1 // SPDX-License-Identifier: GPL-2.0-only
3 * AppArmor security module
5 * This file contains AppArmor label definitions
7 * Copyright 2017 Canonical Ltd.
10 #include <linux/audit.h>
11 #include <linux/seq_file.h>
12 #include <linux/sort.h>
14 #include "include/apparmor.h"
15 #include "include/cred.h"
16 #include "include/label.h"
17 #include "include/policy.h"
18 #include "include/secid.h"
22 * the aa_label represents the set of profiles confining an object
24 * Labels maintain a reference count to the set of pointers they reference
25 * Labels are ref counted by
26 * tasks and object via the security field/security context off the field
27 * code - will take a ref count on a label if it needs the label
28 * beyond what is possible with an rcu_read_lock.
29 * profiles - each profile is a label
30 * secids - a pinned secid will keep a refcount of the label it is
32 * objects - inode, files, sockets, ...
34 * Labels are not ref counted by the label set, so they maybe removed and
35 * freed when no longer in use.
39 #define PROXY_POISON 97
40 #define LABEL_POISON 100
42 static void free_proxy(struct aa_proxy *proxy)
45 /* p->label will not updated any more as p is dead */
46 aa_put_label(rcu_dereference_protected(proxy->label, true));
47 memset(proxy, 0, sizeof(*proxy));
48 RCU_INIT_POINTER(proxy->label, (struct aa_label *)PROXY_POISON);
53 void aa_proxy_kref(struct kref *kref)
55 struct aa_proxy *proxy = container_of(kref, struct aa_proxy, count);
60 struct aa_proxy *aa_alloc_proxy(struct aa_label *label, gfp_t gfp)
64 new = kzalloc(sizeof(struct aa_proxy), gfp);
66 kref_init(&new->count);
67 rcu_assign_pointer(new->label, aa_get_label(label));
72 /* requires profile list write lock held */
73 void __aa_proxy_redirect(struct aa_label *orig, struct aa_label *new)
79 lockdep_assert_held_write(&labels_set(orig)->lock);
81 tmp = rcu_dereference_protected(orig->proxy->label,
82 &labels_ns(orig)->lock);
83 rcu_assign_pointer(orig->proxy->label, aa_get_label(new));
84 orig->flags |= FLAG_STALE;
88 static void __proxy_share(struct aa_label *old, struct aa_label *new)
90 struct aa_proxy *proxy = new->proxy;
92 new->proxy = aa_get_proxy(old->proxy);
93 __aa_proxy_redirect(old, new);
99 * ns_cmp - compare ns for label set ordering
100 * @a: ns to compare (NOT NULL)
101 * @b: ns to compare (NOT NULL)
103 * Returns: <0 if a < b
107 static int ns_cmp(struct aa_ns *a, struct aa_ns *b)
113 AA_BUG(!a->base.hname);
114 AA_BUG(!b->base.hname);
119 res = a->level - b->level;
123 return strcmp(a->base.hname, b->base.hname);
127 * profile_cmp - profile comparison for set ordering
128 * @a: profile to compare (NOT NULL)
129 * @b: profile to compare (NOT NULL)
131 * Returns: <0 if a < b
135 static int profile_cmp(struct aa_profile *a, struct aa_profile *b)
143 AA_BUG(!a->base.hname);
144 AA_BUG(!b->base.hname);
146 if (a == b || a->base.hname == b->base.hname)
148 res = ns_cmp(a->ns, b->ns);
152 return strcmp(a->base.hname, b->base.hname);
156 * vec_cmp - label comparison for set ordering
157 * @a: label to compare (NOT NULL)
158 * @vec: vector of profiles to compare (NOT NULL)
161 * Returns: <0 if a < vec
165 static int vec_cmp(struct aa_profile **a, int an, struct aa_profile **b, int bn)
176 for (i = 0; i < an && i < bn; i++) {
177 int res = profile_cmp(a[i], b[i]);
186 static bool vec_is_stale(struct aa_profile **vec, int n)
192 for (i = 0; i < n; i++) {
193 if (profile_is_stale(vec[i]))
200 static long accum_vec_flags(struct aa_profile **vec, int n)
202 long u = FLAG_UNCONFINED;
207 for (i = 0; i < n; i++) {
208 u |= vec[i]->label.flags & (FLAG_DEBUG1 | FLAG_DEBUG2 |
210 if (!(u & vec[i]->label.flags & FLAG_UNCONFINED))
211 u &= ~FLAG_UNCONFINED;
