87 | */ | |
69664cf1 | 88 | static void keyring_publish_name(struct key *keyring) |
1da177e4 LT |
89 | { |
90 | int bucket; | |
91 | ||
92 | if (keyring->description) { | |
93 | bucket = keyring_hash(keyring->description); | |
94 | ||
95 | write_lock(&keyring_name_lock); | |
96 | ||
97 | if (!keyring_name_hash[bucket].next) | |
98 | INIT_LIST_HEAD(&keyring_name_hash[bucket]); | |
99 | ||
100 | list_add_tail(&keyring->type_data.link, | |
101 | &keyring_name_hash[bucket]); | |
102 | ||
103 | write_unlock(&keyring_name_lock); | |
104 | } | |
105 | ||
106 | } /* end keyring_publish_name() */ | |
107 | ||
108 | /*****************************************************************************/ | |
109 | /* | |
110 | * initialise a keyring | |
111 | * - we object if we were given any data | |
112 | */ | |
113 | static int keyring_instantiate(struct key *keyring, | |
114 | const void *data, size_t datalen) | |
115 | { | |
116 | int ret; | |
117 | ||
118 | ret = -EINVAL; | |
119 | if (datalen == 0) { | |
120 | /* make the keyring available by name if it has one */ | |
121 | keyring_publish_name(keyring); | |
122 | ret = 0; | |
123 | } | |
124 | ||
125 | return ret; | |
126 | ||
127 | } /* end keyring_instantiate() */ | |
128 | ||
1da177e4 LT |
129 | /*****************************************************************************/ |
130 | /* | |
131 | * match keyrings on their name | |
132 | */ | |
133 | static int keyring_match(const struct key *keyring, const void *description) | |
134 | { | |
135 | return keyring->description && | |
136 | strcmp(keyring->description, description) == 0; | |
137 | ||
138 | } /* end keyring_match() */ | |
139 | ||
140 | /*****************************************************************************/ | |
141 | /* | |
142 | * dispose of the data dangling from the corpse of a keyring | |
143 | */ | |
144 | static void keyring_destroy(struct key *keyring) | |
145 | { | |
146 | struct keyring_list *klist; | |
147 | int loop; | |
148 | ||
149 | if (keyring->description) { | |
150 | write_lock(&keyring_name_lock); | |
94efe72f DH |
151 | |
152 | if (keyring->type_data.link.next != NULL && | |
153 | !list_empty(&keyring->type_data.link)) | |
154 | list_del(&keyring->type_data.link); | |
155 | ||
1da177e4 LT |
156 | write_unlock(&keyring_name_lock); |
157 | } | |
158 | ||
e7b0a61b PM |
159 | klist = rcu_dereference_check(keyring->payload.subscriptions, |
160 | rcu_read_lock_held() || | |
161 | atomic_read(&keyring->usage) == 0); | |
1da177e4 LT |
162 | if (klist) { |
163 | for (loop = klist->nkeys - 1; loop >= 0; loop--) | |
164 | key_put(klist->keys[loop]); | |
165 | kfree(klist); | |
166 | } | |
167 | ||
168 | } /* end keyring_destroy() */ | |
169 | ||
170 | /*****************************************************************************/ | |
171 | /* | |
172 | * describe the keyring | |
173 | */ | |
174 | static void keyring_describe(const struct key *keyring, struct seq_file *m) | |
175 | { | |
176 | struct keyring_list *klist; | |
177 | ||
c8563473 | 178 | if (keyring->description) |
1da177e4 | 179 | seq_puts(m, keyring->description); |
c8563473 | 180 | else |
1da177e4 | 181 | seq_puts(m, "[anon]"); |
1da177e4 | 182 | |
76d8aeab DH |
183 | rcu_read_lock(); |
184 | klist = rcu_dereference(keyring->payload.subscriptions); | |
1da177e4 LT |
185 | if (klist) |
186 | seq_printf(m, ": %u/%u", klist->nkeys, klist->maxkeys); | |
187 | else | |
188 | seq_puts(m, ": empty"); | |
76d8aeab | 189 | rcu_read_unlock(); |
1da177e4 LT |
190 | |
191 | } /* end keyring_describe() */ | |
192 | ||
193 | /*****************************************************************************/ | |
194 | /* | |
195 | * read a list of key IDs from the keyring's contents | |
76d8aeab | 196 | * - the keyring's semaphore is read-locked |
1da177e4 LT |
197 | */ |
198 | static long keyring_read(const struct key *keyring, | |
199 | char __user *buffer, size_t buflen) | |
200 | { | |
201 | struct keyring_list *klist; | |
202 | struct key *key; | |
203 | size_t qty, tmp; | |
204 | int loop, ret; | |
205 | ||
206 | ret = 0; | |
f0641cba | 207 | klist = rcu_dereference_locked_keyring(keyring); |
1da177e4 LT |
208 | if (klist) { |
209 | /* calculate how much data we could return */ | |
210 | qty = klist->nkeys * sizeof(key_serial_t); | |
211 | ||
212 | if (buffer && buflen > 0) { | |
213 | if (buflen > qty) | |
214 | buflen = qty; | |
215 | ||
216 | /* copy the IDs of the subscribed keys into the | |
217 | * buffer */ | |
218 | ret = -EFAULT; | |
219 | ||
220 | for (loop = 0; loop < klist->nkeys; loop++) { | |
221 | key = klist->keys[loop]; | |
222 | ||
223 | tmp = sizeof(key_serial_t); | |
224 | if (tmp > buflen) | |
225 | tmp = buflen; | |
