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1/*
2 * AppArmor security module
3 *
4 * This file contains AppArmor policy manipulation functions
5 *
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2010 Canonical Ltd.
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation, version 2 of the
12 * License.
13 *
14 *
15 * AppArmor policy is based around profiles, which contain the rules a
16 * task is confined by. Every task in the system has a profile attached
17 * to it determined either by matching "unconfined" tasks against the
18 * visible set of profiles or by following a profiles attachment rules.
19 *
20 * Each profile exists in a profile namespace which is a container of
21 * visible profiles. Each namespace contains a special "unconfined" profile,
22 * which doesn't enforce any confinement on a task beyond DAC.
23 *
24 * Namespace and profile names can be written together in either
25 * of two syntaxes.
26 * :namespace:profile - used by kernel interfaces for easy detection
27 * namespace://profile - used by policy
28 *
29 * Profile names can not start with : or @ or ^ and may not contain \0
30 *
31 * Reserved profile names
32 * unconfined - special automatically generated unconfined profile
33 * inherit - special name to indicate profile inheritance
34 * null-XXXX-YYYY - special automatically generated learning profiles
35 *
36 * Namespace names may not start with / or @ and may not contain \0 or :
37 * Reserved namespace names
38 * user-XXXX - user defined profiles
39 *
40 * a // in a profile or namespace name indicates a hierarchical name with the
41 * name before the // being the parent and the name after the child.
42 *
43 * Profile and namespace hierarchies serve two different but similar purposes.
44 * The namespace contains the set of visible profiles that are considered
45 * for attachment. The hierarchy of namespaces allows for virtualizing
46 * the namespace so that for example a chroot can have its own set of profiles
47 * which may define some local user namespaces.
48 * The profile hierarchy severs two distinct purposes,
49 * - it allows for sub profiles or hats, which allows an application to run
50 * subprograms under its own profile with different restriction than it
51 * self, and not have it use the system profile.
52 * eg. if a mail program starts an editor, the policy might make the
53 * restrictions tighter on the editor tighter than the mail program,
54 * and definitely different than general editor restrictions
55 * - it allows for binary hierarchy of profiles, so that execution history
56 * is preserved. This feature isn't exploited by AppArmor reference policy
57 * but is allowed. NOTE: this is currently suboptimal because profile
58 * aliasing is not currently implemented so that a profile for each
59 * level must be defined.
60 * eg. /bin/bash///bin/ls as a name would indicate /bin/ls was started
61 * from /bin/bash
62 *
63 * A profile or namespace name that can contain one or more // separators
64 * is referred to as an hname (hierarchical).
65 * eg. /bin/bash//bin/ls
66 *
67 * An fqname is a name that may contain both namespace and profile hnames.
68 * eg. :ns:/bin/bash//bin/ls
69 *
70 * NOTES:
71 * - locking of profile lists is currently fairly coarse. All profile
72 * lists within a namespace use the namespace lock.
73 * FIXME: move profile lists to using rcu_lists
74 */
75
76#include <linux/slab.h>
77#include <linux/spinlock.h>
78#include <linux/string.h>
80594fc2 79#include <linux/user_namespace.h>
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80
81#include "include/apparmor.h"
82#include "include/capability.h"
83#include "include/context.h"
84#include "include/file.h"
85#include "include/ipc.h"
80594fc2 86#include "include/label.h"
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87#include "include/match.h"
88#include "include/path.h"
89#include "include/policy.h"
0acae0c2 90#include "include/policy_ns.h"
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91#include "include/policy_unpack.h"
92#include "include/resource.h"
c88d4c7b 93
8350b3dc 94int unprivileged_userns_apparmor_policy = 1;
c88d4c7b 95
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96/* Note: mode names must be unique in the first character because of
97 * modechrs used to print modes on compound labels on some interfaces
98 */
0d259f04 99const char *const aa_profile_mode_names[] = {
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100 "enforce",
101 "complain",
102 "kill",
03816507 103 "unconfined",
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104};
105
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106/**
107 * aa_free_data - free a data blob
108 * @ptr: data to free
109 * @arg: unused
110 */
111static void aa_free_data(void *ptr, void *arg)
112{
113 struct aa_data *data = ptr;
114
115 kzfree(data->data);
116 kzfree(data->key);
117 kzfree(data);
118}
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119
120/**
80594fc2 121 * __add_profile - add a profiles to list and label tree
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122 * @list: list to add it to (NOT NULL)
123 * @profile: the profile to add (NOT NULL)
124 *
125 * refcount @profile, should be put by __list_remove_profile
126 *
127 * Requires: namespace lock be held, or list not be shared
128 */
80594fc2 129static void __add_profile(struct list_head *list, struct aa_profile *profile)
c88d4c7b 130{
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131 struct aa_label *l;
132
133 AA_BUG(!list);
134 AA_BUG(!profile);
135 AA_BUG(!profile->ns);
136 AA_BUG(!mutex_is_locked(&profile->ns->lock));
137
01e2b670 138 list_add_rcu(&profile->base.list, list);
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139 /* get list reference */
140 aa_get_profile(profile);
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141 l = aa_label_insert(&profile->ns->labels, &profile->label);
142 AA_BUG(l != &profile->label);
143 aa_put_label(l);
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144}
145
146/**
147 * __list_remove_profile - remove a profile from the list it is on
148 * @profile: the profile to remove (NOT NULL)
149 *
150 * remove a profile from the list, warning generally removal should
151 * be done with __replace_profile as most profile removals are
152 * replacements to the unconfined profile.