217 static int sort_cmp(const void *a, const void *b)
219 return profile_cmp(*(struct aa_profile **)a, *(struct aa_profile **)b);
223 * assumes vec is sorted
224 * Assumes @vec has null terminator at vec[n], and will null terminate
227 static inline int unique(struct aa_profile **vec, int n)
229 int i, pos, dups = 0;
235 for (i = 1; i < n; i++) {
236 int res = profile_cmp(vec[pos], vec[i]);
238 AA_BUG(res > 0, "vec not sorted");
241 aa_put_profile(vec[i]);
256 * aa_vec_unique - canonical sort and unique a list of profiles
257 * @n: number of refcounted profiles in the list (@n > 0)
258 * @vec: list of profiles to sort and merge
260 * Returns: the number of duplicates eliminated == references put
262 * If @flags & VEC_FLAG_TERMINATE @vec has null terminator at vec[n], and will
263 * null terminate vec[n - dups]
265 int aa_vec_unique(struct aa_profile **vec, int n, int flags)
272 /* vecs are usually small and inorder, have a fallback for larger */
274 sort(vec, n, sizeof(struct aa_profile *), sort_cmp, NULL);
275 dups = unique(vec, n);
279 /* insertion sort + unique in one */
280 for (i = 1; i < n; i++) {
281 struct aa_profile *tmp = vec[i];
284 for (pos = i - 1 - dups; pos >= 0; pos--) {
285 int res = profile_cmp(vec[pos], tmp);
288 /* drop duplicate entry */
295 /* pos is at entry < tmp, or index -1. Set to insert pos */
298 for (j = i - dups; j > pos; j--)
308 if (flags & VEC_FLAG_TERMINATE)
309 vec[n - dups] = NULL;
315 void aa_label_destroy(struct aa_label *label)
319 if (!label_isprofile(label)) {
320 struct aa_profile *profile;
323 aa_put_str(label->hname);
325 label_for_each(i, label, profile) {
326 aa_put_profile(profile);
327 label->vec[i.i] = (struct aa_profile *)
328 (LABEL_POISON + (long) i.i);
333 if (rcu_dereference_protected(label->proxy->label, true) == label)
334 rcu_assign_pointer(label->proxy->label, NULL);
335 aa_put_proxy(label->proxy);
337 aa_free_secid(label->secid);
339 label->proxy = (struct aa_proxy *) PROXY_POISON + 1;
342 void aa_label_free(struct aa_label *label)
347 aa_label_destroy(label);
351 static void label_free_switch(struct aa_label *label)
353 if (label->flags & FLAG_NS_COUNT)
354 aa_free_ns(labels_ns(label));
355 else if (label_isprofile(label))
356 aa_free_profile(labels_profile(label));
358 aa_label_free(label);
361 static void label_free_rcu(struct rcu_head *head)
363 struct aa_label *label = container_of(head, struct aa_label, rcu);
365 if (label->flags & FLAG_IN_TREE)
366 (void) aa_label_remove(label);
367 label_free_switch(label);
370 void aa_label_kref(struct kref *kref)
372 struct aa_label *label = container_of(kref, struct aa_label, count);
373 struct aa_ns *ns = labels_ns(label);
376 /* never live, no rcu callback needed, just using the fn */
377 label_free_switch(label);
380 /* TODO: update labels_profile macro so it works here */
381 AA_BUG(label_isprofile(label) &&
382 on_list_rcu(&label->vec[0]->base.profiles));
383 AA_BUG(label_isprofile(label) &&
384 on_list_rcu(&label->vec[0]->base.list));
386 /* TODO: if compound label and not stale add to reclaim cache */
387 call_rcu(&label->rcu, label_free_rcu);
390 static void label_free_or_put_new(struct aa_label *label, struct aa_label *new)
393 /* need to free directly to break circular ref with proxy */
399 bool aa_label_init(struct aa_label *label, int size, gfp_t gfp)
404 if (aa_alloc_secid(label, gfp) < 0)
407 label->size = size; /* doesn't include null */
408 label->vec[size] = NULL; /* null terminate */
409 kref_init(&label->count);
410 RB_CLEAR_NODE(&label->node);
416 * aa_label_alloc - allocate a label with a profile vector of @size length
417 * @size: size of profile vector in the label
418 * @proxy: proxy to use OR null if to allocate a new one