226 | ||
227 | if (copy_to_user(buffer, | |
228 | &key->serial, | |
229 | tmp) != 0) | |
230 | goto error; | |
231 | ||
232 | buflen -= tmp; | |
233 | if (buflen == 0) | |
234 | break; | |
235 | buffer += tmp; | |
236 | } | |
237 | } | |
238 | ||
239 | ret = qty; | |
240 | } | |
241 | ||
c5b60b5e | 242 | error: |
1da177e4 LT |
243 | return ret; |
244 | ||
245 | } /* end keyring_read() */ | |
246 | ||
247 | /*****************************************************************************/ | |
248 | /* | |
249 | * allocate a keyring and link into the destination keyring | |
250 | */ | |
251 | struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid, | |
d84f4f99 | 252 | const struct cred *cred, unsigned long flags, |
d720024e | 253 | struct key *dest) |
1da177e4 LT |
254 | { |
255 | struct key *keyring; | |
256 | int ret; | |
257 | ||
258 | keyring = key_alloc(&key_type_keyring, description, | |
d84f4f99 | 259 | uid, gid, cred, |
29db9190 | 260 | (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL, |
7e047ef5 | 261 | flags); |
1da177e4 LT |
262 | |
263 | if (!IS_ERR(keyring)) { | |
3e30148c | 264 | ret = key_instantiate_and_link(keyring, NULL, 0, dest, NULL); |
1da177e4 LT |
265 | if (ret < 0) { |
266 | key_put(keyring); | |
267 | keyring = ERR_PTR(ret); | |
268 | } | |
269 | } | |
270 | ||
271 | return keyring; | |
272 | ||
273 | } /* end keyring_alloc() */ | |
274 | ||
275 | /*****************************************************************************/ | |
276 | /* | |
277 | * search the supplied keyring tree for a key that matches the criterion | |
278 | * - perform a breadth-then-depth search up to the prescribed limit | |
279 | * - we only find keys on which we have search permission | |
280 | * - we use the supplied match function to see if the description (or other | |
281 | * feature of interest) matches | |
3e30148c | 282 | * - we rely on RCU to prevent the keyring lists from disappearing on us |
1da177e4 LT |
283 | * - we return -EAGAIN if we didn't find any matching key |
284 | * - we return -ENOKEY if we only found negative matching keys | |
664cceb0 | 285 | * - we propagate the possession attribute from the keyring ref to the key ref |
1da177e4 | 286 | */ |
664cceb0 | 287 | key_ref_t keyring_search_aux(key_ref_t keyring_ref, |
d84f4f99 | 288 | const struct cred *cred, |
664cceb0 DH |
289 | struct key_type *type, |
290 | const void *description, | |
291 | key_match_func_t match) | |
1da177e4 LT |
292 | { |
293 | struct { | |
76d8aeab | 294 | struct keyring_list *keylist; |
1da177e4 LT |
295 | int kix; |
296 | } stack[KEYRING_SEARCH_MAX_DEPTH]; | |
297 | ||
298 | struct keyring_list *keylist; | |
299 | struct timespec now; | |
dceba994 | 300 | unsigned long possessed, kflags; |
664cceb0 DH |
301 | struct key *keyring, *key; |
302 | key_ref_t key_ref; | |
1da177e4 | 303 | long err; |
76d8aeab | 304 | int sp, kix; |
1da177e4 | 305 | |
664cceb0 DH |
306 | keyring = key_ref_to_ptr(keyring_ref); |
307 | possessed = is_key_possessed(keyring_ref); | |
1da177e4 LT |
308 | key_check(keyring); |
309 | ||
310 | /* top keyring must have search permission to begin the search */ | |
512ea3bc | 311 | err = key_task_permission(keyring_ref, cred, KEY_SEARCH); |
29db9190 DH |
312 | if (err < 0) { |
313 | key_ref = ERR_PTR(err); | |
1da177e4 | 314 | goto error; |
29db9190 | 315 | } |
1da177e4 | 316 | |
664cceb0 | 317 | key_ref = ERR_PTR(-ENOTDIR); |
1da177e4 LT |
318 | if (keyring->type != &key_type_keyring) |
319 | goto error; | |
320 | ||
664cceb0 DH |
321 | rcu_read_lock(); |
322 | ||
1da177e4 LT |
323 | now = current_kernel_time(); |
324 | err = -EAGAIN; | |
325 | sp = 0; | |
326 | ||
dceba994 KC |
327 | /* firstly we should check to see if this top-level keyring is what we |
328 | * are looking for */ | |
329 | key_ref = ERR_PTR(-EAGAIN); | |
330 | kflags = keyring->flags; | |
331 | if (keyring->type == type && match(keyring, description)) { | |
332 | key = keyring; | |
333 | ||
334 | /* check it isn't negative and hasn't expired or been | |
335 | * revoked */ | |
336 | if (kflags & (1 << KEY_FLAG_REVOKED)) | |
337 | goto error_2; | |
338 | if (key->expiry && now.tv_sec >= key->expiry) | |
339 | goto error_2; | |
340 | key_ref = ERR_PTR(-ENOKEY); | |
341 | if (kflags & (1 << KEY_FLAG_NEGATIVE)) | |
342 | goto error_2; | |
343 | goto found; | |
344 | } | |
345 | ||
346 | /* otherwise, the top keyring must not be revoked, expired, or | |
347 | * negatively instantiated if we are to search it */ | |
348 | key_ref = ERR_PTR(-EAGAIN); | |
349 | if (kflags & ((1 << KEY_FLAG_REVOKED) | (1 << KEY_FLAG_NEGATIVE)) || | |
350 | (keyring->expiry && now.tv_sec >= keyring->expiry)) | |
351 | goto error_2; | |