153 *
154 * put @profile list refcount
155 *
156 * Requires: namespace lock be held, or list not have been live
157 */
158static void __list_remove_profile(struct aa_profile *profile)
159{
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160 AA_BUG(!profile);
161 AA_BUG(!profile->ns);
162 AA_BUG(!mutex_is_locked(&profile->ns->lock));
163
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164 list_del_rcu(&profile->base.list);
165 aa_put_profile(profile);
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166}
167
80594fc2 168void __aa_profile_list_release(struct list_head *head);
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169
170/**
171 * __remove_profile - remove old profile, and children
172 * @profile: profile to be replaced (NOT NULL)
173 *
174 * Requires: namespace list lock be held, or list not be shared
175 */
176static void __remove_profile(struct aa_profile *profile)
177{
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178 AA_BUG(!profile);
179 AA_BUG(!profile->ns);
180 AA_BUG(!mutex_is_locked(&profile->ns->lock));
181
c88d4c7b 182 /* release any children lists first */
80594fc2 183 __aa_profile_list_release(&profile->base.profiles);
c88d4c7b 184 /* released by free_profile */
80594fc2 185 aa_label_remove(&profile->label);
0d259f04 186 __aa_fs_profile_rmdir(profile);
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187 __list_remove_profile(profile);
188}
189
190/**
80594fc2 191 * __aa_profile_list_release - remove all profiles on the list and put refs
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192 * @head: list of profiles (NOT NULL)
193 *
194 * Requires: namespace lock be held
195 */
80594fc2 196void __aa_profile_list_release(struct list_head *head)
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197{
198 struct aa_profile *profile, *tmp;
199 list_for_each_entry_safe(profile, tmp, head, base.list)
200 __remove_profile(profile);
201}
202
77b071b3 203
c88d4c7b 204/**
8651e1d6 205 * aa_free_profile - free a profile
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206 * @profile: the profile to free (MAYBE NULL)
207 *
208 * Free a profile, its hats and null_profile. All references to the profile,
209 * its hats and null_profile must have been put.
210 *
211 * If the profile was referenced from a task context, free_profile() will
212 * be called from an rcu callback routine, so we must not sleep here.
213 */
8651e1d6 214void aa_free_profile(struct aa_profile *profile)
c88d4c7b 215{
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216 struct rhashtable *rht;
217
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218 AA_DEBUG("%s(%p)\n", __func__, profile);
219
220 if (!profile)
221 return;
222
c88d4c7b 223 /* free children profiles */
80594fc2 224 aa_policy_destroy(&profile->base);
01e2b670 225 aa_put_profile(rcu_access_pointer(profile->parent));
c88d4c7b 226
80594fc2 227 aa_put_ns(profile->ns);
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228 kzfree(profile->rename);
229
230 aa_free_file_rules(&profile->file);
231 aa_free_cap_rules(&profile->caps);
80594fc2 232 aa_free_net_rules(&profile->net);
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233 aa_free_rlimit_rules(&profile->rlimits);
234
0d259f04 235 kzfree(profile->dirname);
c88d4c7b 236 aa_put_dfa(profile->xmatch);
ad5ff3db 237 aa_put_dfa(profile->policy.dfa);
c88d4c7b 238
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239 if (profile->data) {
240 rht = profile->data;
241 profile->data = NULL;
242 rhashtable_free_and_destroy(rht, aa_free_data, NULL);
243 kzfree(rht);
244 }
245
5cb3e91e 246 kzfree(profile->hash);
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247 aa_put_loaddata(profile->rawdata);
248
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249 kzfree(profile);
250}
251
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252/**
253 * aa_alloc_profile - allocate, initialize and return a new profile
254 * @hname: name of the profile (NOT NULL)
80594fc2 255 * @gfp: allocation type
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256 *
257 * Returns: refcount profile or NULL on failure
258 */
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259struct aa_profile *aa_alloc_profile(const char *hname, struct aa_proxy *proxy,
260 gfp_t gfp)
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261{
262 struct aa_profile *profile;
263
264 /* freed by free_profile - usually through aa_put_profile */
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265 profile = kzalloc(sizeof(*profile) + sizeof (struct aa_profile *) * 2,
266 gfp);
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267 if (!profile)
268 return NULL;
269
80594fc2 270 if (!aa_policy_init(&profile->base, NULL, hname, gfp))
77b071b3 271 goto fail;
80594fc2 272 if (!aa_label_init(&profile->label, 1))
77b071b3 273 goto fail;
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274
275 /* update being set needed by fs interface */
276 if (!proxy) {
277 proxy = aa_alloc_proxy(&profile->label, gfp);
278 if (!proxy)
279 goto fail;
280 } else
281 aa_get_proxy(proxy);
282 profile->label.proxy = proxy;
283
284 profile->label.hname = profile->base.hname;
285 profile->label.flags |= FLAG_PROFILE;
286 profile->label.vec[0] = profile;
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287
288 /* refcount released by caller */
289 return profile;
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290
291fail:
80594fc2 292 aa_free_profile(profile);
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293
294 return NULL;
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295}
296
297/**
80594fc2 298 * aa_null_profile - create or find a null-X learning profile
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299 * @parent: profile that caused this profile to be created (NOT NULL)
300 * @hat: true if the null- learning profile is a hat
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301 * @base: name to base the null profile off of
302 * @gfp: type of allocation
4da05cc0 303 *
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304 * Find/Create a null- complain mode profile used in learning mode. The
305 * name of the profile is unique and follows the format of parent//null-XXX.