419 * @gfp: memory allocation type
422 * else NULL if failed
424 struct aa_label *aa_label_alloc(int size, struct aa_proxy *proxy, gfp_t gfp)
426 struct aa_label *new;
430 /* + 1 for null terminator entry on vec */
431 new = kzalloc(struct_size(new, vec, size + 1), gfp);
432 AA_DEBUG("%s (%p)\n", __func__, new);
436 if (!aa_label_init(new, size, gfp))
440 proxy = aa_alloc_proxy(new, gfp);
445 /* just set new's proxy, don't redirect proxy here if it was passed in*/
458 * label_cmp - label comparison for set ordering
459 * @a: label to compare (NOT NULL)
460 * @b: label to compare (NOT NULL)
462 * Returns: <0 if a < b
466 static int label_cmp(struct aa_label *a, struct aa_label *b)
473 return vec_cmp(a->vec, a->size, b->vec, b->size);
476 /* helper fn for label_for_each_confined */
477 int aa_label_next_confined(struct aa_label *label, int i)
482 for (; i < label->size; i++) {
483 if (!profile_unconfined(label->vec[i]))
491 * __aa_label_next_not_in_set - return the next profile of @sub not in @set
493 * @set: label to test against
494 * @sub: label to if is subset of @set
496 * Returns: profile in @sub that is not in @set, with iterator set pos after
497 * else NULL if @sub is a subset of @set
499 struct aa_profile *__aa_label_next_not_in_set(struct label_it *I,
500 struct aa_label *set,
501 struct aa_label *sub)
506 AA_BUG(I->i > set->size);
509 AA_BUG(I->j > sub->size);
511 while (I->j < sub->size && I->i < set->size) {
512 int res = profile_cmp(sub->vec[I->j], set->vec[I->i]);
520 return sub->vec[(I->j)++];
523 if (I->j < sub->size)
524 return sub->vec[(I->j)++];
530 * aa_label_is_subset - test if @sub is a subset of @set
531 * @set: label to test against
532 * @sub: label to test if is subset of @set
534 * Returns: true if @sub is subset of @set
537 bool aa_label_is_subset(struct aa_label *set, struct aa_label *sub)
539 struct label_it i = { };
547 return __aa_label_next_not_in_set(&i, set, sub) == NULL;
551 * aa_label_is_unconfined_subset - test if @sub is a subset of @set
552 * @set: label to test against
553 * @sub: label to test if is subset of @set
555 * This checks for subset but taking into account unconfined. IF
556 * @sub contains an unconfined profile that does not have a matching
557 * unconfined in @set then this will not cause the test to fail.
558 * Conversely we don't care about an unconfined in @set that is not in
561 * Returns: true if @sub is special_subset of @set
564 bool aa_label_is_unconfined_subset(struct aa_label *set, struct aa_label *sub)
566 struct label_it i = { };
567 struct aa_profile *p;
576 p = __aa_label_next_not_in_set(&i, set, sub);
577 if (p && !profile_unconfined(p))
586 * __label_remove - remove @label from the label set
587 * @l: label to remove
588 * @new: label to redirect to
590 * Requires: labels_set(@label)->lock write_lock
591 * Returns: true if the label was in the tree and removed
593 static bool __label_remove(struct aa_label *label, struct aa_label *new)
595 struct aa_labelset *ls = labels_set(label);
599 lockdep_assert_held_write(&ls->lock);
602 __aa_proxy_redirect(label, new);
604 if (!label_is_stale(label))
605 __label_make_stale(label);
607 if (label->flags & FLAG_IN_TREE) {
608 rb_erase(&label->node, &ls->root);
609 label->flags &= ~FLAG_IN_TREE;
617 * __label_replace - replace @old with @new in label set
618 * @old: label to remove from label set
619 * @new: label to replace @old with
621 * Requires: labels_set(@old)->lock write_lock
622 * valid ref count be held on @new
623 * Returns: true if @old was in set and replaced by @new
625 * Note: current implementation requires label set be order in such a way
626 * that @new directly replaces @old position in the set (ie.