352 | ||
1da177e4 | 353 | /* start processing a new keyring */ |
664cceb0 | 354 | descend: |
76d8aeab | 355 | if (test_bit(KEY_FLAG_REVOKED, &keyring->flags)) |
1da177e4 LT |
356 | goto not_this_keyring; |
357 | ||
76d8aeab | 358 | keylist = rcu_dereference(keyring->payload.subscriptions); |
1da177e4 LT |
359 | if (!keylist) |
360 | goto not_this_keyring; | |
361 | ||
362 | /* iterate through the keys in this keyring first */ | |
363 | for (kix = 0; kix < keylist->nkeys; kix++) { | |
364 | key = keylist->keys[kix]; | |
dceba994 | 365 | kflags = key->flags; |
1da177e4 LT |
366 | |
367 | /* ignore keys not of this type */ | |
368 | if (key->type != type) | |
369 | continue; | |
370 | ||
371 | /* skip revoked keys and expired keys */ | |
dceba994 | 372 | if (kflags & (1 << KEY_FLAG_REVOKED)) |
1da177e4 LT |
373 | continue; |
374 | ||
375 | if (key->expiry && now.tv_sec >= key->expiry) | |
376 | continue; | |
377 | ||
378 | /* keys that don't match */ | |
379 | if (!match(key, description)) | |
380 | continue; | |
381 | ||
382 | /* key must have search permissions */ | |
29db9190 | 383 | if (key_task_permission(make_key_ref(key, possessed), |
d84f4f99 | 384 | cred, KEY_SEARCH) < 0) |
1da177e4 LT |
385 | continue; |
386 | ||
dceba994 KC |
387 | /* we set a different error code if we pass a negative key */ |
388 | if (kflags & (1 << KEY_FLAG_NEGATIVE)) { | |
1da177e4 LT |
389 | err = -ENOKEY; |
390 | continue; | |
391 | } | |
392 | ||
393 | goto found; | |
394 | } | |
395 | ||
396 | /* search through the keyrings nested in this one */ | |
397 | kix = 0; | |
664cceb0 | 398 | ascend: |
76d8aeab | 399 | for (; kix < keylist->nkeys; kix++) { |
1da177e4 LT |
400 | key = keylist->keys[kix]; |
401 | if (key->type != &key_type_keyring) | |
76d8aeab | 402 | continue; |
1da177e4 LT |
403 | |
404 | /* recursively search nested keyrings | |
405 | * - only search keyrings for which we have search permission | |
406 | */ | |
407 | if (sp >= KEYRING_SEARCH_MAX_DEPTH) | |
76d8aeab | 408 | continue; |
1da177e4 | 409 | |
0f6ed7c2 | 410 | if (key_task_permission(make_key_ref(key, possessed), |
d84f4f99 | 411 | cred, KEY_SEARCH) < 0) |
76d8aeab | 412 | continue; |
1da177e4 LT |
413 | |
414 | /* stack the current position */ | |
76d8aeab | 415 | stack[sp].keylist = keylist; |
1da177e4 LT |
416 | stack[sp].kix = kix; |
417 | sp++; | |
418 | ||
419 | /* begin again with the new keyring */ | |
420 | keyring = key; | |
421 | goto descend; | |
1da177e4 LT |
422 | } |
423 | ||
424 | /* the keyring we're looking at was disqualified or didn't contain a | |
425 | * matching key */ | |
664cceb0 | 426 | not_this_keyring: |
1da177e4 LT |
427 | if (sp > 0) { |
428 | /* resume the processing of a keyring higher up in the tree */ | |
429 | sp--; | |
76d8aeab | 430 | keylist = stack[sp].keylist; |
1da177e4 LT |
431 | kix = stack[sp].kix + 1; |
432 | goto ascend; | |
433 | } | |
434 | ||
664cceb0 DH |
435 | key_ref = ERR_PTR(err); |
436 | goto error_2; | |
1da177e4 LT |
437 | |
438 | /* we found a viable match */ | |
664cceb0 | 439 | found: |
1da177e4 | 440 | atomic_inc(&key->usage); |
1da177e4 | 441 | key_check(key); |
664cceb0 DH |
442 | key_ref = make_key_ref(key, possessed); |
443 | error_2: | |
76d8aeab | 444 | rcu_read_unlock(); |
664cceb0 DH |
445 | error: |
446 | return key_ref; | |
1da177e4 LT |
447 | |
448 | } /* end keyring_search_aux() */ | |
449 | ||
450 | /*****************************************************************************/ | |
451 | /* | |
452 | * search the supplied keyring tree for a key that matches the criterion | |
453 | * - perform a breadth-then-depth search up to the prescribed limit | |
454 | * - we only find keys on which we have search permission | |
455 | * - we readlock the keyrings as we search down the tree | |
456 | * - we return -EAGAIN if we didn't find any matching key | |
457 | * - we return -ENOKEY if we only found negative matching keys | |
458 | */ | |
664cceb0 DH |
459 | key_ref_t keyring_search(key_ref_t keyring, |
460 | struct key_type *type, | |
461 | const char *description) | |
1da177e4 | 462 | { |
3e30148c DH |
463 | if (!type->match) |
464 | return ERR_PTR(-ENOKEY); | |
465 | ||
d84f4f99 | 466 | return keyring_search_aux(keyring, current->cred, |
3e30148c | 467 | type, description, type->match); |
1da177e4 LT |
468 | |
469 | } /* end keyring_search() */ | |
470 | ||
471 | EXPORT_SYMBOL(keyring_search); | |
472 | ||
473 | /*****************************************************************************/ | |
474 | /* | |
475 | * search the given keyring only (no recursion) | |
476 | * - keyring must be locked by caller | |
c3a9d654 | 477 | * - caller must guarantee that the keyring is a keyring |