306 * where XXX is based on the @name or if that fails or is not supplied
307 * a unique number
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308 *
309 * null profiles are added to the profile list but the list does not
310 * hold a count on them so that they are automatically released when
311 * not in use.
312 *
313 * Returns: new refcounted profile else NULL on failure
314 */
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315struct aa_profile *aa_null_profile(struct aa_profile *parent, bool hat,
316 const char *base, gfp_t gfp)
4da05cc0 317{
80594fc2 318 struct aa_profile *profile;
4da05cc0 319 char *name;
4da05cc0 320
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321 AA_BUG(!parent);
322
323 if (base) {
324 name = kmalloc(strlen(parent->base.hname) + 8 + strlen(base),
325 gfp);
326 if (name) {
327 sprintf(name, "%s//null-%s", parent->base.hname, base);
328 goto name;
329 }
330 /* fall through to try shorter uniq */
331 }
332
333 name = kmalloc(strlen(parent->base.hname) + 2 + 7 + 8, gfp);
4da05cc0 334 if (!name)
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335 return NULL;
336 sprintf(name, "%s//null-%x", parent->base.hname,
337 atomic_inc_return(&parent->ns->uniq_null));
4da05cc0 338
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339name:
340 /* lookup to see if this is a dup creation */
341 profile = aa_find_child(parent, basename(name));
342 if (profile)
343 goto out;
344
345 profile = aa_alloc_profile(name, NULL, gfp);
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346 if (!profile)
347 goto fail;
348
349 profile->mode = APPARMOR_COMPLAIN;
80594fc2 350 profile->label.flags |= FLAG_NULL;
4da05cc0 351 if (hat)
80594fc2 352 profile->label.flags |= FLAG_HAT;
c0b46bf1 353 profile->path_flags = parent->path_flags;
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354
355 /* released on free_profile */
01e2b670 356 rcu_assign_pointer(profile->parent, aa_get_profile(parent));
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357 profile->ns = aa_get_ns(parent->ns);
358 profile->file.dfa = aa_get_dfa(nulldfa);
359 profile->policy.dfa = aa_get_dfa(nulldfa);
4da05cc0 360
01e2b670 361 mutex_lock(&profile->ns->lock);
80594fc2 362 __add_profile(&parent->base.profiles, profile);
01e2b670 363 mutex_unlock(&profile->ns->lock);
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364
365 /* refcount released by caller */
80594fc2
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366out:
367 kfree(name);
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368 return profile;
369
370fail:
80594fc2 371 aa_free_profile(profile);
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372 return NULL;
373}
374
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375/**
376 * aa_setup_default_label - create the initial default label
377 */
378struct aa_label *aa_setup_default_label(void)
379{
380 struct aa_profile *profile = aa_alloc_profile("default", NULL,
381 GFP_KERNEL);
382 if (!profile)
383 return NULL;
384
385 /* the default profile pretends to be unconfined until it is replaced */
386 profile->label.flags |= FLAG_IX_ON_NAME_ERROR | FLAG_UNCONFINED;
387 profile->mode = APPARMOR_UNCONFINED;
388
389 profile->ns = aa_get_ns(root_ns);
390
391 __add_profile(&root_ns->base.profiles, profile);
392
393 return &profile->label;
394}
395
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396/* TODO: profile accounting - setup in remove */
397
398/**
399 * __find_child - find a profile on @head list with a name matching @name
400 * @head: list to search (NOT NULL)
401 * @name: name of profile (NOT NULL)
402 *
01e2b670 403 * Requires: rcu_read_lock be held
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404 *
405 * Returns: unrefcounted profile ptr, or NULL if not found
406 */
407static struct aa_profile *__find_child(struct list_head *head, const char *name)
408{
409 return (struct aa_profile *)__policy_find(head, name);
410}
411
412/**
413 * __strn_find_child - find a profile on @head list using substring of @name
414 * @head: list to search (NOT NULL)
415 * @name: name of profile (NOT NULL)
416 * @len: length of @name substring to match
417 *
01e2b670 418 * Requires: rcu_read_lock be held
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419 *
420 * Returns: unrefcounted profile ptr, or NULL if not found
421 */
422static struct aa_profile *__strn_find_child(struct list_head *head,
423 const char *name, int len)
424{
425 return (struct aa_profile *)__policy_strn_find(head, name, len);
426}
427
428/**
429 * aa_find_child - find a profile by @name in @parent
430 * @parent: profile to search (NOT NULL)
431 * @name: profile name to search for (NOT NULL)
432 *
433 * Returns: a refcounted profile or NULL if not found
434 */
435struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name)
436{
437 struct aa_profile *profile;
438
01e2b670 439 rcu_read_lock();
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440 do {
441 profile = __find_child(&parent->base.profiles, name);
442 } while (profile && !aa_get_profile_not0(profile));
01e2b670 443 rcu_read_unlock();
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444
445 /* refcount released by caller */
446 return profile;
447}
448
449/**
450 * __lookup_parent - lookup the parent of a profile of name @hname
451 * @ns: namespace to lookup profile in (NOT NULL)
452 * @hname: hierarchical profile name to find parent of (NOT NULL)
453 *
454 * Lookups up the parent of a fully qualified profile name, the profile
455 * that matches hname does not need to exist, in general this
456 * is used to load a new profile.