627 * using pointer comparison of the label address would not work)
629 static bool __label_replace(struct aa_label *old, struct aa_label *new)
631 struct aa_labelset *ls = labels_set(old);
636 lockdep_assert_held_write(&ls->lock);
637 AA_BUG(new->flags & FLAG_IN_TREE);
639 if (!label_is_stale(old))
640 __label_make_stale(old);
642 if (old->flags & FLAG_IN_TREE) {
643 rb_replace_node(&old->node, &new->node, &ls->root);
644 old->flags &= ~FLAG_IN_TREE;
645 new->flags |= FLAG_IN_TREE;
653 * __label_insert - attempt to insert @l into a label set
654 * @ls: set of labels to insert @l into (NOT NULL)
655 * @label: new label to insert (NOT NULL)
656 * @replace: whether insertion should replace existing entry that is not stale
658 * Requires: @ls->lock
659 * caller to hold a valid ref on l
660 * if @replace is true l has a preallocated proxy associated
661 * Returns: @l if successful in inserting @l - with additional refcount
662 * else ref counted equivalent label that is already in the set,
663 * the else condition only happens if @replace is false
665 static struct aa_label *__label_insert(struct aa_labelset *ls,
666 struct aa_label *label, bool replace)
668 struct rb_node **new, *parent = NULL;
672 AA_BUG(labels_set(label) != ls);
673 lockdep_assert_held_write(&ls->lock);
674 AA_BUG(label->flags & FLAG_IN_TREE);
676 /* Figure out where to put new node */
677 new = &ls->root.rb_node;
679 struct aa_label *this = rb_entry(*new, struct aa_label, node);
680 int result = label_cmp(label, this);
684 /* !__aa_get_label means queued for destruction,
685 * so replace in place, however the label has
686 * died before the replacement so do not share
689 if (!replace && !label_is_stale(this)) {
690 if (__aa_get_label(this))
693 __proxy_share(this, label);
694 AA_BUG(!__label_replace(this, label));
695 return aa_get_label(label);
696 } else if (result < 0)
697 new = &((*new)->rb_left);
698 else /* (result > 0) */
699 new = &((*new)->rb_right);
702 /* Add new node and rebalance tree. */
703 rb_link_node(&label->node, parent, new);
704 rb_insert_color(&label->node, &ls->root);
705 label->flags |= FLAG_IN_TREE;
707 return aa_get_label(label);
711 * __vec_find - find label that matches @vec in label set
712 * @vec: vec of profiles to find matching label for (NOT NULL)
715 * Requires: @vec_labelset(vec) lock held
716 * caller to hold a valid ref on l
718 * Returns: ref counted @label if matching label is in tree
719 * ref counted label that is equiv to @l in tree
720 * else NULL if @vec equiv is not in tree
722 static struct aa_label *__vec_find(struct aa_profile **vec, int n)
724 struct rb_node *node;
730 node = vec_labelset(vec, n)->root.rb_node;
732 struct aa_label *this = rb_entry(node, struct aa_label, node);
733 int result = vec_cmp(this->vec, this->size, vec, n);
736 node = node->rb_left;
738 node = node->rb_right;
740 return __aa_get_label(this);
747 * __label_find - find label @label in label set
748 * @label: label to find (NOT NULL)
750 * Requires: labels_set(@label)->lock held
751 * caller to hold a valid ref on l
753 * Returns: ref counted @label if @label is in tree OR
754 * ref counted label that is equiv to @label in tree
755 * else NULL if @label or equiv is not in tree
757 static struct aa_label *__label_find(struct aa_label *label)
761 return __vec_find(label->vec, label->size);
766 * aa_label_remove - remove a label from the labelset
767 * @label: label to remove
769 * Returns: true if @label was removed from the tree
770 * else @label was not in tree so it could not be removed
772 bool aa_label_remove(struct aa_label *label)
774 struct aa_labelset *ls = labels_set(label);
780 write_lock_irqsave(&ls->lock, flags);
781 res = __label_remove(label, ns_unconfined(labels_ns(label)));
782 write_unlock_irqrestore(&ls->lock, flags);
788 * aa_label_replace - replace a label @old with a new version @new
789 * @old: label to replace
790 * @new: label replacing @old
792 * Returns: true if @old was in tree and replaced
793 * else @old was not in tree, and @new was not inserted
795 bool aa_label_replace(struct aa_label *old, struct aa_label *new)
800 if (name_is_shared(old, new) && labels_ns(old) == labels_ns(new)) {
801 write_lock_irqsave(&labels_set(old)->lock, flags);
802 if (old->proxy != new->proxy)
803 __proxy_share(old, new);
805 __aa_proxy_redirect(old, new);
806 res = __label_replace(old, new);
807 write_unlock_irqrestore(&labels_set(old)->lock, flags);
810 struct aa_labelset *ls = labels_set(old);