1da177e4 | 478 | */ |
664cceb0 DH |
479 | key_ref_t __keyring_search_one(key_ref_t keyring_ref, |
480 | const struct key_type *ktype, | |
481 | const char *description, | |
482 | key_perm_t perm) | |
1da177e4 LT |
483 | { |
484 | struct keyring_list *klist; | |
664cceb0 DH |
485 | unsigned long possessed; |
486 | struct key *keyring, *key; | |
1da177e4 LT |
487 | int loop; |
488 | ||
664cceb0 DH |
489 | keyring = key_ref_to_ptr(keyring_ref); |
490 | possessed = is_key_possessed(keyring_ref); | |
491 | ||
76d8aeab DH |
492 | rcu_read_lock(); |
493 | ||
494 | klist = rcu_dereference(keyring->payload.subscriptions); | |
1da177e4 LT |
495 | if (klist) { |
496 | for (loop = 0; loop < klist->nkeys; loop++) { | |
497 | key = klist->keys[loop]; | |
498 | ||
499 | if (key->type == ktype && | |
3e30148c DH |
500 | (!key->type->match || |
501 | key->type->match(key, description)) && | |
664cceb0 | 502 | key_permission(make_key_ref(key, possessed), |
db1d1d57 | 503 | perm) == 0 && |
76d8aeab | 504 | !test_bit(KEY_FLAG_REVOKED, &key->flags) |
1da177e4 LT |
505 | ) |
506 | goto found; | |
507 | } | |
508 | } | |
509 | ||
664cceb0 DH |
510 | rcu_read_unlock(); |
511 | return ERR_PTR(-ENOKEY); | |
1da177e4 | 512 | |
c5b60b5e | 513 | found: |
1da177e4 | 514 | atomic_inc(&key->usage); |
76d8aeab | 515 | rcu_read_unlock(); |
664cceb0 | 516 | return make_key_ref(key, possessed); |
1da177e4 LT |
517 | |
518 | } /* end __keyring_search_one() */ | |
519 | ||
520 | /*****************************************************************************/ | |
521 | /* | |
522 | * find a keyring with the specified name | |
523 | * - all named keyrings are searched | |
69664cf1 | 524 | * - normally only finds keyrings with search permission for the current process |
1da177e4 | 525 | */ |
69664cf1 | 526 | struct key *find_keyring_by_name(const char *name, bool skip_perm_check) |
1da177e4 LT |
527 | { |
528 | struct key *keyring; | |
529 | int bucket; | |
530 | ||
1da177e4 | 531 | if (!name) |
cea7daa3 | 532 | return ERR_PTR(-EINVAL); |
1da177e4 LT |
533 | |
534 | bucket = keyring_hash(name); | |
535 | ||
536 | read_lock(&keyring_name_lock); | |
537 | ||
538 | if (keyring_name_hash[bucket].next) { | |
539 | /* search this hash bucket for a keyring with a matching name | |
540 | * that's readable and that hasn't been revoked */ | |
541 | list_for_each_entry(keyring, | |
542 | &keyring_name_hash[bucket], | |
543 | type_data.link | |
544 | ) { | |
2ea190d0 SH |
545 | if (keyring->user->user_ns != current_user_ns()) |
546 | continue; | |
547 | ||
76d8aeab | 548 | if (test_bit(KEY_FLAG_REVOKED, &keyring->flags)) |
1da177e4 LT |
549 | continue; |
550 | ||
551 | if (strcmp(keyring->description, name) != 0) | |
552 | continue; | |
553 | ||
69664cf1 DH |
554 | if (!skip_perm_check && |
555 | key_permission(make_key_ref(keyring, 0), | |
0f6ed7c2 | 556 | KEY_SEARCH) < 0) |
1da177e4 LT |
557 | continue; |
558 | ||
cea7daa3 TO |
559 | /* we've got a match but we might end up racing with |
560 | * key_cleanup() if the keyring is currently 'dead' | |
561 | * (ie. it has a zero usage count) */ | |
562 | if (!atomic_inc_not_zero(&keyring->usage)) | |
563 | continue; | |
564 | goto out; | |
1da177e4 LT |
565 | } |
566 | } | |
567 | ||
1da177e4 | 568 | keyring = ERR_PTR(-ENOKEY); |
cea7daa3 TO |
569 | out: |
570 | read_unlock(&keyring_name_lock); | |
1da177e4 LT |
571 | return keyring; |
572 | ||
573 | } /* end find_keyring_by_name() */ | |
574 | ||
575 | /*****************************************************************************/ | |
576 | /* | |
577 | * see if a cycle will will be created by inserting acyclic tree B in acyclic | |
578 | * tree A at the topmost level (ie: as a direct child of A) | |
579 | * - since we are adding B to A at the top level, checking for cycles should | |
580 | * just be a matter of seeing if node A is somewhere in tree B | |
581 | */ | |
582 | static int keyring_detect_cycle(struct key *A, struct key *B) | |
583 | { | |
584 | struct { | |
76d8aeab | 585 | struct keyring_list *keylist; |
1da177e4 LT |
586 | int kix; |
587 | } stack[KEYRING_SEARCH_MAX_DEPTH]; | |
588 | ||
589 | struct keyring_list *keylist; | |
590 | struct key *subtree, *key; | |
591 | int sp, kix, ret; | |
592 | ||
76d8aeab DH |
593 | rcu_read_lock(); |
594 | ||
1da177e4 LT |
595 | ret = -EDEADLK; |
596 | if (A == B) | |
76d8aeab | 597 | goto cycle_detected; |
1da177e4 LT |
598 | |
599 | subtree = B; | |
600 | sp = 0; | |
601 | ||
602 | /* start processing a new keyring */ | |
c5b60b5e | 603 | descend: |
76d8aeab | 604 | if (test_bit(KEY_FLAG_REVOKED, &subtree->flags)) |
1da177e4 LT |
605 | goto not_this_keyring; |
606 | ||