457 *
01e2b670 458 * Requires: rcu_read_lock be held
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459 *
460 * Returns: unrefcounted policy or NULL if not found
461 */
80594fc2 462static struct aa_policy *__lookup_parent(struct aa_ns *ns, const char *hname)
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463{
464 struct aa_policy *policy;
465 struct aa_profile *profile = NULL;
466 char *split;
467
468 policy = &ns->base;
469
470 for (split = strstr(hname, "//"); split;) {
471 profile = __strn_find_child(&policy->profiles, hname,
472 split - hname);
473 if (!profile)
474 return NULL;
475 policy = &profile->base;
476 hname = split + 2;
477 split = strstr(hname, "//");
478 }
479 if (!profile)
480 return &ns->base;
481 return &profile->base;
482}
483
484/**
80594fc2 485 * __lookupn_profile - lookup the profile matching @hname
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486 * @base: base list to start looking up profile name from (NOT NULL)
487 * @hname: hierarchical profile name (NOT NULL)
80594fc2 488 * @n: length of @hname
c88d4c7b 489 *
01e2b670 490 * Requires: rcu_read_lock be held
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491 *
492 * Returns: unrefcounted profile pointer or NULL if not found
493 *
494 * Do a relative name lookup, recursing through profile tree.
495 */
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496static struct aa_profile *__lookupn_profile(struct aa_policy *base,
497 const char *hname, size_t n)
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498{
499 struct aa_profile *profile = NULL;
80594fc2 500 const char *split;
c88d4c7b 501
80594fc2
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502 for (split = strnstr(hname, "//", n); split;
503 split = strnstr(hname, "//", n)) {
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504 profile = __strn_find_child(&base->profiles, hname,
505 split - hname);
506 if (!profile)
507 return NULL;
508
509 base = &profile->base;
80594fc2 510 n -= split + 2 - hname;
c88d4c7b 511 hname = split + 2;
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512 }
513
80594fc2
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514 if (n)
515 return __strn_find_child(&base->profiles, hname, n);
516 return NULL;
517}
c88d4c7b 518
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519static struct aa_profile *__lookup_profile(struct aa_policy *base,
520 const char *hname)
521{
522 return __lookupn_profile(base, hname, strlen(hname));
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523}
524
525/**
526 * aa_lookup_profile - find a profile by its full or partial name
527 * @ns: the namespace to start from (NOT NULL)
528 * @hname: name to do lookup on. Does not contain namespace prefix (NOT NULL)
80594fc2 529 * @n: size of @hname
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530 *
531 * Returns: refcounted profile or NULL if not found
532 */
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533struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
534 size_t n)
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535{
536 struct aa_profile *profile;
537
01e2b670
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538 rcu_read_lock();
539 do {
80594fc2 540 profile = __lookupn_profile(&ns->base, hname, n);
01e2b670
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541 } while (profile && !aa_get_profile_not0(profile));
542 rcu_read_unlock();
c88d4c7b 543
bf83208e 544 /* the unconfined profile is not in the regular profile list */
80594fc2 545 if (!profile && strncmp(hname, "unconfined", n) == 0)
fa2ac468 546 profile = aa_get_newest_profile(ns->unconfined);
bf83208e 547
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548 /* refcount released by caller */
549 return profile;
550}
551
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552struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *hname)
553{
554 return aa_lookupn_profile(ns, hname, strlen(hname));
555}
556
557struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
558 const char *fqname, size_t n)
559{
560 struct aa_profile *profile;
561 struct aa_ns *ns;
562 const char *name, *ns_name;
563 size_t ns_len;
564
565 name = aa_splitn_fqname(fqname, n, &ns_name, &ns_len);
566 if (ns_name) {
567 ns = aa_findn_ns(labels_ns(base), ns_name, ns_len);
568 if (!ns)
569 return NULL;
570 } else
571 ns = aa_get_ns(labels_ns(base));
572
573 if (name)
574 profile = aa_lookupn_profile(ns, name, n - (name - fqname));
575 else if (ns)
576 /* default profile for ns, currently unconfined */
577 profile = aa_get_newest_profile(ns->unconfined);
578 else
579 profile = NULL;
580 aa_put_ns(ns);
581
582 return profile;
583}
584
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585/**
586 * replacement_allowed - test to see if replacement is allowed
587 * @profile: profile to test if it can be replaced (MAYBE NULL)
588 * @noreplace: true if replacement shouldn't be allowed but addition is okay
589 * @info: Returns - info about why replacement failed (NOT NULL)
590 *
591 * Returns: %0 if replacement allowed else error code
592 */
593static int replacement_allowed(struct aa_profile *profile, int noreplace,
594 const char **info)
595{
596 if (profile) {
80594fc2 597 if (profile->label.flags & FLAG_IMMUTIBLE) {
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598 *info = "cannot replace immutible profile";
599 return -EPERM;
600 } else if (noreplace) {
601 *info = "profile already exists";
602 return -EEXIST;
603 }
604 }
605 return 0;
606}
607
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608/* audit callback for net specific fields */
609static void audit_cb(struct audit_buffer *ab, void *va)
610{
611 struct common_audit_data *sa = va;
612
613 if (aad(sa)->iface.ns) {
614 audit_log_format(ab, " ns=");
615 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
616 }
617}
618
c88d4c7b 619/**
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620 * audit_policy - Do auditing of policy changes
621 * @label: label to check if it can manage policy
c88d4c7b 622 * @op: policy operation being performed
80594fc2 623 * @profile: name of profile being manipulated (NOT NULL)
c88d4c7b
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624 * @info: any extra information to be audited (MAYBE NULL)
625 * @error: error code
626 *
627 * Returns: the error to be returned after audit is done
628 */
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JJ
629static int audit_policy(struct aa_label *label, const char *op,
630 const char *ns_name, const char *name,
631 const char *info, int error)
c88d4c7b 632{
80594fc2
JJ
633 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, op);
634 // aad(&sa)->op = op;
635 aad(&sa)->iface.ns = ns_name;
636 aad(&sa)->name = name;
637 aad(&sa)->info = info;
638 aad(&sa)->error = error;
639 aad(&sa)->label = label;
640
641 aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, audit_cb);
642
643 return error;
c88d4c7b
JJ
644}
645
11141223
JJ
646/**
647 * policy_view_capable - check if viewing policy in at @ns is allowed
648 * ns: namespace being viewed by current task (may be NULL)
649 * Returns: true if viewing policy is allowed
650 *
651 * If @ns is NULL then the namespace being viewed is assumed to be the
652 * tasks current namespace.
