Loading...
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/cred.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
105/**
106 * __add_profile - add a profiles to list and label tree
107 * @list: list to add it to (NOT NULL)
108 * @profile: the profile to add (NOT NULL)
109 *
110 * refcount @profile, should be put by __list_remove_profile
111 *
112 * Requires: namespace lock be held, or list not be shared
113 */
114static void __add_profile(struct list_head *list, struct aa_profile *profile)
115{
116 struct aa_label *l;
117
118 AA_BUG(!list);
119 AA_BUG(!profile);
120 AA_BUG(!profile->ns);
121 AA_BUG(!mutex_is_locked(&profile->ns->lock));
122
123 list_add_rcu(&profile->base.list, list);
124 /* get list reference */
125 aa_get_profile(profile);
126 l = aa_label_insert(&profile->ns->labels, &profile->label);
127 AA_BUG(l != &profile->label);
128 aa_put_label(l);
129}
130
131/**
132 * __list_remove_profile - remove a profile from the list it is on
133 * @profile: the profile to remove (NOT NULL)
134 *
135 * remove a profile from the list, warning generally removal should
136 * be done with __replace_profile as most profile removals are
137 * replacements to the unconfined profile.
138 *
139 * put @profile list refcount
140 *
141 * Requires: namespace lock be held, or list not have been live
142 */
143static void __list_remove_profile(struct aa_profile *profile)
144{
145 AA_BUG(!profile);
146 AA_BUG(!profile->ns);
147 AA_BUG(!mutex_is_locked(&profile->ns->lock));
148
149 list_del_rcu(&profile->base.list);
150 aa_put_profile(profile);
151}
152
153/**
154 * __remove_profile - remove old profile, and children
155 * @profile: profile to be replaced (NOT NULL)
156 *
157 * Requires: namespace list lock be held, or list not be shared
158 */
159static void __remove_profile(struct aa_profile *profile)
160{
161 AA_BUG(!profile);
162 AA_BUG(!profile->ns);
163 AA_BUG(!mutex_is_locked(&profile->ns->lock));
164
165 /* release any children lists first */
166 __aa_profile_list_release(&profile->base.profiles);
167 /* released by free_profile */
168 aa_label_remove(&profile->label);
169 __aafs_profile_rmdir(profile);
170 __list_remove_profile(profile);
171}
172
173/**
174 * __aa_profile_list_release - remove all profiles on the list and put refs
175 * @head: list of profiles (NOT NULL)
176 *
177 * Requires: namespace lock be held
178 */
179void __aa_profile_list_release(struct list_head *head)
180{
181 struct aa_profile *profile, *tmp;
182 list_for_each_entry_safe(profile, tmp, head, base.list)
183 __remove_profile(profile);
184}
185
186/**
187 * aa_free_data - free a data blob
188 * @ptr: data to free
189 * @arg: unused
190 */
191static void aa_free_data(void *ptr, void *arg)
192{
193 struct aa_data *data = ptr;
194
195 kzfree(data->data);
196 kzfree(data->key);
197 kzfree(data);
198}
199
200/**
201 * aa_free_profile - free a profile
202 * @profile: the profile to free (MAYBE NULL)
203 *
204 * Free a profile, its hats and null_profile. All references to the profile,
205 * its hats and null_profile must have been put.
206 *
207 * If the profile was referenced from a task context, free_profile() will
208 * be called from an rcu callback routine, so we must not sleep here.
209 */
210void aa_free_profile(struct aa_profile *profile)
211{
212 struct rhashtable *rht;
213 int i;
214
215 AA_DEBUG("%s(%p)\n", __func__, profile);
216
217 if (!profile)
218 return;
219
220 /* free children profiles */
221 aa_policy_destroy(&profile->base);
222 aa_put_profile(rcu_access_pointer(profile->parent));
223
224 aa_put_ns(profile->ns);
225 kzfree(profile->rename);
226
227 aa_free_file_rules(&profile->file);
228 aa_free_cap_rules(&profile->caps);
229 aa_free_rlimit_rules(&profile->rlimits);
230
231 for (i = 0; i < profile->xattr_count; i++)
232 kzfree(profile->xattrs[i]);
233 kzfree(profile->xattrs);
234 kzfree(profile->dirname);
235 aa_put_dfa(profile->xmatch);
236 aa_put_dfa(profile->policy.dfa);
237
238 if (profile->data) {
239 rht = profile->data;
240 profile->data = NULL;
241 rhashtable_free_and_destroy(rht, aa_free_data, NULL);
242 kzfree(rht);
243 }
244
245 kzfree(profile->hash);
246 aa_put_loaddata(profile->rawdata);
247
248 kzfree(profile);
249}
250
251/**
252 * aa_alloc_profile - allocate, initialize and return a new profile
253 * @hname: name of the profile (NOT NULL)
254 * @gfp: allocation type
255 *
256 * Returns: refcount profile or NULL on failure
257 */
258struct aa_profile *aa_alloc_profile(const char *hname, struct aa_proxy *proxy,
259 gfp_t gfp)
260{
261 struct aa_profile *profile;
262
263 /* freed by free_profile - usually through aa_put_profile */
264 profile = kzalloc(sizeof(*profile) + sizeof(struct aa_profile *) * 2,
265 gfp);
266 if (!profile)
267 return NULL;
268
269 if (!aa_policy_init(&profile->base, NULL, hname, gfp))
270 goto fail;
271 if (!aa_label_init(&profile->label, 1))
272 goto fail;
273
274 /* update being set needed by fs interface */
275 if (!proxy) {
276 proxy = aa_alloc_proxy(&profile->label, gfp);
277 if (!proxy)
278 goto fail;
279 } else
280 aa_get_proxy(proxy);
281 profile->label.proxy = proxy;
282
283 profile->label.hname = profile->base.hname;
284 profile->label.flags |= FLAG_PROFILE;
285 profile->label.vec[0] = profile;
286
287 /* refcount released by caller */
288 return profile;
289
290fail:
291 aa_free_profile(profile);
292
293 return NULL;
294}
295
296/* TODO: profile accounting - setup in remove */
297
298/**
299 * __strn_find_child - find a profile on @head list using substring of @name
300 * @head: list to search (NOT NULL)
301 * @name: name of profile (NOT NULL)
302 * @len: length of @name substring to match
303 *
304 * Requires: rcu_read_lock be held
305 *
306 * Returns: unrefcounted profile ptr, or NULL if not found
307 */
308static struct aa_profile *__strn_find_child(struct list_head *head,
309 const char *name, int len)
310{
311 return (struct aa_profile *)__policy_strn_find(head, name, len);
312}
313
314/**
315 * __find_child - find a profile on @head list with a name matching @name
316 * @head: list to search (NOT NULL)
317 * @name: name of profile (NOT NULL)
318 *
319 * Requires: rcu_read_lock be held
320 *
321 * Returns: unrefcounted profile ptr, or NULL if not found
322 */
323static struct aa_profile *__find_child(struct list_head *head, const char *name)
324{
325 return __strn_find_child(head, name, strlen(name));
326}
327
328/**
329 * aa_find_child - find a profile by @name in @parent
330 * @parent: profile to search (NOT NULL)
331 * @name: profile name to search for (NOT NULL)
332 *
333 * Returns: a refcounted profile or NULL if not found
334 */
335struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name)
336{
337 struct aa_profile *profile;
338
339 rcu_read_lock();
340 do {
341 profile = __find_child(&parent->base.profiles, name);
342 } while (profile && !aa_get_profile_not0(profile));
343 rcu_read_unlock();
344
345 /* refcount released by caller */
346 return profile;
347}
348
349/**
350 * __lookup_parent - lookup the parent of a profile of name @hname
351 * @ns: namespace to lookup profile in (NOT NULL)
352 * @hname: hierarchical profile name to find parent of (NOT NULL)
353 *
354 * Lookups up the parent of a fully qualified profile name, the profile
355 * that matches hname does not need to exist, in general this
356 * is used to load a new profile.
357 *
358 * Requires: rcu_read_lock be held
359 *
360 * Returns: unrefcounted policy or NULL if not found
361 */
362static struct aa_policy *__lookup_parent(struct aa_ns *ns,
363 const char *hname)
364{
365 struct aa_policy *policy;
366 struct aa_profile *profile = NULL;
367 char *split;
368
369 policy = &ns->base;
370
371 for (split = strstr(hname, "//"); split;) {
372 profile = __strn_find_child(&policy->profiles, hname,
373 split - hname);
374 if (!profile)
375 return NULL;
376 policy = &profile->base;
377 hname = split + 2;
378 split = strstr(hname, "//");
379 }
380 if (!profile)
381 return &ns->base;
382 return &profile->base;
383}
384
385/**
386 * __lookupn_profile - lookup the profile matching @hname
387 * @base: base list to start looking up profile name from (NOT NULL)
388 * @hname: hierarchical profile name (NOT NULL)
389 * @n: length of @hname
390 *
391 * Requires: rcu_read_lock be held
392 *
393 * Returns: unrefcounted profile pointer or NULL if not found
394 *
395 * Do a relative name lookup, recursing through profile tree.