812 write_lock_irqsave(&ls->lock, flags);
813 res = __label_remove(old, new);
814 if (labels_ns(old) != labels_ns(new)) {
815 write_unlock_irqrestore(&ls->lock, flags);
816 ls = labels_set(new);
817 write_lock_irqsave(&ls->lock, flags);
819 l = __label_insert(ls, new, true);
821 write_unlock_irqrestore(&ls->lock, flags);
829 * vec_find - find label @l in label set
830 * @vec: array of profiles to find equiv label for (NOT NULL)
833 * Returns: refcounted label if @vec equiv is in tree
834 * else NULL if @vec equiv is not in tree
836 static struct aa_label *vec_find(struct aa_profile **vec, int n)
838 struct aa_labelset *ls;
839 struct aa_label *label;
846 ls = vec_labelset(vec, n);
847 read_lock_irqsave(&ls->lock, flags);
848 label = __vec_find(vec, n);
849 read_unlock_irqrestore(&ls->lock, flags);
854 /* requires sort and merge done first */
855 static struct aa_label *vec_create_and_insert_label(struct aa_profile **vec,
858 struct aa_label *label = NULL;
859 struct aa_labelset *ls;
861 struct aa_label *new;
867 return aa_get_label(&vec[0]->label);
869 ls = labels_set(&vec[len - 1]->label);
871 /* TODO: enable when read side is lockless
872 * check if label exists before taking locks
874 new = aa_label_alloc(len, NULL, gfp);
878 for (i = 0; i < len; i++)
879 new->vec[i] = aa_get_profile(vec[i]);
881 write_lock_irqsave(&ls->lock, flags);
882 label = __label_insert(ls, new, false);
883 write_unlock_irqrestore(&ls->lock, flags);
884 label_free_or_put_new(label, new);
889 struct aa_label *aa_vec_find_or_create_label(struct aa_profile **vec, int len,
892 struct aa_label *label = vec_find(vec, len);
897 return vec_create_and_insert_label(vec, len, gfp);
901 * aa_label_find - find label @label in label set
902 * @label: label to find (NOT NULL)
904 * Requires: caller to hold a valid ref on l
906 * Returns: refcounted @label if @label is in tree
907 * refcounted label that is equiv to @label in tree
908 * else NULL if @label or equiv is not in tree
910 struct aa_label *aa_label_find(struct aa_label *label)
914 return vec_find(label->vec, label->size);
919 * aa_label_insert - insert label @label into @ls or return existing label
920 * @ls - labelset to insert @label into
921 * @label - label to insert
923 * Requires: caller to hold a valid ref on @label
925 * Returns: ref counted @label if successful in inserting @label
926 * else ref counted equivalent label that is already in the set
928 struct aa_label *aa_label_insert(struct aa_labelset *ls, struct aa_label *label)
936 /* check if label exists before taking lock */
937 if (!label_is_stale(label)) {
938 read_lock_irqsave(&ls->lock, flags);
939 l = __label_find(label);
940 read_unlock_irqrestore(&ls->lock, flags);
945 write_lock_irqsave(&ls->lock, flags);
946 l = __label_insert(ls, label, false);
947 write_unlock_irqrestore(&ls->lock, flags);
954 * aa_label_next_in_merge - find the next profile when merging @a and @b
959 * Returns: next profile
960 * else null if no more profiles
962 struct aa_profile *aa_label_next_in_merge(struct label_it *I,
970 AA_BUG(I->i > a->size);
972 AA_BUG(I->j > b->size);
974 if (I->i < a->size) {
975 if (I->j < b->size) {
976 int res = profile_cmp(a->vec[I->i], b->vec[I->j]);
979 return b->vec[(I->j)++];
984 return a->vec[(I->i)++];
988 return b->vec[(I->j)++];
994 * label_merge_cmp - cmp of @a merging with @b against @z for set ordering
995 * @a: label to merge then compare (NOT NULL)
996 * @b: label to merge then compare (NOT NULL)
997 * @z: label to compare merge against (NOT NULL)
999 * Assumes: using the most recent versions of @a, @b, and @z
1001 * Returns: <0 if a < b
1005 static int label_merge_cmp(struct aa_label *a, struct aa_label *b,
1008 struct aa_profile *p = NULL;
1009 struct label_it i = { };
1017 k < z->size && (p = aa_label_next_in_merge(&i, a, b));
1019 int res = profile_cmp(p, z->vec[k]);
1027 else if (k < z->size)
1033 * label_merge_insert - create a new label by merging @a and @b
1034 * @new: preallocated label to merge into (NOT NULL)
1035 * @a: label to merge with @b (NOT NULL)
1036 * @b: label to merge with @a (NOT NULL)
1038 * Requires: preallocated proxy
1040 * Returns: ref counted label either @new if merge is unique
1041 * @a if @b is a subset of @a
1042 * @b if @a is a subset of @b
1044 * NOTE: will not use @new if the merge results in @new == @a or @b
1046 * Must be used within labelset write lock to avoid racing with
1047 * setting labels stale.