653 */
654bool policy_view_capable(struct aa_ns *ns)
58acf9d9
JJ
655{
656 struct user_namespace *user_ns = current_user_ns();
11141223 657 struct aa_ns *view_ns = aa_get_current_ns();
451dc704
JJ
658 bool root_in_user_ns = uid_eq(current_euid(), make_kuid(user_ns, 0)) ||
659 in_egroup_p(make_kgid(user_ns, 0));
58acf9d9 660 bool response = false;
11141223
JJ
661 if (!ns)
662 ns = view_ns;
58acf9d9 663
11141223 664 if (root_in_user_ns && aa_ns_visible(view_ns, ns, true) &&
8ccc1769 665 (user_ns == &init_user_ns ||
590a154b 666 (unprivileged_userns_apparmor_policy != 0 &&
11141223 667 user_ns->level == view_ns->level)))
8ccc1769 668 response = true;
11141223 669 aa_put_ns(view_ns);
8ccc1769
TH
670
671 return response;
672}
673
11141223 674bool policy_admin_capable(struct aa_ns *ns)
8ccc1769
TH
675{
676 struct user_namespace *user_ns = current_user_ns();
451dc704 677 bool capable = ns_capable(user_ns, CAP_MAC_ADMIN);
8ccc1769 678
451dc704
JJ
679 AA_DEBUG("cap_mac_admin? %d\n", capable);
680 AA_DEBUG("policy locked? %d\n", aa_g_lock_policy);
58acf9d9 681
11141223 682 return policy_view_capable(ns) && capable && !aa_g_lock_policy;
58acf9d9
JJ
683}
684
c88d4c7b
JJ
685/**
686 * aa_may_manage_policy - can the current task manage policy
80594fc2 687 * @label: label to check if it can manage policy
c88d4c7b
JJ
688 * @op: the policy manipulation operation being done
689 *
80594fc2 690 * Returns: 0 if the task is allowed to manipulate policy else error
c88d4c7b 691 */
11141223 692int aa_may_manage_policy(struct aa_label *label, struct aa_ns *ns, u32 mask)
c88d4c7b 693{
80594fc2
JJ
694 const char *op;
695
696 if (mask & AA_MAY_REMOVE_POLICY)
697 op = OP_PROF_RM;
698 else if (mask & AA_MAY_REPLACE_POLICY)
699 op = OP_PROF_REPL;
700 else
701 op = OP_PROF_LOAD;
702
c88d4c7b 703 /* check if loading policy is locked out */
80594fc2
JJ
704 if (aa_g_lock_policy)
705 return audit_policy(label, op, NULL, NULL, "policy_locked",
706 -EACCES);
c88d4c7b 707
11141223 708 if (!policy_admin_capable(ns))
80594fc2
JJ
709 return audit_policy(label, op, NULL, NULL, "not policy admin",
710 -EACCES);
c88d4c7b 711
80594fc2
JJ
712 /* TODO: add fine grained mediation of policy loads */
713 return 0;
c88d4c7b
JJ
714}
715
dd51c848
JJ
716static struct aa_profile *__list_lookup_parent(struct list_head *lh,
717 struct aa_profile *profile)
718{
80594fc2 719 const char *base = basename(profile->base.hname);
dd51c848
JJ
720 long len = base - profile->base.hname;
721 struct aa_load_ent *ent;
722
723 /* parent won't have trailing // so remove from len */
724 if (len <= 2)
725 return NULL;
726 len -= 2;
727
728 list_for_each_entry(ent, lh, list) {
729 if (ent->new == profile)
730 continue;
731 if (strncmp(ent->new->base.hname, profile->base.hname, len) ==
732 0 && ent->new->base.hname[len] == 0)
733 return ent->new;
734 }
735
736 return NULL;
737}
738
739/**
740 * __replace_profile - replace @old with @new on a list
741 * @old: profile to be replaced (NOT NULL)
742 * @new: profile to replace @old with (NOT NULL)
743 *
744 * Will duplicate and refcount elements that @new inherits from @old
745 * and will inherit @old children.