396 */
397static struct aa_profile *__lookupn_profile(struct aa_policy *base,
398 const char *hname, size_t n)
399{
400 struct aa_profile *profile = NULL;
401 const char *split;
402
403 for (split = strnstr(hname, "//", n); split;
404 split = strnstr(hname, "//", n)) {
405 profile = __strn_find_child(&base->profiles, hname,
406 split - hname);
407 if (!profile)
408 return NULL;
409
410 base = &profile->base;
411 n -= split + 2 - hname;
412 hname = split + 2;
413 }
414
415 if (n)
416 return __strn_find_child(&base->profiles, hname, n);
417 return NULL;
418}
419
420static struct aa_profile *__lookup_profile(struct aa_policy *base,
421 const char *hname)
422{
423 return __lookupn_profile(base, hname, strlen(hname));
424}
425
426/**
427 * aa_lookup_profile - find a profile by its full or partial name
428 * @ns: the namespace to start from (NOT NULL)
429 * @hname: name to do lookup on. Does not contain namespace prefix (NOT NULL)
430 * @n: size of @hname
431 *
432 * Returns: refcounted profile or NULL if not found
433 */
434struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
435 size_t n)
436{
437 struct aa_profile *profile;
438
439 rcu_read_lock();
440 do {
441 profile = __lookupn_profile(&ns->base, hname, n);
442 } while (profile && !aa_get_profile_not0(profile));
443 rcu_read_unlock();
444
445 /* the unconfined profile is not in the regular profile list */
446 if (!profile && strncmp(hname, "unconfined", n) == 0)
447 profile = aa_get_newest_profile(ns->unconfined);
448
449 /* refcount released by caller */
450 return profile;
451}
452
453struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *hname)
454{
455 return aa_lookupn_profile(ns, hname, strlen(hname));
456}
457
458struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
459 const char *fqname, size_t n)
460{
461 struct aa_profile *profile;
462 struct aa_ns *ns;
463 const char *name, *ns_name;
464 size_t ns_len;
465
466 name = aa_splitn_fqname(fqname, n, &ns_name, &ns_len);
467 if (ns_name) {
468 ns = aa_lookupn_ns(labels_ns(base), ns_name, ns_len);
469 if (!ns)
470 return NULL;
471 } else
472 ns = aa_get_ns(labels_ns(base));
473
474 if (name)
475 profile = aa_lookupn_profile(ns, name, n - (name - fqname));
476 else if (ns)
477 /* default profile for ns, currently unconfined */
478 profile = aa_get_newest_profile(ns->unconfined);
479 else
480 profile = NULL;
481 aa_put_ns(ns);
482
483 return profile;
484}
485
486/**
487 * aa_new_null_profile - create or find a null-X learning profile
488 * @parent: profile that caused this profile to be created (NOT NULL)
489 * @hat: true if the null- learning profile is a hat
490 * @base: name to base the null profile off of
491 * @gfp: type of allocation
492 *
493 * Find/Create a null- complain mode profile used in learning mode. The
494 * name of the profile is unique and follows the format of parent//null-XXX.
495 * where XXX is based on the @name or if that fails or is not supplied
496 * a unique number
497 *
498 * null profiles are added to the profile list but the list does not
499 * hold a count on them so that they are automatically released when
500 * not in use.
501 *
502 * Returns: new refcounted profile else NULL on failure
503 */
504struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
505 const char *base, gfp_t gfp)
506{
507 struct aa_profile *p, *profile;
508 const char *bname;
509 char *name = NULL;
510
511 AA_BUG(!parent);
512
513 if (base) {
514 name = kmalloc(strlen(parent->base.hname) + 8 + strlen(base),
515 gfp);
516 if (name) {
517 sprintf(name, "%s//null-%s", parent->base.hname, base);
518 goto name;
519 }
520 /* fall through to try shorter uniq */
521 }
522
523 name = kmalloc(strlen(parent->base.hname) + 2 + 7 + 8, gfp);
524 if (!name)
525 return NULL;
526 sprintf(name, "%s//null-%x", parent->base.hname,
527 atomic_inc_return(&parent->ns->uniq_null));
528
529name:
530 /* lookup to see if this is a dup creation */
531 bname = basename(name);
532 profile = aa_find_child(parent, bname);
533 if (profile)
534 goto out;
535
536 profile = aa_alloc_profile(name, NULL, gfp);
537 if (!profile)
538 goto fail;
539
540 profile->mode = APPARMOR_COMPLAIN;
541 profile->label.flags |= FLAG_NULL;
542 if (hat)
543 profile->label.flags |= FLAG_HAT;
544 profile->path_flags = parent->path_flags;
545
546 /* released on free_profile */
547 rcu_assign_pointer(profile->parent, aa_get_profile(parent));
548 profile->ns = aa_get_ns(parent->ns);
549 profile->file.dfa = aa_get_dfa(nulldfa);
550 profile->policy.dfa = aa_get_dfa(nulldfa);
551
552 mutex_lock_nested(&profile->ns->lock, profile->ns->level);
553 p = __find_child(&parent->base.profiles, bname);
554 if (p) {
555 aa_free_profile(profile);
556 profile = aa_get_profile(p);
557 } else {
558 __add_profile(&parent->base.profiles, profile);
559 }
560 mutex_unlock(&profile->ns->lock);
561
562 /* refcount released by caller */
563out:
564 kfree(name);
565
566 return profile;
567
568fail:
569 kfree(name);
570 aa_free_profile(profile);
571 return NULL;
572}
573
574/**
575 * replacement_allowed - test to see if replacement is allowed
576 * @profile: profile to test if it can be replaced (MAYBE NULL)
577 * @noreplace: true if replacement shouldn't be allowed but addition is okay
578 * @info: Returns - info about why replacement failed (NOT NULL)
579 *
580 * Returns: %0 if replacement allowed else error code
581 */
582static int replacement_allowed(struct aa_profile *profile, int noreplace,
583 const char **info)
584{
585 if (profile) {
586 if (profile->label.flags & FLAG_IMMUTIBLE) {
587 *info = "cannot replace immutible profile";
588 return -EPERM;
589 } else if (noreplace) {
590 *info = "profile already exists";
591 return -EEXIST;
592 }
593 }
594 return 0;
595}
596
597/* audit callback for net specific fields */
598static void audit_cb(struct audit_buffer *ab, void *va)
599{
600 struct common_audit_data *sa = va;
601
602 if (aad(sa)->iface.ns) {
603 audit_log_format(ab, " ns=");
604 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
605 }
606}
607
608/**
609 * audit_policy - Do auditing of policy changes
610 * @label: label to check if it can manage policy
611 * @op: policy operation being performed
612 * @ns_name: name of namespace being manipulated
613 * @name: name of profile being manipulated (NOT NULL)
614 * @info: any extra information to be audited (MAYBE NULL)
615 * @error: error code
616 *
617 * Returns: the error to be returned after audit is done
618 */
619static int audit_policy(struct aa_label *label, const char *op,
620 const char *ns_name, const char *name,
621 const char *info, int error)
622{
623 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, op);
624
625 aad(&sa)->iface.ns = ns_name;
626 aad(&sa)->name = name;
627 aad(&sa)->info = info;
628 aad(&sa)->error = error;
629 aad(&sa)->label = label;
630
631 aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, audit_cb);
632
633 return error;
634}
635
636/**
637 * policy_view_capable - check if viewing policy in at @ns is allowed
638 * ns: namespace being viewed by current task (may be NULL)
639 * Returns: true if viewing policy is allowed
640 *
641 * If @ns is NULL then the namespace being viewed is assumed to be the
642 * tasks current namespace.
643 */
644bool policy_view_capable(struct aa_ns *ns)
645{
646 struct user_namespace *user_ns = current_user_ns();
647 struct aa_ns *view_ns = aa_get_current_ns();
648 bool root_in_user_ns = uid_eq(current_euid(), make_kuid(user_ns, 0)) ||
649 in_egroup_p(make_kgid(user_ns, 0));
650 bool response = false;
651 if (!ns)
652 ns = view_ns;
653
654 if (root_in_user_ns && aa_ns_visible(view_ns, ns, true) &&
655 (user_ns == &init_user_ns ||
656 (unprivileged_userns_apparmor_policy != 0 &&
657 user_ns->level == view_ns->level)))
658 response = true;
659 aa_put_ns(view_ns);
660
661 return response;
662}
663
664bool policy_admin_capable(struct aa_ns *ns)
665{
666 struct user_namespace *user_ns = current_user_ns();
667 bool capable = ns_capable(user_ns, CAP_MAC_ADMIN);
668
669 AA_DEBUG("cap_mac_admin? %d\n", capable);
670 AA_DEBUG("policy locked? %d\n", aa_g_lock_policy);
671
672 return policy_view_capable(ns) && capable && !aa_g_lock_policy;
673}
674
675/**
676 * aa_may_manage_policy - can the current task manage policy
677 * @label: label to check if it can manage policy
678 * @op: the policy manipulation operation being done
679 *
680 * Returns: 0 if the task is allowed to manipulate policy else error
681 */
682int aa_may_manage_policy(struct aa_label *label, struct aa_ns *ns, u32 mask)
683{
684 const char *op;
685
686 if (mask & AA_MAY_REMOVE_POLICY)
687 op = OP_PROF_RM;
688 else if (mask & AA_MAY_REPLACE_POLICY)
689 op = OP_PROF_REPL;
690 else
691 op = OP_PROF_LOAD;
692
693 /* check if loading policy is locked out */
694 if (aa_g_lock_policy)
695 return audit_policy(label, op, NULL, NULL, "policy_locked",
696 -EACCES);
697
698 if (!policy_admin_capable(ns))
699 return audit_policy(label, op, NULL, NULL, "not policy admin",
700 -EACCES);
701
702 /* TODO: add fine grained mediation of policy loads */
703 return 0;
704}
705
706static struct aa_profile *__list_lookup_parent(struct list_head *lh,
707 struct aa_profile *profile)
708{
709 const char *base = basename(profile->base.hname);
710 long len = base - profile->base.hname;
711 struct aa_load_ent *ent;
712
713 /* parent won't have trailing // so remove from len */
714 if (len <= 2)
715 return NULL;
716 len -= 2;
717
718 list_for_each_entry(ent, lh, list) {
719 if (ent->new == profile)
720 continue;
721 if (strncmp(ent->new->base.hname, profile->base.hname, len) ==
722 0 && ent->new->base.hname[len] == 0)
723 return ent->new;
724 }
725
726 return NULL;
727}
728
729/**
730 * __replace_profile - replace @old with @new on a list
731 * @old: profile to be replaced (NOT NULL)
732 * @new: profile to replace @old with (NOT NULL)
733 * @share_proxy: transfer @old->proxy to @new
734 *
735 * Will duplicate and refcount elements that @new inherits from @old
736 * and will inherit @old children.