76d8aeab | 607 | keylist = rcu_dereference(subtree->payload.subscriptions); |
1da177e4 LT |
608 | if (!keylist) |
609 | goto not_this_keyring; | |
610 | kix = 0; | |
611 | ||
c5b60b5e | 612 | ascend: |
1da177e4 LT |
613 | /* iterate through the remaining keys in this keyring */ |
614 | for (; kix < keylist->nkeys; kix++) { | |
615 | key = keylist->keys[kix]; | |
616 | ||
617 | if (key == A) | |
618 | goto cycle_detected; | |
619 | ||
620 | /* recursively check nested keyrings */ | |
621 | if (key->type == &key_type_keyring) { | |
622 | if (sp >= KEYRING_SEARCH_MAX_DEPTH) | |
623 | goto too_deep; | |
624 | ||
625 | /* stack the current position */ | |
76d8aeab | 626 | stack[sp].keylist = keylist; |
1da177e4 LT |
627 | stack[sp].kix = kix; |
628 | sp++; | |
629 | ||
630 | /* begin again with the new keyring */ | |
631 | subtree = key; | |
632 | goto descend; | |
633 | } | |
634 | } | |
635 | ||
636 | /* the keyring we're looking at was disqualified or didn't contain a | |
637 | * matching key */ | |
c5b60b5e | 638 | not_this_keyring: |
1da177e4 LT |
639 | if (sp > 0) { |
640 | /* resume the checking of a keyring higher up in the tree */ | |
641 | sp--; | |
76d8aeab | 642 | keylist = stack[sp].keylist; |
1da177e4 LT |
643 | kix = stack[sp].kix + 1; |
644 | goto ascend; | |
645 | } | |
646 | ||
647 | ret = 0; /* no cycles detected */ | |
648 | ||
c5b60b5e | 649 | error: |
76d8aeab | 650 | rcu_read_unlock(); |
1da177e4 LT |
651 | return ret; |
652 | ||
c5b60b5e | 653 | too_deep: |
1da177e4 | 654 | ret = -ELOOP; |
76d8aeab DH |
655 | goto error; |
656 | ||
c5b60b5e | 657 | cycle_detected: |
1da177e4 | 658 | ret = -EDEADLK; |
1da177e4 LT |
659 | goto error; |
660 | ||
661 | } /* end keyring_detect_cycle() */ | |
662 | ||
cab8eb59 DH |
663 | /* |
664 | * dispose of a keyring list after the RCU grace period, freeing the unlinked | |
665 | * key | |
666 | */ | |
667 | static void keyring_unlink_rcu_disposal(struct rcu_head *rcu) | |
668 | { | |
669 | struct keyring_list *klist = | |
670 | container_of(rcu, struct keyring_list, rcu); | |
671 | ||
4be929be | 672 | if (klist->delkey != USHRT_MAX) |
f70e2e06 | 673 | key_put(klist->keys[klist->delkey]); |
cab8eb59 | 674 | kfree(klist); |
f70e2e06 | 675 | } |
cab8eb59 | 676 | |
1da177e4 | 677 | /* |
f70e2e06 | 678 | * preallocate memory so that a key can be linked into to a keyring |
1da177e4 | 679 | */ |
f70e2e06 DH |
680 | int __key_link_begin(struct key *keyring, const struct key_type *type, |
681 | const char *description, | |
682 | struct keyring_list **_prealloc) | |
683 | __acquires(&keyring->sem) | |
1da177e4 LT |
684 | { |
685 | struct keyring_list *klist, *nklist; | |
686 | unsigned max; | |
687 | size_t size; | |
cab8eb59 | 688 | int loop, ret; |
1da177e4 | 689 | |
f70e2e06 | 690 | kenter("%d,%s,%s,", key_serial(keyring), type->name, description); |
1da177e4 | 691 | |
1da177e4 | 692 | if (keyring->type != &key_type_keyring) |
f70e2e06 DH |
693 | return -ENOTDIR; |
694 | ||
695 | down_write(&keyring->sem); | |
696 | ||
697 | ret = -EKEYREVOKED; | |
698 | if (test_bit(KEY_FLAG_REVOKED, &keyring->flags)) | |
699 | goto error_krsem; | |
1da177e4 | 700 | |
f70e2e06 DH |
701 | /* serialise link/link calls to prevent parallel calls causing a cycle |
702 | * when linking two keyring in opposite orders */ | |
703 | if (type == &key_type_keyring) | |
553d603c DH |
704 | down_write(&keyring_serialise_link_sem); |
705 | ||
f70e2e06 | 706 | klist = rcu_dereference_locked_keyring(keyring); |
1da177e4 | 707 | |
cab8eb59 | 708 | /* see if there's a matching key we can displace */ |
cab8eb59 | 709 | if (klist && klist->nkeys > 0) { |
cab8eb59 DH |
710 | for (loop = klist->nkeys - 1; loop >= 0; loop--) { |
711 | if (klist->keys[loop]->type == type && | |
712 | strcmp(klist->keys[loop]->description, | |
f70e2e06 | 713 | description) == 0 |
cab8eb59 | 714 | ) { |
f70e2e06 DH |
715 | /* found a match - we'll replace this one with |
716 | * the new key */ | |
cab8eb59 DH |
717 | size = sizeof(struct key *) * klist->maxkeys; |
718 | size += sizeof(*klist); | |
719 | BUG_ON(size > PAGE_SIZE); | |
720 | ||
721 | ret = -ENOMEM; | |
48ad504e | 722 | nklist = kmemdup(klist, size, GFP_KERNEL); |
cab8eb59 | 723 | if (!nklist) |
f70e2e06 | 724 | goto error_sem; |
cab8eb59 | 725 | |
f70e2e06 DH |
726 | /* note replacement slot */ |
727 | klist->delkey = nklist->delkey = loop; | |
cab8eb59 DH |
728 | goto done; |
729 | } | |
730 | } | |
731 | } | |
732 | ||
1da177e4 LT |
733 | /* check that we aren't going to overrun the user's quota */ |
734 | ret = key_payload_reserve(keyring, | |
735 | keyring->datalen + KEYQUOTA_LINK_BYTES); | |
736 | if (ret < 0) | |
f70e2e06 | 737 | goto error_sem; |
1da177e4 | 738 | |