746 *
747 * refcount @new for list, put @old list refcount
748 *
749 * Requires: namespace list lock be held, or list not be shared
750 */
80594fc2 751static void __replace_profile(struct aa_profile *old, struct aa_profile *new)
dd51c848
JJ
752{
753 struct aa_profile *child, *tmp;
754
755 if (!list_empty(&old->base.profiles)) {
756 LIST_HEAD(lh);
01e2b670 757 list_splice_init_rcu(&old->base.profiles, &lh, synchronize_rcu);
dd51c848
JJ
758
759 list_for_each_entry_safe(child, tmp, &lh, base.list) {
760 struct aa_profile *p;
761
762 list_del_init(&child->base.list);
763 p = __find_child(&new->base.profiles, child->base.name);
764 if (p) {
765 /* @p replaces @child */
80594fc2 766 __replace_profile(child, p);
dd51c848
JJ
767 continue;
768 }
769
770 /* inherit @child and its children */
771 /* TODO: update hname of inherited children */
772 /* list refcount transferred to @new */
0d259f04 773 p = aa_deref_parent(child);
01e2b670
JJ
774 rcu_assign_pointer(child->parent, aa_get_profile(new));
775 list_add_rcu(&child->base.list, &new->base.profiles);
776 aa_put_profile(p);
dd51c848
JJ
777 }
778 }
779
01e2b670 780 if (!rcu_access_pointer(new->parent)) {
0d259f04 781 struct aa_profile *parent = aa_deref_parent(old);
01e2b670
JJ
782 rcu_assign_pointer(new->parent, aa_get_profile(parent));
783 }
80594fc2
JJ
784 aa_label_replace(&old->label, &new->label);
785 /* migrate dents must come after label replacement b/c update */
0d259f04 786 __aa_fs_profile_migrate_dents(old, new);
dd51c848
JJ
787
788 if (list_empty(&new->base.list)) {
789 /* new is not on a list already */
01e2b670 790 list_replace_rcu(&old->base.list, &new->base.list);
dd51c848
JJ
791 aa_get_profile(new);
792 aa_put_profile(old);
793 } else
794 __list_remove_profile(old);
795}
796
797/**
798 * __lookup_replace - lookup replacement information for a profile
799 * @ns - namespace the lookup occurs in
800 * @hname - name of profile to lookup
801 * @noreplace - true if not replacing an existing profile
802 * @p - Returns: profile to be replaced
803 * @info - Returns: info string on why lookup failed
804 *
805 * Returns: profile to replace (no ref) on success else ptr error
806 */
80594fc2 807static int __lookup_replace(struct aa_ns *ns, const char *hname,
dd51c848
JJ
808 bool noreplace, struct aa_profile **p,
809 const char **info)
810{
811 *p = aa_get_profile(__lookup_profile(&ns->base, hname));
812 if (*p) {
813 int error = replacement_allowed(*p, noreplace, info);
814 if (error) {
815 *info = "profile can not be replaced";
816 return error;
817 }
818 }
819
820 return 0;
821}
822
80594fc2
JJ
823static void share_name(struct aa_profile *old, struct aa_profile *new)
824{
825 aa_put_str(new->base.hname);
826 aa_get_str(old->base.hname);
827 new->base.hname = old->base.hname;
828 new->base.name = old->base.name;
829 new->label.hname = old->label.hname;
830}
831
832/* Update to newest version of parent after previous replacements
833 * Returns: unrefcount newest version of parent
834 */
835static struct aa_profile *update_to_newest_parent(struct aa_profile *new)
836{
837 struct aa_profile *parent, *newest;
838 parent = rcu_dereference_protected(new->parent,
839 mutex_is_locked(&new->ns->lock));
840 newest = aa_get_newest_profile(parent);
841
842 /* parent replaced in this atomic set? */
843 if (newest != parent) {
844 aa_put_profile(parent);
845 rcu_assign_pointer(new->parent, newest);
846 } else
847 aa_put_profile(newest);
848
849 return newest;
850}
851
c88d4c7b
JJ
852/**
853 * aa_replace_profiles - replace profile(s) on the profile list
0acae0c2 854 * @view: namespace load is viewed from
80594fc2
JJ
855 * @label: label that is attempting to load/replace policy
856 * @mask: permission mask
c88d4c7b 857 * @udata: serialized data stream (NOT NULL)
c88d4c7b
JJ
858 *
859 * unpack and replace a profile on the profile list and uses of that profile
80594fc2 860 * by any aa_task_ctx. If the profile does not exist on the profile list
c88d4c7b
JJ
861 * it is added.
862 *
863 * Returns: size of data consumed else error code on failure.