737 *
738 * refcount @new for list, put @old list refcount
739 *
740 * Requires: namespace list lock be held, or list not be shared
741 */
742static void __replace_profile(struct aa_profile *old, struct aa_profile *new)
743{
744 struct aa_profile *child, *tmp;
745
746 if (!list_empty(&old->base.profiles)) {
747 LIST_HEAD(lh);
748 list_splice_init_rcu(&old->base.profiles, &lh, synchronize_rcu);
749
750 list_for_each_entry_safe(child, tmp, &lh, base.list) {
751 struct aa_profile *p;
752
753 list_del_init(&child->base.list);
754 p = __find_child(&new->base.profiles, child->base.name);
755 if (p) {
756 /* @p replaces @child */
757 __replace_profile(child, p);
758 continue;
759 }
760
761 /* inherit @child and its children */
762 /* TODO: update hname of inherited children */
763 /* list refcount transferred to @new */
764 p = aa_deref_parent(child);
765 rcu_assign_pointer(child->parent, aa_get_profile(new));
766 list_add_rcu(&child->base.list, &new->base.profiles);
767 aa_put_profile(p);
768 }
769 }
770
771 if (!rcu_access_pointer(new->parent)) {
772 struct aa_profile *parent = aa_deref_parent(old);
773 rcu_assign_pointer(new->parent, aa_get_profile(parent));
774 }
775 aa_label_replace(&old->label, &new->label);
776 /* migrate dents must come after label replacement b/c update */
777 __aafs_profile_migrate_dents(old, new);
778
779 if (list_empty(&new->base.list)) {
780 /* new is not on a list already */
781 list_replace_rcu(&old->base.list, &new->base.list);
782 aa_get_profile(new);
783 aa_put_profile(old);
784 } else
785 __list_remove_profile(old);
786}
787
788/**
789 * __lookup_replace - lookup replacement information for a profile
790 * @ns - namespace the lookup occurs in
791 * @hname - name of profile to lookup
792 * @noreplace - true if not replacing an existing profile
793 * @p - Returns: profile to be replaced
794 * @info - Returns: info string on why lookup failed
795 *
796 * Returns: profile to replace (no ref) on success else ptr error
797 */
798static int __lookup_replace(struct aa_ns *ns, const char *hname,
799 bool noreplace, struct aa_profile **p,
800 const char **info)
801{
802 *p = aa_get_profile(__lookup_profile(&ns->base, hname));
803 if (*p) {
804 int error = replacement_allowed(*p, noreplace, info);
805 if (error) {
806 *info = "profile can not be replaced";
807 return error;
808 }
809 }
810
811 return 0;
812}
813
814static void share_name(struct aa_profile *old, struct aa_profile *new)
815{
816 aa_put_str(new->base.hname);
817 aa_get_str(old->base.hname);
818 new->base.hname = old->base.hname;
819 new->base.name = old->base.name;
820 new->label.hname = old->label.hname;
821}
822
823/* Update to newest version of parent after previous replacements
824 * Returns: unrefcount newest version of parent
825 */
826static struct aa_profile *update_to_newest_parent(struct aa_profile *new)
827{
828 struct aa_profile *parent, *newest;
829
830 parent = rcu_dereference_protected(new->parent,
831 mutex_is_locked(&new->ns->lock));
832 newest = aa_get_newest_profile(parent);
833
834 /* parent replaced in this atomic set? */
835 if (newest != parent) {
836 aa_put_profile(parent);
837 rcu_assign_pointer(new->parent, newest);
838 } else
839 aa_put_profile(newest);
840
841 return newest;
842}
843
844/**
845 * aa_replace_profiles - replace profile(s) on the profile list
846 * @policy_ns: namespace load is occurring on
847 * @label: label that is attempting to load/replace policy
848 * @mask: permission mask
849 * @udata: serialized data stream (NOT NULL)
850 *
851 * unpack and replace a profile on the profile list and uses of that profile
852 * by any task creds via invalidating the old version of the profile, which
853 * tasks will notice to update their own cred. If the profile does not exist
854 * on the profile list it is added.
855 *
856 * Returns: size of data consumed else error code on failure.
857 */
858ssize_t aa_replace_profiles(struct aa_ns *policy_ns, struct aa_label *label,
859 u32 mask, struct aa_loaddata *udata)
860{
861 const char *ns_name, *info = NULL;
862 struct aa_ns *ns = NULL;
863 struct aa_load_ent *ent, *tmp;
864 struct aa_loaddata *rawdata_ent;
865 const char *op;
866 ssize_t count, error;
867 LIST_HEAD(lh);
868
869 op = mask & AA_MAY_REPLACE_POLICY ? OP_PROF_REPL : OP_PROF_LOAD;
870 aa_get_loaddata(udata);
871 /* released below */
872 error = aa_unpack(udata, &lh, &ns_name);
873 if (error)
874 goto out;
875
876 /* ensure that profiles are all for the same ns
877 * TODO: update locking to remove this constaint. All profiles in
878 * the load set must succeed as a set or the load will
879 * fail. Sort ent list and take ns locks in hierarchy order
880 */
881 count = 0;
882 list_for_each_entry(ent, &lh, list) {
883 if (ns_name) {
884 if (ent->ns_name &&
885 strcmp(ent->ns_name, ns_name) != 0) {
886 info = "policy load has mixed namespaces";
887 error = -EACCES;
888 goto fail;
889 }
890 } else if (ent->ns_name) {
891 if (count) {
892 info = "policy load has mixed namespaces";
893 error = -EACCES;
894 goto fail;
895 }
896 ns_name = ent->ns_name;
897 } else
898 count++;
899 }
900 if (ns_name) {
901 ns = aa_prepare_ns(policy_ns ? policy_ns : labels_ns(label),
902 ns_name);
903 if (IS_ERR(ns)) {
904 op = OP_PROF_LOAD;
905 info = "failed to prepare namespace";
906 error = PTR_ERR(ns);
907 ns = NULL;
908 ent = NULL;
909 goto fail;
910 }
911 } else
912 ns = aa_get_ns(policy_ns ? policy_ns : labels_ns(label));
913
914 mutex_lock_nested(&ns->lock, ns->level);
915 /* check for duplicate rawdata blobs: space and file dedup */
916 list_for_each_entry(rawdata_ent, &ns->rawdata_list, list) {
917 if (aa_rawdata_eq(rawdata_ent, udata)) {
918 struct aa_loaddata *tmp;
919
920 tmp = __aa_get_loaddata(rawdata_ent);
921 /* check we didn't fail the race */
922 if (tmp) {
923 aa_put_loaddata(udata);
924 udata = tmp;
925 break;
926 }
927 }
928 }
929 /* setup parent and ns info */
930 list_for_each_entry(ent, &lh, list) {
931 struct aa_policy *policy;
932
933 ent->new->rawdata = aa_get_loaddata(udata);
934 error = __lookup_replace(ns, ent->new->base.hname,
935 !(mask & AA_MAY_REPLACE_POLICY),
936 &ent->old, &info);
937 if (error)
938 goto fail_lock;
939
940 if (ent->new->rename) {
941 error = __lookup_replace(ns, ent->new->rename,
942 !(mask & AA_MAY_REPLACE_POLICY),
943 &ent->rename, &info);
944 if (error)
945 goto fail_lock;
946 }
947
948 /* released when @new is freed */
949 ent->new->ns = aa_get_ns(ns);
950
951 if (ent->old || ent->rename)
952 continue;
953
954 /* no ref on policy only use inside lock */
955 policy = __lookup_parent(ns, ent->new->base.hname);
956 if (!policy) {
957 struct aa_profile *p;
958 p = __list_lookup_parent(&lh, ent->new);
959 if (!p) {
960 error = -ENOENT;
961 info = "parent does not exist";
962 goto fail_lock;
963 }
964 rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
965 } else if (policy != &ns->base) {
966 /* released on profile replacement or free_profile */
967 struct aa_profile *p = (struct aa_profile *) policy;
968 rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
969 }
970 }
971
972 /* create new fs entries for introspection if needed */
973 if (!udata->dents[AAFS_LOADDATA_DIR]) {
974 error = __aa_fs_create_rawdata(ns, udata);
975 if (error) {
976 info = "failed to create raw_data dir and files";
977 ent = NULL;
978 goto fail_lock;
979 }
980 }
981 list_for_each_entry(ent, &lh, list) {
982 if (!ent->old) {
983 struct dentry *parent;
984 if (rcu_access_pointer(ent->new->parent)) {
985 struct aa_profile *p;
986 p = aa_deref_parent(ent->new);
987 parent = prof_child_dir(p);
988 } else
989 parent = ns_subprofs_dir(ent->new->ns);
990 error = __aafs_profile_mkdir(ent->new, parent);
991 }
992
993 if (error) {
994 info = "failed to create";
995 goto fail_lock;
996 }
997 }
998
999 /* Done with checks that may fail - do actual replacement */
1000 __aa_bump_ns_revision(ns);
1001 __aa_loaddata_update(udata, ns->revision);
1002 list_for_each_entry_safe(ent, tmp, &lh, list) {
1003 list_del_init(&ent->list);
1004 op = (!ent->old && !ent->rename) ? OP_PROF_LOAD : OP_PROF_REPL;
1005
1006 if (ent->old && ent->old->rawdata == ent->new->rawdata) {
1007 /* dedup actual profile replacement */
1008 audit_policy(label, op, ns_name, ent->new->base.hname,
1009 "same as current profile, skipping",
1010 error);
1011 goto skip;
1012 }
1013
1014 /*
1015 * TODO: finer dedup based on profile range in data. Load set
1016 * can differ but profile may remain unchanged
1017 */
1018 audit_policy(label, op, ns_name, ent->new->base.hname, NULL,
1019 error);
1020
1021 if (ent->old) {
1022 share_name(ent->old, ent->new);
1023 __replace_profile(ent->old, ent->new);
1024 } else {
1025 struct list_head *lh;
1026
1027 if (rcu_access_pointer(ent->new->parent)) {
1028 struct aa_profile *parent;
1029