1049 static struct aa_label *label_merge_insert(struct aa_label *new,
1053 struct aa_label *label;
1054 struct aa_labelset *ls;
1055 struct aa_profile *next;
1057 unsigned long flags;
1058 int k = 0, invcount = 0;
1062 AA_BUG(a->size < 0);
1064 AA_BUG(b->size < 0);
1066 AA_BUG(new->size < a->size + b->size);
1068 label_for_each_in_merge(i, a, b, next) {
1070 if (profile_is_stale(next)) {
1071 new->vec[k] = aa_get_newest_profile(next);
1072 AA_BUG(!new->vec[k]->label.proxy);
1073 AA_BUG(!new->vec[k]->label.proxy->label);
1074 if (next->label.proxy != new->vec[k]->label.proxy)
1079 new->vec[k++] = aa_get_profile(next);
1081 /* set to actual size which is <= allocated len */
1086 new->size -= aa_vec_unique(&new->vec[0], new->size,
1087 VEC_FLAG_TERMINATE);
1088 /* TODO: deal with reference labels */
1089 if (new->size == 1) {
1090 label = aa_get_label(&new->vec[0]->label);
1093 } else if (!stale) {
1095 * merge could be same as a || b, note: it is not possible
1096 * for new->size == a->size == b->size unless a == b
1099 return aa_get_label(a);
1100 else if (k == b->size)
1101 return aa_get_label(b);
1103 new->flags |= accum_vec_flags(new->vec, new->size);
1104 ls = labels_set(new);
1105 write_lock_irqsave(&ls->lock, flags);
1106 label = __label_insert(labels_set(new), new, false);
1107 write_unlock_irqrestore(&ls->lock, flags);
1113 * labelset_of_merge - find which labelset a merged label should be inserted
1114 * @a: label to merge and insert
1115 * @b: label to merge and insert
1117 * Returns: labelset that the merged label should be inserted into
1119 static struct aa_labelset *labelset_of_merge(struct aa_label *a,
1122 struct aa_ns *nsa = labels_ns(a);
1123 struct aa_ns *nsb = labels_ns(b);
1125 if (ns_cmp(nsa, nsb) <= 0)
1126 return &nsa->labels;
1127 return &nsb->labels;
1131 * __label_find_merge - find label that is equiv to merge of @a and @b
1132 * @ls: set of labels to search (NOT NULL)
1133 * @a: label to merge with @b (NOT NULL)
1134 * @b: label to merge with @a (NOT NULL)
1136 * Requires: ls->lock read_lock held
1138 * Returns: ref counted label that is equiv to merge of @a and @b
1139 * else NULL if merge of @a and @b is not in set
1141 static struct aa_label *__label_find_merge(struct aa_labelset *ls,
1145 struct rb_node *node;
1152 return __label_find(a);
1154 node = ls->root.rb_node;
1156 struct aa_label *this = container_of(node, struct aa_label,
1158 int result = label_merge_cmp(a, b, this);
1161 node = node->rb_left;
1162 else if (result > 0)
1163 node = node->rb_right;
1165 return __aa_get_label(this);
1173 * aa_label_find_merge - find label that is equiv to merge of @a and @b
1174 * @a: label to merge with @b (NOT NULL)
1175 * @b: label to merge with @a (NOT NULL)
1177 * Requires: labels be fully constructed with a valid ns
1179 * Returns: ref counted label that is equiv to merge of @a and @b
1180 * else NULL if merge of @a and @b is not in set
1182 struct aa_label *aa_label_find_merge(struct aa_label *a, struct aa_label *b)
1184 struct aa_labelset *ls;
1185 struct aa_label *label, *ar = NULL, *br = NULL;
1186 unsigned long flags;
1191 if (label_is_stale(a))
1192 a = ar = aa_get_newest_label(a);
1193 if (label_is_stale(b))
1194 b = br = aa_get_newest_label(b);
1195 ls = labelset_of_merge(a, b);
1196 read_lock_irqsave(&ls->lock, flags);
1197 label = __label_find_merge(ls, a, b);
1198 read_unlock_irqrestore(&ls->lock, flags);
1206 * aa_label_merge - attempt to insert new merged label of @a and @b
1207 * @ls: set of labels to insert label into (NOT NULL)
1208 * @a: label to merge with @b (NOT NULL)
1209 * @b: label to merge with @a (NOT NULL)
1210 * @gfp: memory allocation type
1212 * Requires: caller to hold valid refs on @a and @b
1213 * labels be fully constructed with a valid ns
1215 * Returns: ref counted new label if successful in inserting merge of a & b
1216 * else ref counted equivalent label that is already in the set.