864 */
0acae0c2
JJ
865ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_label *label,
866 u32 mask, struct aa_loaddata *udata)
c88d4c7b 867{
bf15cf0c 868 const char *ns_name, *info = NULL;
80594fc2 869 struct aa_ns *ns = NULL;
dd51c848 870 struct aa_load_ent *ent, *tmp;
80594fc2
JJ
871 const char *op = mask & AA_MAY_REPLACE_POLICY ? OP_PROF_REPL : OP_PROF_LOAD;
872 ssize_t count, error;
873
dd51c848 874 LIST_HEAD(lh);
c88d4c7b
JJ
875
876 /* released below */
3b8ad847 877 error = aa_unpack(udata, &lh, &ns_name);
dd51c848
JJ
878 if (error)
879 goto out;
c88d4c7b 880
80594fc2
JJ
881 /* ensure that profiles are all for the same ns
882 * TODO: update locking to remove this constaint. All profiles in
883 * the load set must succeed as a set or the load will
884 * fail. Sort ent list and take ns locks in hierarchy order
885 */
886 count = 0;
887 list_for_each_entry(ent, &lh, list) {
888 if (ns_name) {
889 if (ent->ns_name &&
890 strcmp(ent->ns_name, ns_name) != 0) {
891 info = "policy load has mixed namespaces";
892 error = -EACCES;
893 goto fail;
894 }
895 } else if (ent->ns_name) {
896 if (count) {
897 info = "policy load has mixed namespaces";
898 error = -EACCES;
899 goto fail;
900 }
901 ns_name = ent->ns_name;
902 } else
903 count++;
c88d4c7b 904 }
80594fc2 905 if (ns_name) {
0acae0c2 906 ns = aa_prepare_ns(view, ns_name);
ec25af4b 907 if (IS_ERR(ns)) {
80594fc2 908 info = "failed to prepare namespace";
ec25af4b
JJ
909 error = PTR_ERR(ns);
910 ns = NULL;
80594fc2
JJ
911 goto fail;
912 }
913 } else
0acae0c2 914 ns = aa_get_ns(view);
c88d4c7b 915
01e2b670 916 mutex_lock(&ns->lock);
dd51c848
JJ
917 /* setup parent and ns info */
918 list_for_each_entry(ent, &lh, list) {
919 struct aa_policy *policy;
80594fc2 920
3b8ad847 921 ent->new->rawdata = aa_get_loaddata(udata);
80594fc2
JJ
922 error = __lookup_replace(ns, ent->new->base.hname,
923 !(mask & AA_MAY_REPLACE_POLICY),
dd51c848
JJ
924 &ent->old, &info);
925 if (error)
926 goto fail_lock;
927
928 if (ent->new->rename) {
929 error = __lookup_replace(ns, ent->new->rename,
80594fc2
JJ
930 !(mask & AA_MAY_REPLACE_POLICY),
931 &ent->rename, &info);
dd51c848
JJ
932 if (error)
933 goto fail_lock;
c88d4c7b 934 }
c88d4c7b 935
dd51c848 936 /* released when @new is freed */
80594fc2 937 ent->new->ns = aa_get_ns(ns);
dd51c848
JJ
938
939 if (ent->old || ent->rename)
940 continue;
941
942 /* no ref on policy only use inside lock */
943 policy = __lookup_parent(ns, ent->new->base.hname);
944 if (!policy) {
945 struct aa_profile *p;
946 p = __list_lookup_parent(&lh, ent->new);
947 if (!p) {
948 error = -ENOENT;
949 info = "parent does not exist";
dd51c848
JJ
950 goto fail_lock;
951 }
01e2b670
JJ
952 rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
953 } else if (policy != &ns->base) {
dd51c848 954 /* released on profile replacement or free_profile */
01e2b670
JJ
955 struct aa_profile *p = (struct aa_profile *) policy;
956 rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
957 }
dd51c848 958 }
c88d4c7b 959
0d259f04
JJ
960 /* create new fs entries for introspection if needed */
961 list_for_each_entry(ent, &lh, list) {
80594fc2 962 if (!ent->old) {
0d259f04
JJ
963 struct dentry *parent;
964 if (rcu_access_pointer(ent->new->parent)) {
965 struct aa_profile *p;
966 p = aa_deref_parent(ent->new);
967 parent = prof_child_dir(p);
968 } else
969 parent = ns_subprofs_dir(ent->new->ns);
970 error = __aa_fs_profile_mkdir(ent->new, parent);
971 }
972
973 if (error) {
80594fc2 974 info = "failed to create";
0d259f04
JJ
975 goto fail_lock;
976 }
977 }
978
979 /* Done with checks that may fail - do actual replacement */
dd51c848
JJ
980 list_for_each_entry_safe(ent, tmp, &lh, list) {
981 list_del_init(&ent->list);
982 op = (!ent->old && !ent->rename) ? OP_PROF_LOAD : OP_PROF_REPL;
983
80594fc2 984 audit_policy(label, op, ns_name, ent->new->base.hname, NULL, error);
dd51c848
JJ
985
986 if (ent->old) {
80594fc2
JJ
987 share_name(ent->old, ent->new);
988 __replace_profile(ent->old, ent->new);
989 if (ent->rename)
990 __replace_profile(ent->rename, ent->new);
dd51c848 991 } else if (ent->rename) {
80594fc2
JJ
992 /* TODO: case not actually supported yet */
993 ;
0d259f04 994 } else {
80594fc2
JJ
995 struct list_head *lh;
996 if (rcu_access_pointer(ent->new->parent)) {