1030 parent = update_to_newest_parent(ent->new);
1031 lh = &parent->base.profiles;
1032 } else
1033 lh = &ns->base.profiles;
1034 __add_profile(lh, ent->new);
1035 }
1036 skip:
1037 aa_load_ent_free(ent);
1038 }
1039 __aa_labelset_update_subtree(ns);
1040 mutex_unlock(&ns->lock);
1041
1042out:
1043 aa_put_ns(ns);
1044 aa_put_loaddata(udata);
1045
1046 if (error)
1047 return error;
1048 return udata->size;
1049
1050fail_lock:
1051 mutex_unlock(&ns->lock);
1052
1053 /* audit cause of failure */
1054 op = (ent && !ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
1055fail:
1056 audit_policy(label, op, ns_name, ent ? ent->new->base.hname : NULL,
1057 info, error);
1058 /* audit status that rest of profiles in the atomic set failed too */
1059 info = "valid profile in failed atomic policy load";
1060 list_for_each_entry(tmp, &lh, list) {
1061 if (tmp == ent) {
1062 info = "unchecked profile in failed atomic policy load";
1063 /* skip entry that caused failure */
1064 continue;
1065 }
1066 op = (!tmp->old) ? OP_PROF_LOAD : OP_PROF_REPL;
1067 audit_policy(label, op, ns_name, tmp->new->base.hname, info,
1068 error);
1069 }
1070 list_for_each_entry_safe(ent, tmp, &lh, list) {
1071 list_del_init(&ent->list);
1072 aa_load_ent_free(ent);
1073 }
1074
1075 goto out;
1076}
1077
1078/**
1079 * aa_remove_profiles - remove profile(s) from the system
1080 * @policy_ns: namespace the remove is being done from
1081 * @subj: label attempting to remove policy
1082 * @fqname: name of the profile or namespace to remove (NOT NULL)
1083 * @size: size of the name
1084 *
1085 * Remove a profile or sub namespace from the current namespace, so that
1086 * they can not be found anymore and mark them as replaced by unconfined
1087 *
1088 * NOTE: removing confinement does not restore rlimits to preconfinemnet values
1089 *
1090 * Returns: size of data consume else error code if fails
1091 */
1092ssize_t aa_remove_profiles(struct aa_ns *policy_ns, struct aa_label *subj,
1093 char *fqname, size_t size)
1094{
1095 struct aa_ns *ns = NULL;
1096 struct aa_profile *profile = NULL;
1097 const char *name = fqname, *info = NULL;
1098 const char *ns_name = NULL;
1099 ssize_t error = 0;
1100
1101 if (*fqname == 0) {
1102 info = "no profile specified";
1103 error = -ENOENT;
1104 goto fail;
1105 }
1106
1107 if (fqname[0] == ':') {
1108 size_t ns_len;
1109
1110 name = aa_splitn_fqname(fqname, size, &ns_name, &ns_len);
1111 /* released below */
1112 ns = aa_lookupn_ns(policy_ns ? policy_ns : labels_ns(subj),
1113 ns_name, ns_len);
1114 if (!ns) {
1115 info = "namespace does not exist";
1116 error = -ENOENT;
1117 goto fail;
1118 }
1119 } else
1120 /* released below */
1121 ns = aa_get_ns(policy_ns ? policy_ns : labels_ns(subj));
1122
1123 if (!name) {
1124 /* remove namespace - can only happen if fqname[0] == ':' */
1125 mutex_lock_nested(&ns->parent->lock, ns->level);
1126 __aa_remove_ns(ns);
1127 __aa_bump_ns_revision(ns);
1128 mutex_unlock(&ns->parent->lock);
1129 } else {
1130 /* remove profile */
1131 mutex_lock_nested(&ns->lock, ns->level);
1132 profile = aa_get_profile(__lookup_profile(&ns->base, name));
1133 if (!profile) {
1134 error = -ENOENT;
1135 info = "profile does not exist";
1136 goto fail_ns_lock;
1137 }
1138 name = profile->base.hname;
1139 __remove_profile(profile);
1140 __aa_labelset_update_subtree(ns);
1141 __aa_bump_ns_revision(ns);
1142 mutex_unlock(&ns->lock);
1143 }
1144
1145 /* don't fail removal if audit fails */
1146 (void) audit_policy(subj, OP_PROF_RM, ns_name, name, info,
1147 error);
1148 aa_put_ns(ns);
1149 aa_put_profile(profile);
1150 return size;
1151
1152fail_ns_lock:
1153 mutex_unlock(&ns->lock);
1154 aa_put_ns(ns);
1155
1156fail:
1157 (void) audit_policy(subj, OP_PROF_RM, ns_name, name, info,
1158 error);
1159 return error;
1160}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor policy manipulation functions
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 *
10 * AppArmor policy is based around profiles, which contain the rules a
11 * task is confined by. Every task in the system has a profile attached
12 * to it determined either by matching "unconfined" tasks against the
13 * visible set of profiles or by following a profiles attachment rules.
14 *
15 * Each profile exists in a profile namespace which is a container of
16 * visible profiles. Each namespace contains a special "unconfined" profile,
17 * which doesn't enforce any confinement on a task beyond DAC.
18 *
19 * Namespace and profile names can be written together in either
20 * of two syntaxes.
21 * :namespace:profile - used by kernel interfaces for easy detection
22 * namespace://profile - used by policy
23 *
24 * Profile names can not start with : or @ or ^ and may not contain \0
25 *
26 * Reserved profile names
27 * unconfined - special automatically generated unconfined profile
28 * inherit - special name to indicate profile inheritance
29 * null-XXXX-YYYY - special automatically generated learning profiles
30 *
31 * Namespace names may not start with / or @ and may not contain \0 or :
32 * Reserved namespace names
33 * user-XXXX - user defined profiles
34 *
35 * a // in a profile or namespace name indicates a hierarchical name with the
36 * name before the // being the parent and the name after the child.
37 *
38 * Profile and namespace hierarchies serve two different but similar purposes.
39 * The namespace contains the set of visible profiles that are considered
40 * for attachment. The hierarchy of namespaces allows for virtualizing
41 * the namespace so that for example a chroot can have its own set of profiles
42 * which may define some local user namespaces.
43 * The profile hierarchy severs two distinct purposes,
44 * - it allows for sub profiles or hats, which allows an application to run
45 * subprograms under its own profile with different restriction than it
46 * self, and not have it use the system profile.
47 * eg. if a mail program starts an editor, the policy might make the
48 * restrictions tighter on the editor tighter than the mail program,
49 * and definitely different than general editor restrictions
50 * - it allows for binary hierarchy of profiles, so that execution history
51 * is preserved. This feature isn't exploited by AppArmor reference policy
52 * but is allowed. NOTE: this is currently suboptimal because profile
53 * aliasing is not currently implemented so that a profile for each
54 * level must be defined.
55 * eg. /bin/bash///bin/ls as a name would indicate /bin/ls was started
56 * from /bin/bash
57 *
58 * A profile or namespace name that can contain one or more // separators
59 * is referred to as an hname (hierarchical).
60 * eg. /bin/bash//bin/ls
61 *
62 * An fqname is a name that may contain both namespace and profile hnames.
63 * eg. :ns:/bin/bash//bin/ls
64 *
65 * NOTES:
66 * - locking of profile lists is currently fairly coarse. All profile
67 * lists within a namespace use the namespace lock.
68 * FIXME: move profile lists to using rcu_lists
69 */
70
71#include <linux/slab.h>
72#include <linux/spinlock.h>
73#include <linux/string.h>
74#include <linux/cred.h>
75#include <linux/rculist.h>
76#include <linux/user_namespace.h>
77
78#include "include/apparmor.h"
79#include "include/capability.h"
80#include "include/cred.h"
81#include "include/file.h"
82#include "include/ipc.h"
83#include "include/match.h"
84#include "include/path.h"
85#include "include/policy.h"
86#include "include/policy_ns.h"
87#include "include/policy_unpack.h"
88#include "include/resource.h"
89
90int unprivileged_userns_apparmor_policy = 1;
91
92const char *const aa_profile_mode_names[] = {
93 "enforce",
94 "complain",
95 "kill",
96 "unconfined",
97 "user",
98};
99
100
101/**
102 * __add_profile - add a profiles to list and label tree
103 * @list: list to add it to (NOT NULL)
104 * @profile: the profile to add (NOT NULL)
105 *
106 * refcount @profile, should be put by __list_remove_profile
107 *
108 * Requires: namespace lock be held, or list not be shared
109 */
110static void __add_profile(struct list_head *list, struct aa_profile *profile)
111{
112 struct aa_label *l;
113
114 AA_BUG(!list);
115 AA_BUG(!profile);
116 AA_BUG(!profile->ns);
117 AA_BUG(!mutex_is_locked(&profile->ns->lock));
118
119 list_add_rcu(&profile->base.list, list);
120 /* get list reference */
121 aa_get_profile(profile);
122 l = aa_label_insert(&profile->ns->labels, &profile->label);
123 AA_BUG(l != &profile->label);
124 aa_put_label(l);
125}
126
127/**
128 * __list_remove_profile - remove a profile from the list it is on
129 * @profile: the profile to remove (NOT NULL)
130 *
131 * remove a profile from the list, warning generally removal should
132 * be done with __replace_profile as most profile removals are
133 * replacements to the unconfined profile.
