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