1217 * else NULL if could not create label (-ENOMEM)
1219 struct aa_label *aa_label_merge(struct aa_label *a, struct aa_label *b,
1222 struct aa_label *label = NULL;
1228 return aa_get_newest_label(a);
1230 /* TODO: enable when read side is lockless
1231 * check if label exists before taking locks
1232 if (!label_is_stale(a) && !label_is_stale(b))
1233 label = aa_label_find_merge(a, b);
1237 struct aa_label *new;
1239 a = aa_get_newest_label(a);
1240 b = aa_get_newest_label(b);
1242 /* could use label_merge_len(a, b), but requires double
1243 * comparison for small savings
1245 new = aa_label_alloc(a->size + b->size, NULL, gfp);
1249 label = label_merge_insert(new, a, b);
1250 label_free_or_put_new(label, new);
1259 /* match a profile and its associated ns component if needed
1260 * Assumes visibility test has already been done.
1261 * If a subns profile is not to be matched should be prescreened with
1264 static inline aa_state_t match_component(struct aa_profile *profile,
1265 struct aa_ruleset *rules,
1266 struct aa_profile *tp,
1269 const char *ns_name;
1271 if (profile->ns == tp->ns)
1272 return aa_dfa_match(rules->policy.dfa, state, tp->base.hname);
1274 /* try matching with namespace name and then profile */
1275 ns_name = aa_ns_name(profile->ns, tp->ns, true);
1276 state = aa_dfa_match_len(rules->policy.dfa, state, ":", 1);
1277 state = aa_dfa_match(rules->policy.dfa, state, ns_name);
1278 state = aa_dfa_match_len(rules->policy.dfa, state, ":", 1);
1279 return aa_dfa_match(rules->policy.dfa, state, tp->base.hname);
1283 * label_compound_match - find perms for full compound label
1284 * @profile: profile to find perms for
1285 * @label: label to check access permissions for
1286 * @start: state to start match in
1287 * @subns: whether to do permission checks on components in a subns
1288 * @request: permissions to request
1289 * @perms: perms struct to set
1291 * Returns: 0 on success else ERROR
1293 * For the label A//&B//&C this does the perm match for A//&B//&C
1294 * @perms should be preinitialized with allperms OR a previous permission
1295 * check to be stacked.
1297 static int label_compound_match(struct aa_profile *profile,
1298 struct aa_ruleset *rules,
1299 struct aa_label *label,
1300 aa_state_t state, bool subns, u32 request,
1301 struct aa_perms *perms)
1303 struct aa_profile *tp;
1306 /* find first subcomponent that is visible */
1307 label_for_each(i, label, tp) {
1308 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1310 state = match_component(profile, rules, tp, state);
1316 /* no component visible */
1321 label_for_each_cont(i, label, tp) {
1322 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1324 state = aa_dfa_match(rules->policy.dfa, state, "//&");
1325 state = match_component(profile, rules, tp, state);
1329 *perms = *aa_lookup_perms(&rules->policy, state);
1330 aa_apply_modes_to_perms(profile, perms);
1331 if ((perms->allow & request) != request)
1342 * label_components_match - find perms for all subcomponents of a label
1343 * @profile: profile to find perms for
1344 * @rules: ruleset to search
1345 * @label: label to check access permissions for
1346 * @start: state to start match in
1347 * @subns: whether to do permission checks on components in a subns
1348 * @request: permissions to request
1349 * @perms: an initialized perms struct to add accumulation to
1351 * Returns: 0 on success else ERROR
1353 * For the label A//&B//&C this does the perm match for each of A and B and C
1354 * @perms should be preinitialized with allperms OR a previous permission
1355 * check to be stacked.