134 *
135 * put @profile list refcount
136 *
137 * Requires: namespace lock be held, or list not have been live
138 */
139static void __list_remove_profile(struct aa_profile *profile)
140{
141 AA_BUG(!profile);
142 AA_BUG(!profile->ns);
143 AA_BUG(!mutex_is_locked(&profile->ns->lock));
144
145 list_del_rcu(&profile->base.list);
146 aa_put_profile(profile);
147}
148
149/**
150 * __remove_profile - remove old profile, and children
151 * @profile: profile to be replaced (NOT NULL)
152 *
153 * Requires: namespace list lock be held, or list not be shared
154 */
155static void __remove_profile(struct aa_profile *profile)
156{
157 AA_BUG(!profile);
158 AA_BUG(!profile->ns);
159 AA_BUG(!mutex_is_locked(&profile->ns->lock));
160
161 /* release any children lists first */
162 __aa_profile_list_release(&profile->base.profiles);
163 /* released by free_profile */
164 aa_label_remove(&profile->label);
165 __aafs_profile_rmdir(profile);
166 __list_remove_profile(profile);
167}
168
169/**
170 * __aa_profile_list_release - remove all profiles on the list and put refs
171 * @head: list of profiles (NOT NULL)
172 *
173 * Requires: namespace lock be held
174 */
175void __aa_profile_list_release(struct list_head *head)
176{
177 struct aa_profile *profile, *tmp;
178 list_for_each_entry_safe(profile, tmp, head, base.list)
179 __remove_profile(profile);
180}
181
182/**
183 * aa_free_data - free a data blob
184 * @ptr: data to free
185 * @arg: unused
186 */
187static void aa_free_data(void *ptr, void *arg)
188{
189 struct aa_data *data = ptr;
190
191 kfree_sensitive(data->data);
192 kfree_sensitive(data->key);
193 kfree_sensitive(data);
194}
195
196static void free_attachment(struct aa_attachment *attach)
197{
198 int i;
199
200 for (i = 0; i < attach->xattr_count; i++)
201 kfree_sensitive(attach->xattrs[i]);
202 kfree_sensitive(attach->xattrs);
203 aa_destroy_policydb(&attach->xmatch);
204}
205
206static void free_ruleset(struct aa_ruleset *rules)
207{
208 int i;
209
210 aa_destroy_policydb(&rules->file);
211 aa_destroy_policydb(&rules->policy);
212 aa_free_cap_rules(&rules->caps);
213 aa_free_rlimit_rules(&rules->rlimits);
214
215 for (i = 0; i < rules->secmark_count; i++)
216 kfree_sensitive(rules->secmark[i].label);
217 kfree_sensitive(rules->secmark);
218 kfree_sensitive(rules);
219}
220
221struct aa_ruleset *aa_alloc_ruleset(gfp_t gfp)
222{
223 struct aa_ruleset *rules;
224
225 rules = kzalloc(sizeof(*rules), gfp);
226 if (rules)
227 INIT_LIST_HEAD(&rules->list);
228
229 return rules;
230}
231
232/**
233 * aa_free_profile - free a profile
234 * @profile: the profile to free (MAYBE NULL)
235 *
236 * Free a profile, its hats and null_profile. All references to the profile,
237 * its hats and null_profile must have been put.
238 *
239 * If the profile was referenced from a task context, free_profile() will
240 * be called from an rcu callback routine, so we must not sleep here.
241 */
242void aa_free_profile(struct aa_profile *profile)
243{
244 struct aa_ruleset *rule, *tmp;
245 struct rhashtable *rht;
246
247 AA_DEBUG("%s(%p)\n", __func__, profile);
248
249 if (!profile)
250 return;
251
252 /* free children profiles */
253 aa_policy_destroy(&profile->base);
254 aa_put_profile(rcu_access_pointer(profile->parent));
255
256 aa_put_ns(profile->ns);
257 kfree_sensitive(profile->rename);
258
259 free_attachment(&profile->attach);
260
261 /*
262 * at this point there are no tasks that can have a reference
263 * to rules
264 */
265 list_for_each_entry_safe(rule, tmp, &profile->rules, list) {
266 list_del_init(&rule->list);
267 free_ruleset(rule);
268 }
269 kfree_sensitive(profile->dirname);
270
271 if (profile->data) {
272 rht = profile->data;
273 profile->data = NULL;
274 rhashtable_free_and_destroy(rht, aa_free_data, NULL);
275 kfree_sensitive(rht);
276 }
277
278 kfree_sensitive(profile->hash);
279 aa_put_loaddata(profile->rawdata);
280 aa_label_destroy(&profile->label);
281
282 kfree_sensitive(profile);
283}
284
285/**
286 * aa_alloc_profile - allocate, initialize and return a new profile
287 * @hname: name of the profile (NOT NULL)
288 * @gfp: allocation type
289 *
290 * Returns: refcount profile or NULL on failure
291 */
292struct aa_profile *aa_alloc_profile(const char *hname, struct aa_proxy *proxy,
293 gfp_t gfp)
294{
295 struct aa_profile *profile;
296 struct aa_ruleset *rules;
297
298 /* freed by free_profile - usually through aa_put_profile */
299 profile = kzalloc(struct_size(profile, label.vec, 2), gfp);
300 if (!profile)
301 return NULL;
302
303 if (!aa_policy_init(&profile->base, NULL, hname, gfp))
304 goto fail;
305 if (!aa_label_init(&profile->label, 1, gfp))
306 goto fail;
307
308 INIT_LIST_HEAD(&profile->rules);
309
310 /* allocate the first ruleset, but leave it empty */
311 rules = aa_alloc_ruleset(gfp);
312 if (!rules)
313 goto fail;
314 list_add(&rules->list, &profile->rules);
315
316 /* update being set needed by fs interface */
317 if (!proxy) {
318 proxy = aa_alloc_proxy(&profile->label, gfp);
319 if (!proxy)
320 goto fail;
321 } else
322 aa_get_proxy(proxy);
323 profile->label.proxy = proxy;
324
325 profile->label.hname = profile->base.hname;
326 profile->label.flags |= FLAG_PROFILE;
327 profile->label.vec[0] = profile;
328
329 /* refcount released by caller */
330 return profile;
331
332fail:
333 aa_free_profile(profile);
334
335 return NULL;
336}
337
338/* TODO: profile accounting - setup in remove */
339
340/**
341 * __strn_find_child - find a profile on @head list using substring of @name
342 * @head: list to search (NOT NULL)
343 * @name: name of profile (NOT NULL)
344 * @len: length of @name substring to match
345 *
346 * Requires: rcu_read_lock be held
347 *
348 * Returns: unrefcounted profile ptr, or NULL if not found
349 */
350static struct aa_profile *__strn_find_child(struct list_head *head,
351 const char *name, int len)
352{
353 return (struct aa_profile *)__policy_strn_find(head, name, len);
354}
355
356/**
357 * __find_child - find a profile on @head list with a name matching @name
358 * @head: list to search (NOT NULL)
359 * @name: name of profile (NOT NULL)
360 *
361 * Requires: rcu_read_lock be held
362 *
363 * Returns: unrefcounted profile ptr, or NULL if not found
364 */
365static struct aa_profile *__find_child(struct list_head *head, const char *name)
366{
367 return __strn_find_child(head, name, strlen(name));
368}
369
370/**
371 * aa_find_child - find a profile by @name in @parent
372 * @parent: profile to search (NOT NULL)
373 * @name: profile name to search for (NOT NULL)
374 *
375 * Returns: a refcounted profile or NULL if not found
376 */
377struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name)
378{
379 struct aa_profile *profile;
380
381 rcu_read_lock();
382 do {
383 profile = __find_child(&parent->base.profiles, name);
384 } while (profile && !aa_get_profile_not0(profile));
385 rcu_read_unlock();
386
387 /* refcount released by caller */
388 return profile;
389}
390
391/**
392 * __lookup_parent - lookup the parent of a profile of name @hname
393 * @ns: namespace to lookup profile in (NOT NULL)
394 * @hname: hierarchical profile name to find parent of (NOT NULL)
395 *
396 * Lookups up the parent of a fully qualified profile name, the profile
397 * that matches hname does not need to exist, in general this
398 * is used to load a new profile.
399 *
400 * Requires: rcu_read_lock be held
401 *
402 * Returns: unrefcounted policy or NULL if not found
403 */
404static struct aa_policy *__lookup_parent(struct aa_ns *ns,
405 const char *hname)
406{
407 struct aa_policy *policy;
408 struct aa_profile *profile = NULL;
409 char *split;
410
411 policy = &ns->base;
412
413 for (split = strstr(hname, "//"); split;) {
414 profile = __strn_find_child(&policy->profiles, hname,
415 split - hname);
416 if (!profile)
417 return NULL;
418 policy = &profile->base;
419 hname = split + 2;
420 split = strstr(hname, "//");
421 }
422 if (!profile)
423 return &ns->base;
424 return &profile->base;
425}
426
427/**
428 * __create_missing_ancestors - create place holders for missing ancestores
429 * @ns: namespace to lookup profile in (NOT NULL)
430 * @hname: hierarchical profile name to find parent of (NOT NULL)
431 * @gfp: type of allocation.
432 *
433 * Returns: NULL on error, parent profile on success
434 *
435 * Requires: ns mutex lock held
436 *
437 * Returns: unrefcounted parent policy or NULL if error creating
438 * place holder profiles.