1da177e4 | 739 | if (klist && klist->nkeys < klist->maxkeys) { |
f70e2e06 DH |
740 | /* there's sufficient slack space to append directly */ |
741 | nklist = NULL; | |
512ea3bc | 742 | } else { |
1da177e4 LT |
743 | /* grow the key list */ |
744 | max = 4; | |
745 | if (klist) | |
746 | max += klist->maxkeys; | |
747 | ||
748 | ret = -ENFILE; | |
4be929be | 749 | if (max > USHRT_MAX - 1) |
f70e2e06 | 750 | goto error_quota; |
a4014d8f | 751 | size = sizeof(*klist) + sizeof(struct key *) * max; |
1da177e4 | 752 | if (size > PAGE_SIZE) |
f70e2e06 | 753 | goto error_quota; |
1da177e4 LT |
754 | |
755 | ret = -ENOMEM; | |
756 | nklist = kmalloc(size, GFP_KERNEL); | |
757 | if (!nklist) | |
f70e2e06 | 758 | goto error_quota; |
1da177e4 | 759 | |
f70e2e06 | 760 | nklist->maxkeys = max; |
1da177e4 | 761 | if (klist) { |
f70e2e06 | 762 | memcpy(nklist->keys, klist->keys, |
1da177e4 | 763 | sizeof(struct key *) * klist->nkeys); |
f70e2e06 DH |
764 | nklist->delkey = klist->nkeys; |
765 | nklist->nkeys = klist->nkeys + 1; | |
4be929be | 766 | klist->delkey = USHRT_MAX; |
f70e2e06 DH |
767 | } else { |
768 | nklist->nkeys = 1; | |
769 | nklist->delkey = 0; | |
1da177e4 LT |
770 | } |
771 | ||
772 | /* add the key into the new space */ | |
f70e2e06 | 773 | nklist->keys[nklist->delkey] = NULL; |
1da177e4 LT |
774 | } |
775 | ||
cab8eb59 | 776 | done: |
f70e2e06 DH |
777 | *_prealloc = nklist; |
778 | kleave(" = 0"); | |
779 | return 0; | |
1da177e4 | 780 | |
f70e2e06 | 781 | error_quota: |
1da177e4 LT |
782 | /* undo the quota changes */ |
783 | key_payload_reserve(keyring, | |
784 | keyring->datalen - KEYQUOTA_LINK_BYTES); | |
f70e2e06 DH |
785 | error_sem: |
786 | if (type == &key_type_keyring) | |
787 | up_write(&keyring_serialise_link_sem); | |
788 | error_krsem: | |
789 | up_write(&keyring->sem); | |
790 | kleave(" = %d", ret); | |
791 | return ret; | |
792 | } | |
1da177e4 | 793 | |
f70e2e06 DH |
794 | /* |
795 | * check already instantiated keys aren't going to be a problem | |
796 | * - the caller must have called __key_link_begin() | |
797 | * - don't need to call this for keys that were created since __key_link_begin() | |
798 | * was called | |
799 | */ | |
800 | int __key_link_check_live_key(struct key *keyring, struct key *key) | |
801 | { | |
802 | if (key->type == &key_type_keyring) | |
803 | /* check that we aren't going to create a cycle by linking one | |
804 | * keyring to another */ | |
805 | return keyring_detect_cycle(keyring, key); | |
806 | return 0; | |
807 | } | |
808 | ||
809 | /* | |
810 | * link a key into to a keyring | |
811 | * - must be called with __key_link_begin() having being called | |
812 | * - discard already extant link to matching key if there is one | |
813 | */ | |
814 | void __key_link(struct key *keyring, struct key *key, | |
815 | struct keyring_list **_prealloc) | |
816 | { | |
817 | struct keyring_list *klist, *nklist; | |
818 | ||
819 | nklist = *_prealloc; | |
820 | *_prealloc = NULL; | |
821 | ||
822 | kenter("%d,%d,%p", keyring->serial, key->serial, nklist); | |
823 | ||
824 | klist = rcu_dereference_protected(keyring->payload.subscriptions, | |
825 | rwsem_is_locked(&keyring->sem)); | |
826 | ||
827 | atomic_inc(&key->usage); | |
828 | ||
829 | /* there's a matching key we can displace or an empty slot in a newly | |
830 | * allocated list we can fill */ | |
831 | if (nklist) { | |
832 | kdebug("replace %hu/%hu/%hu", | |
833 | nklist->delkey, nklist->nkeys, nklist->maxkeys); | |
834 | ||
835 | nklist->keys[nklist->delkey] = key; | |
836 | ||
837 | rcu_assign_pointer(keyring->payload.subscriptions, nklist); | |
838 | ||
839 | /* dispose of the old keyring list and, if there was one, the | |
840 | * displaced key */ | |
841 | if (klist) { | |
842 | kdebug("dispose %hu/%hu/%hu", | |
843 | klist->delkey, klist->nkeys, klist->maxkeys); | |
844 | call_rcu(&klist->rcu, keyring_unlink_rcu_disposal); | |
845 | } | |
846 | } else { | |
847 | /* there's sufficient slack space to append directly */ | |
848 | klist->keys[klist->nkeys] = key; | |
849 | smp_wmb(); | |
850 | klist->nkeys++; | |
851 | } | |
852 | } | |
853 | ||
854 | /* | |
855 | * finish linking a key into to a keyring | |
856 | * - must be called with __key_link_begin() having being called | |
857 | */ | |
858 | void __key_link_end(struct key *keyring, struct key_type *type, | |
859 | struct keyring_list *prealloc) | |
860 | __releases(&keyring->sem) | |
861 | { | |
862 | BUG_ON(type == NULL); | |
863 | BUG_ON(type->name == NULL); | |
864 | kenter("%d,%s,%p", keyring->serial, type->name, prealloc); | |
865 | ||
866 | if (type == &key_type_keyring) | |
867 | up_write(&keyring_serialise_link_sem); | |
868 | ||