997 struct aa_profile *parent;
998 parent = update_to_newest_parent(ent->new);
999 lh = &parent->base.profiles;
1000 } else
1001 lh = &ns->base.profiles;
1002 __add_profile(lh, ent->new);
0d259f04 1003 }
dd51c848 1004 aa_load_ent_free(ent);
c88d4c7b 1005 }
80594fc2 1006 __aa_labelset_update_subtree(ns);
28a99263 1007 __aa_bump_ns_revision(ns);
01e2b670 1008 mutex_unlock(&ns->lock);
c88d4c7b
JJ
1009
1010out:
80594fc2 1011 aa_put_ns(ns);
dd51c848 1012
c88d4c7b
JJ
1013 if (error)
1014 return error;
3b8ad847 1015 return udata->size;
c88d4c7b 1016
dd51c848 1017fail_lock:
01e2b670 1018 mutex_unlock(&ns->lock);
dd51c848 1019
bf15cf0c
JJ
1020 /* audit cause of failure */
1021 op = (!ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
80594fc2
JJ
1022fail:
1023 audit_policy(label, op, ns_name, ent->new->base.hname, info, error);
bf15cf0c
JJ
1024 /* audit status that rest of profiles in the atomic set failed too */
1025 info = "valid profile in failed atomic policy load";
1026 list_for_each_entry(tmp, &lh, list) {
1027 if (tmp == ent) {
1028 info = "unchecked profile in failed atomic policy load";
1029 /* skip entry that caused failure */
1030 continue;
1031 }
1032 op = (!ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
80594fc2 1033 audit_policy(label, op, ns_name, tmp->new->base.hname, info, error);
bf15cf0c 1034 }
dd51c848
JJ
1035 list_for_each_entry_safe(ent, tmp, &lh, list) {
1036 list_del_init(&ent->list);
1037 aa_load_ent_free(ent);
1038 }
1039
c88d4c7b
JJ
1040 goto out;
1041}
1042
1043/**
1044 * aa_remove_profiles - remove profile(s) from the system
0acae0c2 1045 * @view: namespace the remove is being done from
80594fc2 1046 * @label: label attempting to remove policy
c88d4c7b
JJ
1047 * @fqname: name of the profile or namespace to remove (NOT NULL)
1048 * @size: size of the name
1049 *
1050 * Remove a profile or sub namespace from the current namespace, so that
1051 * they can not be found anymore and mark them as replaced by unconfined
1052 *
1053 * NOTE: removing confinement does not restore rlimits to preconfinemnet values
1054 *
1055 * Returns: size of data consume else error code if fails
1056 */
0acae0c2
JJ
1057ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_label *label,
1058 char *fqname, size_t size)
c88d4c7b 1059{
80594fc2 1060 struct aa_ns *root = NULL, *ns = NULL;
c88d4c7b
JJ
1061 struct aa_profile *profile = NULL;
1062 const char *name = fqname, *info = NULL;
80594fc2 1063 char *ns_name = NULL;
c88d4c7b
JJ
1064 ssize_t error = 0;
1065
1066 if (*fqname == 0) {
1067 info = "no profile specified";
1068 error = -ENOENT;
1069 goto fail;
1070 }
1071
0acae0c2 1072 root = view;
c88d4c7b
JJ
1073
1074 if (fqname[0] == ':') {
c88d4c7b 1075 name = aa_split_fqname(fqname, &ns_name);
41d1b3e8 1076 /* released below */
80594fc2 1077 ns = aa_find_ns(root, ns_name);
41d1b3e8
JJ
1078 if (!ns) {
1079 info = "namespace does not exist";
1080 error = -ENOENT;
1081 goto fail;
c88d4c7b
JJ
1082 }
1083 } else
1084 /* released below */
80594fc2 1085 ns = aa_get_ns(root);
c88d4c7b 1086
c88d4c7b
JJ
1087 if (!name) {
1088 /* remove namespace - can only happen if fqname[0] == ':' */
01e2b670 1089 mutex_lock(&ns->parent->lock);
80594fc2 1090 __aa_remove_ns(ns);
28a99263 1091 __aa_bump_ns_revision(ns);
01e2b670 1092 mutex_unlock(&ns->parent->lock);
c88d4c7b
JJ
1093 } else {
1094 /* remove profile */
01e2b670 1095 mutex_lock(&ns->lock);
c88d4c7b
JJ
1096 profile = aa_get_profile(__lookup_profile(&ns->base, name));
1097 if (!profile) {
1098 error = -ENOENT;
1099 info = "profile does not exist";
1100 goto fail_ns_lock;
1101 }
1102 name = profile->base.hname;
1103 __remove_profile(profile);
80594fc2 1104 __aa_labelset_update_subtree(ns);
28a99263 1105 __aa_bump_ns_revision(ns);
01e2b670 1106 mutex_unlock(&ns->lock);
c88d4c7b 1107 }
c88d4c7b
JJ
1108
1109 /* don't fail removal if audit fails */
80594fc2 1110 (void) audit_policy(label, OP_PROF_RM, ns_name, name, info, error);
20920b49 1111 aa_put_ns(ns);
c88d4c7b
JJ
1112 aa_put_profile(profile);
1113 return size;
1114
1115fail_ns_lock:
01e2b670 1116 mutex_unlock(&ns->lock);
20920b49 1117 aa_put_ns(ns);
c88d4c7b
JJ
1118
1119fail:
80594fc2 1120 (void) audit_policy(label, OP_PROF_RM, ns_name, name, info, error);
c88d4c7b
JJ
1121 return error;
1122}