439 */
440static struct aa_policy *__create_missing_ancestors(struct aa_ns *ns,
441 const char *hname,
442 gfp_t gfp)
443{
444 struct aa_policy *policy;
445 struct aa_profile *parent, *profile = NULL;
446 char *split;
447
448 AA_BUG(!ns);
449 AA_BUG(!hname);
450
451 policy = &ns->base;
452
453 for (split = strstr(hname, "//"); split;) {
454 parent = profile;
455 profile = __strn_find_child(&policy->profiles, hname,
456 split - hname);
457 if (!profile) {
458 const char *name = kstrndup(hname, split - hname,
459 gfp);
460 if (!name)
461 return NULL;
462 profile = aa_alloc_null(parent, name, gfp);
463 kfree(name);
464 if (!profile)
465 return NULL;
466 if (!parent)
467 profile->ns = aa_get_ns(ns);
468 }
469 policy = &profile->base;
470 hname = split + 2;
471 split = strstr(hname, "//");
472 }
473 if (!profile)
474 return &ns->base;
475 return &profile->base;
476}
477
478/**
479 * __lookupn_profile - lookup the profile matching @hname
480 * @base: base list to start looking up profile name from (NOT NULL)
481 * @hname: hierarchical profile name (NOT NULL)
482 * @n: length of @hname
483 *
484 * Requires: rcu_read_lock be held
485 *
486 * Returns: unrefcounted profile pointer or NULL if not found
487 *
488 * Do a relative name lookup, recursing through profile tree.
489 */
490static struct aa_profile *__lookupn_profile(struct aa_policy *base,
491 const char *hname, size_t n)
492{
493 struct aa_profile *profile = NULL;
494 const char *split;
495
496 for (split = strnstr(hname, "//", n); split;
497 split = strnstr(hname, "//", n)) {
498 profile = __strn_find_child(&base->profiles, hname,
499 split - hname);
500 if (!profile)
501 return NULL;
502
503 base = &profile->base;
504 n -= split + 2 - hname;
505 hname = split + 2;
506 }
507
508 if (n)
509 return __strn_find_child(&base->profiles, hname, n);
510 return NULL;
511}
512
513static struct aa_profile *__lookup_profile(struct aa_policy *base,
514 const char *hname)
515{
516 return __lookupn_profile(base, hname, strlen(hname));
517}
518
519/**
520 * aa_lookupn_profile - find a profile by its full or partial name
521 * @ns: the namespace to start from (NOT NULL)
522 * @hname: name to do lookup on. Does not contain namespace prefix (NOT NULL)
523 * @n: size of @hname
524 *
525 * Returns: refcounted profile or NULL if not found
526 */
527struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
528 size_t n)
529{
530 struct aa_profile *profile;
531
532 rcu_read_lock();
533 do {
534 profile = __lookupn_profile(&ns->base, hname, n);
535 } while (profile && !aa_get_profile_not0(profile));
536 rcu_read_unlock();
537
538 /* the unconfined profile is not in the regular profile list */
539 if (!profile && strncmp(hname, "unconfined", n) == 0)
540 profile = aa_get_newest_profile(ns->unconfined);
541
542 /* refcount released by caller */
543 return profile;
544}
545
546struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *hname)
547{
548 return aa_lookupn_profile(ns, hname, strlen(hname));
549}
550
551struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
552 const char *fqname, size_t n)
553{
554 struct aa_profile *profile;
555 struct aa_ns *ns;
556 const char *name, *ns_name;
557 size_t ns_len;
558
559 name = aa_splitn_fqname(fqname, n, &ns_name, &ns_len);
560 if (ns_name) {
561 ns = aa_lookupn_ns(labels_ns(base), ns_name, ns_len);
562 if (!ns)
563 return NULL;
564 } else
565 ns = aa_get_ns(labels_ns(base));
566
567 if (name)
568 profile = aa_lookupn_profile(ns, name, n - (name - fqname));
569 else if (ns)
570 /* default profile for ns, currently unconfined */
571 profile = aa_get_newest_profile(ns->unconfined);
572 else
573 profile = NULL;
574 aa_put_ns(ns);
575
576 return profile;
577}
578
579
580struct aa_profile *aa_alloc_null(struct aa_profile *parent, const char *name,
581 gfp_t gfp)
582{
583 struct aa_profile *profile;
584 struct aa_ruleset *rules;
585
586 profile = aa_alloc_profile(name, NULL, gfp);
587 if (!profile)
588 return NULL;
589
590 /* TODO: ideally we should inherit abi from parent */
591 profile->label.flags |= FLAG_NULL;
592 rules = list_first_entry(&profile->rules, typeof(*rules), list);
593 rules->file.dfa = aa_get_dfa(nulldfa);
594 rules->policy.dfa = aa_get_dfa(nulldfa);
595
596 if (parent) {
597 profile->path_flags = parent->path_flags;
598
599 /* released on free_profile */
600 rcu_assign_pointer(profile->parent, aa_get_profile(parent));
601 profile->ns = aa_get_ns(parent->ns);
602 }
603
604 return profile;
605}
606
607/**
608 * aa_new_learning_profile - create or find a null-X learning profile
609 * @parent: profile that caused this profile to be created (NOT NULL)
610 * @hat: true if the null- learning profile is a hat
611 * @base: name to base the null profile off of
612 * @gfp: type of allocation
613 *
614 * Find/Create a null- complain mode profile used in learning mode. The
615 * name of the profile is unique and follows the format of parent//null-XXX.
616 * where XXX is based on the @name or if that fails or is not supplied
617 * a unique number
618 *
619 * null profiles are added to the profile list but the list does not
620 * hold a count on them so that they are automatically released when
621 * not in use.
622 *
623 * Returns: new refcounted profile else NULL on failure
624 */
625struct aa_profile *aa_new_learning_profile(struct aa_profile *parent, bool hat,
626 const char *base, gfp_t gfp)
627{
628 struct aa_profile *p, *profile;
629 const char *bname;
630 char *name = NULL;
631
632 AA_BUG(!parent);
633
634 if (base) {
635 name = kmalloc(strlen(parent->base.hname) + 8 + strlen(base),
636 gfp);
637 if (name) {
638 sprintf(name, "%s//null-%s", parent->base.hname, base);
639 goto name;
640 }
641 /* fall through to try shorter uniq */
642 }
643
644 name = kmalloc(strlen(parent->base.hname) + 2 + 7 + 8, gfp);
645 if (!name)
646 return NULL;
647 sprintf(name, "%s//null-%x", parent->base.hname,
648 atomic_inc_return(&parent->ns->uniq_null));
649
650name:
651 /* lookup to see if this is a dup creation */
652 bname = basename(name);
653 profile = aa_find_child(parent, bname);
654 if (profile)
655 goto out;
656
657 profile = aa_alloc_null(parent, name, gfp);
658 if (!profile)
659 goto fail;
660 profile->mode = APPARMOR_COMPLAIN;
661 if (hat)
662 profile->label.flags |= FLAG_HAT;
663
664 mutex_lock_nested(&profile->ns->lock, profile->ns->level);
665 p = __find_child(&parent->base.profiles, bname);
666 if (p) {
667 aa_free_profile(profile);
668 profile = aa_get_profile(p);
669 } else {
670 __add_profile(&parent->base.profiles, profile);
671 }
672 mutex_unlock(&profile->ns->lock);
673
674 /* refcount released by caller */
675out:
676 kfree(name);
677
678 return profile;
679
680fail:
681 kfree(name);
682 aa_free_profile(profile);
683 return NULL;
684}
685
686/**
687 * replacement_allowed - test to see if replacement is allowed
688 * @profile: profile to test if it can be replaced (MAYBE NULL)
689 * @noreplace: true if replacement shouldn't be allowed but addition is okay
690 * @info: Returns - info about why replacement failed (NOT NULL)
691 *
692 * Returns: %0 if replacement allowed else error code
693 */
694static int replacement_allowed(struct aa_profile *profile, int noreplace,
695 const char **info)
696{
697 if (profile) {
698 if (profile->label.flags & FLAG_IMMUTIBLE) {
699 *info = "cannot replace immutable profile";
700 return -EPERM;
701 } else if (noreplace) {
702 *info = "profile already exists";
703 return -EEXIST;
704 }
705 }
706 return 0;
707}
708
709/* audit callback for net specific fields */
710static void audit_cb(struct audit_buffer *ab, void *va)
711{
712 struct common_audit_data *sa = va;
713
714 if (aad(sa)->iface.ns) {
715 audit_log_format(ab, " ns=");
716 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
717 }
718}
719
720/**
721 * audit_policy - Do auditing of policy changes
722 * @label: label to check if it can manage policy
723 * @op: policy operation being performed
724 * @ns_name: name of namespace being manipulated
725 * @name: name of profile being manipulated (NOT NULL)
726 * @info: any extra information to be audited (MAYBE NULL)
727 * @error: error code
728 *
729 * Returns: the error to be returned after audit is done
730 */
731static int audit_policy(struct aa_label *label, const char *op,
732 const char *ns_name, const char *name,
733 const char *info, int error)
734{
735 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE, op);
736
737 aad(&sa)->iface.ns = ns_name;
738 aad(&sa)->name = name;
739 aad(&sa)->info = info;
740 aad(&sa)->error = error;
741 aad(&sa)->label = label;
742
743 aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, audit_cb);
744
745 return error;
746}
747
748/* don't call out to other LSMs in the stack for apparmor policy admin
749 * permissions
750 */
751static int policy_ns_capable(struct aa_label *label,
752 struct user_namespace *userns, int cap)
753{
754 int err;
755
756 /* check for MAC_ADMIN cap in cred */
757 err = cap_capable(current_cred(), userns, cap, CAP_OPT_NONE);
758 if (!err)
759 err = aa_capable(label, cap, CAP_OPT_NONE);
760
761 return err;
762}
763
764/**
765 * aa_policy_view_capable - check if viewing policy in at @ns is allowed
766 * label: label that is trying to view policy in ns
767 * ns: namespace being viewed by @label (may be NULL if @label's ns)
768 * Returns: true if viewing policy is allowed
769 *
770 * If @ns is NULL then the namespace being viewed is assumed to be the
771 * tasks current namespace.