869 | if (prealloc) { | |
870 | kfree(prealloc); | |
871 | key_payload_reserve(keyring, | |
872 | keyring->datalen - KEYQUOTA_LINK_BYTES); | |
873 | } | |
874 | up_write(&keyring->sem); | |
875 | } | |
1da177e4 | 876 | |
1da177e4 LT |
877 | /* |
878 | * link a key to a keyring | |
879 | */ | |
880 | int key_link(struct key *keyring, struct key *key) | |
881 | { | |
f70e2e06 | 882 | struct keyring_list *prealloc; |
1da177e4 LT |
883 | int ret; |
884 | ||
885 | key_check(keyring); | |
886 | key_check(key); | |
887 | ||
f70e2e06 DH |
888 | ret = __key_link_begin(keyring, key->type, key->description, &prealloc); |
889 | if (ret == 0) { | |
890 | ret = __key_link_check_live_key(keyring, key); | |
891 | if (ret == 0) | |
892 | __key_link(keyring, key, &prealloc); | |
893 | __key_link_end(keyring, key->type, prealloc); | |
894 | } | |
1da177e4 LT |
895 | |
896 | return ret; | |
f70e2e06 | 897 | } |
1da177e4 LT |
898 | |
899 | EXPORT_SYMBOL(key_link); | |
900 | ||
901 | /*****************************************************************************/ | |
902 | /* | |
903 | * unlink the first link to a key from a keyring | |
904 | */ | |
905 | int key_unlink(struct key *keyring, struct key *key) | |
906 | { | |
76d8aeab | 907 | struct keyring_list *klist, *nklist; |
1da177e4 LT |
908 | int loop, ret; |
909 | ||
910 | key_check(keyring); | |
911 | key_check(key); | |
912 | ||
913 | ret = -ENOTDIR; | |
914 | if (keyring->type != &key_type_keyring) | |
915 | goto error; | |
916 | ||
917 | down_write(&keyring->sem); | |
918 | ||
f0641cba | 919 | klist = rcu_dereference_locked_keyring(keyring); |
1da177e4 LT |
920 | if (klist) { |
921 | /* search the keyring for the key */ | |
922 | for (loop = 0; loop < klist->nkeys; loop++) | |
923 | if (klist->keys[loop] == key) | |
924 | goto key_is_present; | |
925 | } | |
926 | ||
927 | up_write(&keyring->sem); | |
928 | ret = -ENOENT; | |
929 | goto error; | |
930 | ||
76d8aeab DH |
931 | key_is_present: |
932 | /* we need to copy the key list for RCU purposes */ | |
a4014d8f DH |
933 | nklist = kmalloc(sizeof(*klist) + |
934 | sizeof(struct key *) * klist->maxkeys, | |
76d8aeab DH |
935 | GFP_KERNEL); |
936 | if (!nklist) | |
937 | goto nomem; | |
938 | nklist->maxkeys = klist->maxkeys; | |
939 | nklist->nkeys = klist->nkeys - 1; | |
940 | ||
941 | if (loop > 0) | |
942 | memcpy(&nklist->keys[0], | |
943 | &klist->keys[0], | |
a4014d8f | 944 | loop * sizeof(struct key *)); |
76d8aeab DH |
945 | |
946 | if (loop < nklist->nkeys) | |
947 | memcpy(&nklist->keys[loop], | |
948 | &klist->keys[loop + 1], | |
a4014d8f | 949 | (nklist->nkeys - loop) * sizeof(struct key *)); |
76d8aeab | 950 | |
1da177e4 LT |
951 | /* adjust the user's quota */ |
952 | key_payload_reserve(keyring, | |
953 | keyring->datalen - KEYQUOTA_LINK_BYTES); | |
954 | ||
76d8aeab | 955 | rcu_assign_pointer(keyring->payload.subscriptions, nklist); |
1da177e4 | 956 | |
76d8aeab | 957 | up_write(&keyring->sem); |
1da177e4 | 958 | |
76d8aeab DH |
959 | /* schedule for later cleanup */ |
960 | klist->delkey = loop; | |
961 | call_rcu(&klist->rcu, keyring_unlink_rcu_disposal); | |
1da177e4 | 962 | |
1da177e4 LT |
963 | ret = 0; |
964 | ||
76d8aeab | 965 | error: |
1da177e4 | 966 | return ret; |
76d8aeab DH |
967 | nomem: |
968 | ret = -ENOMEM; | |
969 | up_write(&keyring->sem); | |
970 | goto error; | |
1da177e4 LT |
971 | |
972 | } /* end key_unlink() */ | |
973 | ||
974 | EXPORT_SYMBOL(key_unlink); | |
975 | ||
76d8aeab DH |
976 | /*****************************************************************************/ |
977 | /* | |
978 | * dispose of a keyring list after the RCU grace period, releasing the keys it | |
979 | * links to | |
980 | */ | |
981 | static void keyring_clear_rcu_disposal(struct rcu_head *rcu) | |
982 | { | |
983 | struct keyring_list *klist; | |
984 | int loop; | |
985 | ||
986 | klist = container_of(rcu, struct keyring_list, rcu); | |
987 | ||
988 | for (loop = klist->nkeys - 1; loop >= 0; loop--) | |
989 | key_put(klist->keys[loop]); | |
990 | ||
991 | kfree(klist); | |
992 | ||
993 | } /* end keyring_clear_rcu_disposal() */ | |
994 | ||
1da177e4 LT |
995 | /*****************************************************************************/ |
996 | /* | |
997 | * clear the specified process keyring | |
998 | * - implements keyctl(KEYCTL_CLEAR) | |
999 | */ | |
1000 | int keyring_clear(struct key *keyring) | |
1001 | { | |
1002 | struct keyring_list *klist; | |
76d8aeab | 1003 | int ret; |
1da177e4 LT |
1004 | |
1005 | ret = -ENOTDIR; | |
1006 | if (keyring->type == &key_type_keyring) { | |
1007 | /* detach the pointer block with the locks held */ | |
1008 | down_write(&keyring->sem); | |
1009 | ||