772 */
773bool aa_policy_view_capable(struct aa_label *label, struct aa_ns *ns)
774{
775 struct user_namespace *user_ns = current_user_ns();
776 struct aa_ns *view_ns = labels_view(label);
777 bool root_in_user_ns = uid_eq(current_euid(), make_kuid(user_ns, 0)) ||
778 in_egroup_p(make_kgid(user_ns, 0));
779 bool response = false;
780 if (!ns)
781 ns = view_ns;
782
783 if (root_in_user_ns && aa_ns_visible(view_ns, ns, true) &&
784 (user_ns == &init_user_ns ||
785 (unprivileged_userns_apparmor_policy != 0 &&
786 user_ns->level == view_ns->level)))
787 response = true;
788
789 return response;
790}
791
792bool aa_policy_admin_capable(struct aa_label *label, struct aa_ns *ns)
793{
794 struct user_namespace *user_ns = current_user_ns();
795 bool capable = policy_ns_capable(label, user_ns, CAP_MAC_ADMIN) == 0;
796
797 AA_DEBUG("cap_mac_admin? %d\n", capable);
798 AA_DEBUG("policy locked? %d\n", aa_g_lock_policy);
799
800 return aa_policy_view_capable(label, ns) && capable &&
801 !aa_g_lock_policy;
802}
803
804bool aa_current_policy_view_capable(struct aa_ns *ns)
805{
806 struct aa_label *label;
807 bool res;
808
809 label = __begin_current_label_crit_section();
810 res = aa_policy_view_capable(label, ns);
811 __end_current_label_crit_section(label);
812
813 return res;
814}
815
816bool aa_current_policy_admin_capable(struct aa_ns *ns)
817{
818 struct aa_label *label;
819 bool res;
820
821 label = __begin_current_label_crit_section();
822 res = aa_policy_admin_capable(label, ns);
823 __end_current_label_crit_section(label);
824
825 return res;
826}
827
828/**
829 * aa_may_manage_policy - can the current task manage policy
830 * @label: label to check if it can manage policy
831 * @op: the policy manipulation operation being done
832 *
833 * Returns: 0 if the task is allowed to manipulate policy else error
834 */
835int aa_may_manage_policy(struct aa_label *label, struct aa_ns *ns, u32 mask)
836{
837 const char *op;
838
839 if (mask & AA_MAY_REMOVE_POLICY)
840 op = OP_PROF_RM;
841 else if (mask & AA_MAY_REPLACE_POLICY)
842 op = OP_PROF_REPL;
843 else
844 op = OP_PROF_LOAD;
845
846 /* check if loading policy is locked out */
847 if (aa_g_lock_policy)
848 return audit_policy(label, op, NULL, NULL, "policy_locked",
849 -EACCES);
850
851 if (!aa_policy_admin_capable(label, ns))
852 return audit_policy(label, op, NULL, NULL, "not policy admin",
853 -EACCES);
854
855 /* TODO: add fine grained mediation of policy loads */
856 return 0;
857}
858
859static struct aa_profile *__list_lookup_parent(struct list_head *lh,
860 struct aa_profile *profile)
861{
862 const char *base = basename(profile->base.hname);
863 long len = base - profile->base.hname;
864 struct aa_load_ent *ent;
865
866 /* parent won't have trailing // so remove from len */
867 if (len <= 2)
868 return NULL;
869 len -= 2;
870
871 list_for_each_entry(ent, lh, list) {
872 if (ent->new == profile)
873 continue;
874 if (strncmp(ent->new->base.hname, profile->base.hname, len) ==
875 0 && ent->new->base.hname[len] == 0)
876 return ent->new;
877 }
878
879 return NULL;
880}
881
882/**
883 * __replace_profile - replace @old with @new on a list
884 * @old: profile to be replaced (NOT NULL)
885 * @new: profile to replace @old with (NOT NULL)
886 * @share_proxy: transfer @old->proxy to @new
887 *
888 * Will duplicate and refcount elements that @new inherits from @old
889 * and will inherit @old children.
890 *
891 * refcount @new for list, put @old list refcount
892 *
893 * Requires: namespace list lock be held, or list not be shared
894 */
895static void __replace_profile(struct aa_profile *old, struct aa_profile *new)
896{
897 struct aa_profile *child, *tmp;
898
899 if (!list_empty(&old->base.profiles)) {
900 LIST_HEAD(lh);
901 list_splice_init_rcu(&old->base.profiles, &lh, synchronize_rcu);
902
903 list_for_each_entry_safe(child, tmp, &lh, base.list) {
904 struct aa_profile *p;
905
906 list_del_init(&child->base.list);
907 p = __find_child(&new->base.profiles, child->base.name);
908 if (p) {
909 /* @p replaces @child */
910 __replace_profile(child, p);
911 continue;
912 }
913
914 /* inherit @child and its children */
915 /* TODO: update hname of inherited children */
916 /* list refcount transferred to @new */
917 p = aa_deref_parent(child);
918 rcu_assign_pointer(child->parent, aa_get_profile(new));
919 list_add_rcu(&child->base.list, &new->base.profiles);
920 aa_put_profile(p);
921 }
922 }
923
924 if (!rcu_access_pointer(new->parent)) {
925 struct aa_profile *parent = aa_deref_parent(old);
926 rcu_assign_pointer(new->parent, aa_get_profile(parent));
927 }
928 aa_label_replace(&old->label, &new->label);
929 /* migrate dents must come after label replacement b/c update */
930 __aafs_profile_migrate_dents(old, new);
931
932 if (list_empty(&new->base.list)) {
933 /* new is not on a list already */
934 list_replace_rcu(&old->base.list, &new->base.list);
935 aa_get_profile(new);
936 aa_put_profile(old);
937 } else
938 __list_remove_profile(old);
939}
940
941/**
942 * __lookup_replace - lookup replacement information for a profile
943 * @ns - namespace the lookup occurs in
944 * @hname - name of profile to lookup
945 * @noreplace - true if not replacing an existing profile
946 * @p - Returns: profile to be replaced
947 * @info - Returns: info string on why lookup failed
948 *
949 * Returns: profile to replace (no ref) on success else ptr error
950 */
951static int __lookup_replace(struct aa_ns *ns, const char *hname,
952 bool noreplace, struct aa_profile **p,
953 const char **info)
954{
955 *p = aa_get_profile(__lookup_profile(&ns->base, hname));
956 if (*p) {
957 int error = replacement_allowed(*p, noreplace, info);
958 if (error) {
959 *info = "profile can not be replaced";
960 return error;
961 }
962 }
963
964 return 0;
965}
966
967static void share_name(struct aa_profile *old, struct aa_profile *new)
968{
969 aa_put_str(new->base.hname);
970 aa_get_str(old->base.hname);
971 new->base.hname = old->base.hname;
972 new->base.name = old->base.name;
973 new->label.hname = old->label.hname;
974}
975
976/* Update to newest version of parent after previous replacements
977 * Returns: unrefcount newest version of parent
978 */
979static struct aa_profile *update_to_newest_parent(struct aa_profile *new)
980{
981 struct aa_profile *parent, *newest;
982
983 parent = rcu_dereference_protected(new->parent,
984 mutex_is_locked(&new->ns->lock));
985 newest = aa_get_newest_profile(parent);
986
987 /* parent replaced in this atomic set? */
988 if (newest != parent) {
989 aa_put_profile(parent);
990 rcu_assign_pointer(new->parent, newest);
991 } else
992 aa_put_profile(newest);
993
994 return newest;
995}
996
997/**
998 * aa_replace_profiles - replace profile(s) on the profile list
999 * @policy_ns: namespace load is occurring on
1000 * @label: label that is attempting to load/replace policy
1001 * @mask: permission mask
1002 * @udata: serialized data stream (NOT NULL)
1003 *
1004 * unpack and replace a profile on the profile list and uses of that profile
1005 * by any task creds via invalidating the old version of the profile, which
1006 * tasks will notice to update their own cred. If the profile does not exist
1007 * on the profile list it is added.
1008 *
1009 * Returns: size of data consumed else error code on failure.
1010 */
1011ssize_t aa_replace_profiles(struct aa_ns *policy_ns, struct aa_label *label,
1012 u32 mask, struct aa_loaddata *udata)
1013{
1014 const char *ns_name = NULL, *info = NULL;
1015 struct aa_ns *ns = NULL;
1016 struct aa_load_ent *ent, *tmp;
1017 struct aa_loaddata *rawdata_ent;
1018 const char *op;
1019 ssize_t count, error;
1020 LIST_HEAD(lh);
1021
1022 op = mask & AA_MAY_REPLACE_POLICY ? OP_PROF_REPL : OP_PROF_LOAD;
1023 aa_get_loaddata(udata);
1024 /* released below */
1025 error = aa_unpack(udata, &lh, &ns_name);
1026 if (error)
1027 goto out;
1028
1029 /* ensure that profiles are all for the same ns
1030 * TODO: update locking to remove this constaint. All profiles in
1031 * the load set must succeed as a set or the load will
1032 * fail. Sort ent list and take ns locks in hierarchy order
1033 */
1034 count = 0;
1035 list_for_each_entry(ent, &lh, list) {
1036 if (ns_name) {
1037 if (ent->ns_name &&
1038 strcmp(ent->ns_name, ns_name) != 0) {
1039 info = "policy load has mixed namespaces";
1040 error = -EACCES;
1041 goto fail;
1042 }
1043 } else if (ent->ns_name) {
1044 if (count) {
1045 info = "policy load has mixed namespaces";
1046 error = -EACCES;
1047 goto fail;
1048 }
1049 ns_name = ent->ns_name;
1050 } else
1051 count++;
1052 }
1053 if (ns_name) {
1054 ns = aa_prepare_ns(policy_ns ? policy_ns : labels_ns(label),
1055 ns_name);
1056 if (IS_ERR(ns)) {
1057 op = OP_PROF_LOAD;
1058 info = "failed to prepare namespace";
1059 error = PTR_ERR(ns);
1060 ns = NULL;
1061 ent = NULL;
1062 goto fail;
1063 }
1064 } else
1065 ns = aa_get_ns(policy_ns ? policy_ns : labels_ns(label));
1066
1067 mutex_lock_nested(&ns->lock, ns->level);
1068 /* check for duplicate rawdata blobs: space and file dedup */
1069 if (!list_empty(&ns->rawdata_list)) {
1070 list_for_each_entry(rawdata_ent, &ns->rawdata_list, list) {
1071 if (aa_rawdata_eq(rawdata_ent, udata)) {
1072 struct aa_loaddata *tmp;
1073
1074 tmp = __aa_get_loaddata(rawdata_ent);
1075 /* check we didn't fail the race */
1076 if (tmp) {
1077 aa_put_loaddata(udata);
1078 udata = tmp;
1079 break;
1080 }
1081 }
1082 }
1083 }
1084 /* setup parent and ns info */
1085 list_for_each_entry(ent, &lh, list) {
1086 struct aa_policy *policy;
1087 struct aa_profile *p;
1088
1089 if (aa_g_export_binary)
1090 ent->new->rawdata = aa_get_loaddata(udata);
1091 error = __lookup_replace(ns, ent->new->base.hname,
1092 !(mask & AA_MAY_REPLACE_POLICY),
1093 &ent->old, &info);
1094 if (error)
1095 goto fail_lock;
1096
1097 if (ent->new->rename) {
1098 error = __lookup_replace(ns, ent->new->rename,
1099 !(mask & AA_MAY_REPLACE_POLICY),
1100 &ent->rename, &info);
1101 if (error)
1102 goto fail_lock;
1103 }
1104
1105 /* released when @new is freed */
1106 ent->new->ns = aa_get_ns(ns);
1107
1108 if (ent->old || ent->rename)
1109 continue;
1110
1111 /* no ref on policy only use inside lock */
1112 p = NULL;
1113 policy = __lookup_parent(ns, ent->new->base.hname);
1114 if (!policy) {
1115 /* first check for parent in the load set */
1116 p = __list_lookup_parent(&lh, ent->new);
1117 if (!p) {
1118 /*
1119 * fill in missing parent with null
1120 * profile that doesn't have
1121 * permissions. This allows for
1122 * individual profile loading where
1123 * the child is loaded before the
1124 * parent, and outside of the current
1125 * atomic set. This unfortunately can
1126 * happen with some userspaces. The
1127 * null profile will be replaced once
1128 * the parent is loaded.
1129 */
1130 policy = __create_missing_ancestors(ns,
1131 ent->new->base.hname,
1132 GFP_KERNEL);
1133 if (!policy) {
1134 error = -ENOENT;
1135 info = "parent does not exist";
1136 goto fail_lock;
1137 }
1138 }
1139 }
1140 if (!p && policy != &ns->base)
1141 /* released on profile replacement or free_profile */
1142 p = (struct aa_profile *) policy;
1143 rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
1144 }
1145
1146 /* create new fs entries for introspection if needed */
1147 if (!udata->dents[AAFS_LOADDATA_DIR] && aa_g_export_binary) {
1148 error = __aa_fs_create_rawdata(ns, udata);
1149 if (error) {
1150 info = "failed to create raw_data dir and files";
1151 ent = NULL;
1152 goto fail_lock;
1153 }
1154 }
1155 list_for_each_entry(ent, &lh, list) {
1156 if (!ent->old) {
1157 struct dentry *parent;
1158 if (rcu_access_pointer(ent->new->parent)) {
1159 struct aa_profile *p;
1160 p = aa_deref_parent(ent->new);
1161 parent = prof_child_dir(p);
1162 } else
1163 parent = ns_subprofs_dir(ent->new->ns);
1164 error = __aafs_profile_mkdir(ent->new, parent);
1165 }
1166
1167 if (error) {
1168 info = "failed to create";
1169 goto fail_lock;
1170 }
1171 }
1172
1173 /* Done with checks that may fail - do actual replacement */
1174 __aa_bump_ns_revision(ns);
1175 if (aa_g_export_binary)
1176 __aa_loaddata_update(udata, ns->revision);
1177 list_for_each_entry_safe(ent, tmp, &lh, list) {
1178 list_del_init(&ent->list);
1179 op = (!ent->old && !ent->rename) ? OP_PROF_LOAD : OP_PROF_REPL;
1180
1181 if (ent->old && ent->old->rawdata == ent->new->rawdata &&
1182 ent->new->rawdata) {
1183 /* dedup actual profile replacement */
1184 audit_policy(label, op, ns_name, ent->new->base.hname,
1185 "same as current profile, skipping",
1186 error);
1187 /* break refcount cycle with proxy. */
1188 aa_put_proxy(ent->new->label.proxy);
1189 ent->new->label.proxy = NULL;
1190 goto skip;
1191 }
1192
1193 /*
1194 * TODO: finer dedup based on profile range in data. Load set
1195 * can differ but profile may remain unchanged
1196 */
1197 audit_policy(label, op, ns_name, ent->new->base.hname, NULL,
1198 error);
1199
1200 if (ent->old) {
1201 share_name(ent->old, ent->new);
1202 __replace_profile(ent->old, ent->new);
1203 } else {
1204 struct list_head *lh;
1205
1206 if (rcu_access_pointer(ent->new->parent)) {
1207 struct aa_profile *parent;
1208
1209 parent = update_to_newest_parent(ent->new);
1210 lh = &parent->base.profiles;
1211 } else
1212 lh = &ns->base.profiles;
1213 __add_profile(lh, ent->new);
1214 }
1215 skip:
1216 aa_load_ent_free(ent);
1217 }
1218 __aa_labelset_update_subtree(ns);
1219 mutex_unlock(&ns->lock);
1220
1221out:
1222 aa_put_ns(ns);
1223 aa_put_loaddata(udata);
1224 kfree(ns_name);
1225
1226 if (error)
1227 return error;
1228 return udata->size;
1229
1230fail_lock:
1231 mutex_unlock(&ns->lock);
1232
1233 /* audit cause of failure */
1234 op = (ent && !ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
1235fail:
1236 audit_policy(label, op, ns_name, ent ? ent->new->base.hname : NULL,
1237 info, error);
1238 /* audit status that rest of profiles in the atomic set failed too */
1239 info = "valid profile in failed atomic policy load";
1240 list_for_each_entry(tmp, &lh, list) {
1241 if (tmp == ent) {
1242 info = "unchecked profile in failed atomic policy load";
1243 /* skip entry that caused failure */
1244 continue;
1245 }
1246 op = (!tmp->old) ? OP_PROF_LOAD : OP_PROF_REPL;
1247 audit_policy(label, op, ns_name, tmp->new->base.hname, info,
1248 error);
1249 }
1250 list_for_each_entry_safe(ent, tmp, &lh, list) {
1251 list_del_init(&ent->list);
1252 aa_load_ent_free(ent);
1253 }
1254
1255 goto out;
1256}
1257
1258/**
1259 * aa_remove_profiles - remove profile(s) from the system
1260 * @policy_ns: namespace the remove is being done from
1261 * @subj: label attempting to remove policy
1262 * @fqname: name of the profile or namespace to remove (NOT NULL)
1263 * @size: size of the name
1264 *
1265 * Remove a profile or sub namespace from the current namespace, so that
1266 * they can not be found anymore and mark them as replaced by unconfined
1267 *
1268 * NOTE: removing confinement does not restore rlimits to preconfinement values
1269 *
1270 * Returns: size of data consume else error code if fails
1271 */
1272ssize_t aa_remove_profiles(struct aa_ns *policy_ns, struct aa_label *subj,
1273 char *fqname, size_t size)
1274{
1275 struct aa_ns *ns = NULL;
1276 struct aa_profile *profile = NULL;
1277 const char *name = fqname, *info = NULL;
1278 const char *ns_name = NULL;
1279 ssize_t error = 0;
1280
1281 if (*fqname == 0) {
1282 info = "no profile specified";
1283 error = -ENOENT;
1284 goto fail;
1285 }
1286
1287 if (fqname[0] == ':') {
1288 size_t ns_len;
1289
1290 name = aa_splitn_fqname(fqname, size, &ns_name, &ns_len);
1291 /* released below */
1292 ns = aa_lookupn_ns(policy_ns ? policy_ns : labels_ns(subj),
1293 ns_name, ns_len);
1294 if (!ns) {
1295 info = "namespace does not exist";
1296 error = -ENOENT;
1297 goto fail;
1298 }
1299 } else
1300 /* released below */
1301 ns = aa_get_ns(policy_ns ? policy_ns : labels_ns(subj));
1302
1303 if (!name) {
1304 /* remove namespace - can only happen if fqname[0] == ':' */
1305 mutex_lock_nested(&ns->parent->lock, ns->parent->level);
1306 __aa_bump_ns_revision(ns);
1307 __aa_remove_ns(ns);
1308 mutex_unlock(&ns->parent->lock);
1309 } else {
1310 /* remove profile */
1311 mutex_lock_nested(&ns->lock, ns->level);
1312 profile = aa_get_profile(__lookup_profile(&ns->base, name));
1313 if (!profile) {
1314 error = -ENOENT;
1315 info = "profile does not exist";
1316 goto fail_ns_lock;
1317 }
1318 name = profile->base.hname;
1319 __aa_bump_ns_revision(ns);
1320 __remove_profile(profile);
1321 __aa_labelset_update_subtree(ns);
1322 mutex_unlock(&ns->lock);
1323 }
1324
1325 /* don't fail removal if audit fails */
1326 (void) audit_policy(subj, OP_PROF_RM, ns_name, name, info,
1327 error);
1328 aa_put_ns(ns);
1329 aa_put_profile(profile);
1330 return size;
1331
1332fail_ns_lock:
1333 mutex_unlock(&ns->lock);
1334 aa_put_ns(ns);
1335
1336fail:
1337 (void) audit_policy(subj, OP_PROF_RM, ns_name, name, info,
1338 error);
1339 return error;
1340}