f0641cba | 1010 | klist = rcu_dereference_locked_keyring(keyring); |
1da177e4 LT |
1011 | if (klist) { |
1012 | /* adjust the quota */ | |
1013 | key_payload_reserve(keyring, | |
1014 | sizeof(struct keyring_list)); | |
1015 | ||
76d8aeab DH |
1016 | rcu_assign_pointer(keyring->payload.subscriptions, |
1017 | NULL); | |
1da177e4 LT |
1018 | } |
1019 | ||
1020 | up_write(&keyring->sem); | |
1021 | ||
1022 | /* free the keys after the locks have been dropped */ | |
76d8aeab DH |
1023 | if (klist) |
1024 | call_rcu(&klist->rcu, keyring_clear_rcu_disposal); | |
1da177e4 LT |
1025 | |
1026 | ret = 0; | |
1027 | } | |
1028 | ||
1029 | return ret; | |
1030 | ||
1031 | } /* end keyring_clear() */ | |
1032 | ||
1033 | EXPORT_SYMBOL(keyring_clear); | |
31204ed9 DH |
1034 | |
1035 | /*****************************************************************************/ | |
1036 | /* | |
1037 | * dispose of the links from a revoked keyring | |
1038 | * - called with the key sem write-locked | |
1039 | */ | |
1040 | static void keyring_revoke(struct key *keyring) | |
1041 | { | |
f0641cba DH |
1042 | struct keyring_list *klist; |
1043 | ||
1044 | klist = rcu_dereference_locked_keyring(keyring); | |
31204ed9 DH |
1045 | |
1046 | /* adjust the quota */ | |
1047 | key_payload_reserve(keyring, 0); | |
1048 | ||
1049 | if (klist) { | |
1050 | rcu_assign_pointer(keyring->payload.subscriptions, NULL); | |
1051 | call_rcu(&klist->rcu, keyring_clear_rcu_disposal); | |
1052 | } | |
1053 | ||
1054 | } /* end keyring_revoke() */ | |
5d135440 DH |
1055 | |
1056 | /* | |
1057 | * Determine whether a key is dead | |
1058 | */ | |
1059 | static bool key_is_dead(struct key *key, time_t limit) | |
1060 | { | |
1061 | return test_bit(KEY_FLAG_DEAD, &key->flags) || | |
1062 | (key->expiry > 0 && key->expiry <= limit); | |
1063 | } | |
1064 | ||
1065 | /* | |
1066 | * Collect garbage from the contents of a keyring | |
1067 | */ | |
1068 | void keyring_gc(struct key *keyring, time_t limit) | |
1069 | { | |
1070 | struct keyring_list *klist, *new; | |
1071 | struct key *key; | |
1072 | int loop, keep, max; | |
1073 | ||
c08ef808 | 1074 | kenter("{%x,%s}", key_serial(keyring), keyring->description); |
5d135440 DH |
1075 | |
1076 | down_write(&keyring->sem); | |
1077 | ||
f0641cba | 1078 | klist = rcu_dereference_locked_keyring(keyring); |
5d135440 | 1079 | if (!klist) |
c08ef808 | 1080 | goto no_klist; |
5d135440 DH |
1081 | |
1082 | /* work out how many subscriptions we're keeping */ | |
1083 | keep = 0; | |
1084 | for (loop = klist->nkeys - 1; loop >= 0; loop--) | |
c08ef808 | 1085 | if (!key_is_dead(klist->keys[loop], limit)) |
5d135440 DH |
1086 | keep++; |
1087 | ||
1088 | if (keep == klist->nkeys) | |
1089 | goto just_return; | |
1090 | ||
1091 | /* allocate a new keyring payload */ | |
1092 | max = roundup(keep, 4); | |
1093 | new = kmalloc(sizeof(struct keyring_list) + max * sizeof(struct key *), | |
1094 | GFP_KERNEL); | |
1095 | if (!new) | |
c08ef808 | 1096 | goto nomem; |
5d135440 DH |
1097 | new->maxkeys = max; |
1098 | new->nkeys = 0; | |
1099 | new->delkey = 0; | |
1100 | ||
1101 | /* install the live keys | |
1102 | * - must take care as expired keys may be updated back to life | |
1103 | */ | |
1104 | keep = 0; | |
1105 | for (loop = klist->nkeys - 1; loop >= 0; loop--) { | |
1106 | key = klist->keys[loop]; | |
1107 | if (!key_is_dead(key, limit)) { | |
1108 | if (keep >= max) | |
1109 | goto discard_new; | |
1110 | new->keys[keep++] = key_get(key); | |
1111 | } | |
1112 | } | |
1113 | new->nkeys = keep; | |
1114 | ||
1115 | /* adjust the quota */ | |
1116 | key_payload_reserve(keyring, | |
1117 | sizeof(struct keyring_list) + | |
1118 | KEYQUOTA_LINK_BYTES * keep); | |
1119 | ||
1120 | if (keep == 0) { | |
1121 | rcu_assign_pointer(keyring->payload.subscriptions, NULL); | |
1122 | kfree(new); | |
1123 | } else { | |
1124 | rcu_assign_pointer(keyring->payload.subscriptions, new); | |
1125 | } | |
1126 | ||
1127 | up_write(&keyring->sem); | |
1128 | ||
1129 | call_rcu(&klist->rcu, keyring_clear_rcu_disposal); | |
1130 | kleave(" [yes]"); | |
1131 | return; | |
1132 | ||
1133 | discard_new: | |
1134 | new->nkeys = keep; | |
1135 | keyring_clear_rcu_disposal(&new->rcu); | |
c08ef808 DH |
1136 | up_write(&keyring->sem); |
1137 | kleave(" [discard]"); | |
1138 | return; | |
1139 | ||
5d135440 DH |
1140 | just_return: |
1141 | up_write(&keyring->sem); | |
c08ef808 DH |
1142 | kleave(" [no dead]"); |
1143 | return; | |
1144 | ||
1145 | no_klist: | |
1146 | up_write(&keyring->sem); | |
1147 | kleave(" [no_klist]"); | |
1148 | return; | |
1149 | ||
1150 | nomem: | |
1151 | up_write(&keyring->sem); | |
1152 | kleave(" [oom]"); | |
5d135440 | 1153 | } |