1357 static int label_components_match(struct aa_profile *profile,
1358 struct aa_ruleset *rules,
1359 struct aa_label *label, aa_state_t start,
1360 bool subns, u32 request,
1361 struct aa_perms *perms)
1363 struct aa_profile *tp;
1365 struct aa_perms tmp;
1366 aa_state_t state = 0;
1368 /* find first subcomponent to test */
1369 label_for_each(i, label, tp) {
1370 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1372 state = match_component(profile, rules, tp, start);
1378 /* no subcomponents visible - no change in perms */
1382 tmp = *aa_lookup_perms(&rules->policy, state);
1383 aa_apply_modes_to_perms(profile, &tmp);
1384 aa_perms_accum(perms, &tmp);
1385 label_for_each_cont(i, label, tp) {
1386 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1388 state = match_component(profile, rules, tp, start);
1391 tmp = *aa_lookup_perms(&rules->policy, state);
1392 aa_apply_modes_to_perms(profile, &tmp);
1393 aa_perms_accum(perms, &tmp);
1396 if ((perms->allow & request) != request)
1407 * aa_label_match - do a multi-component label match
1408 * @profile: profile to match against (NOT NULL)
1409 * @rules: ruleset to search
1410 * @label: label to match (NOT NULL)
1411 * @state: state to start in
1412 * @subns: whether to match subns components
1413 * @request: permission request
1414 * @perms: Returns computed perms (NOT NULL)
1416 * Returns: the state the match finished in, may be the none matching state
1418 int aa_label_match(struct aa_profile *profile, struct aa_ruleset *rules,
1419 struct aa_label *label, aa_state_t state, bool subns,
1420 u32 request, struct aa_perms *perms)
1422 int error = label_compound_match(profile, rules, label, state, subns,
1428 return label_components_match(profile, rules, label, state, subns,
1434 * aa_update_label_name - update a label to have a stored name
1435 * @ns: ns being viewed from (NOT NULL)
1436 * @label: label to update (NOT NULL)
1437 * @gfp: type of memory allocation
1439 * Requires: labels_set(label) not locked in caller
1441 * note: only updates the label name if it does not have a name already
1442 * and if it is in the labelset
1444 bool aa_update_label_name(struct aa_ns *ns, struct aa_label *label, gfp_t gfp)
1446 struct aa_labelset *ls;
1447 unsigned long flags;
1448 char __counted *name;
1454 if (label->hname || labels_ns(label) != ns)
1457 if (aa_label_acntsxprint(&name, ns, label, FLAGS_NONE, gfp) < 0)
1460 ls = labels_set(label);
1461 write_lock_irqsave(&ls->lock, flags);
1462 if (!label->hname && label->flags & FLAG_IN_TREE) {
1463 label->hname = name;
1467 write_unlock_irqrestore(&ls->lock, flags);
1473 * cached label name is present and visible
1474 * @label->hname only exists if label is namespace hierachical
1476 static inline bool use_label_hname(struct aa_ns *ns, struct aa_label *label,
1479 if (label->hname && (!ns || labels_ns(label) == ns) &&
1480 !(flags & ~FLAG_SHOW_MODE))
1486 /* helper macro for snprint routines */
1487 #define update_for_len(total, len, size, str) \
1489 size_t ulen = len; \
1493 ulen = min(ulen, size); \
1499 * aa_profile_snxprint - print a profile name to a buffer
1500 * @str: buffer to write to. (MAY BE NULL if @size == 0)
1501 * @size: size of buffer
1502 * @view: namespace profile is being viewed from
1503 * @profile: profile to view (NOT NULL)
1504 * @flags: whether to include the mode string
1505 * @prev_ns: last ns printed when used in compound print
1507 * Returns: size of name written or would be written if larger than
1510 * Note: will not print anything if the profile is not visible
1512 static int aa_profile_snxprint(char *str, size_t size, struct aa_ns *view,
1513 struct aa_profile *profile, int flags,
1514 struct aa_ns **prev_ns)
1516 const char *ns_name = NULL;
1518 AA_BUG(!str && size != 0);
1522 view = profiles_ns(profile);
1524 if (view != profile->ns &&
1525 (!prev_ns || (*prev_ns != profile->ns))) {
1527 *prev_ns = profile->ns;
1528 ns_name = aa_ns_name(view, profile->ns,
1529 flags & FLAG_VIEW_SUBNS);
1530 if (ns_name == aa_hidden_ns_name) {
1531 if (flags & FLAG_HIDDEN_UNCONFINED)
1532 return snprintf(str, size, "%s", "unconfined");
1533 return snprintf(str, size, "%s", ns_name);
1537 if ((flags & FLAG_SHOW_MODE) && profile != profile->ns->unconfined) {
1538 const char *modestr = aa_profile_mode_names[profile->mode];
1541 return snprintf(str, size, ":%s:%s (%s)", ns_name,
1542 profile->base.hname, modestr);
1543 return snprintf(str, size, "%s (%s)", profile->base.hname,
1548 return snprintf(str, size, ":%s:%s", ns_name,
1549 profile->base.hname);
1550 return snprintf(str, size, "%s", profile->base.hname);
1553 static const char *label_modename(struct aa_ns *ns, struct aa_label *label,
1556 struct aa_profile *profile;
1558 int mode = -1, count = 0;
1560 label_for_each(i, label, profile) {
1561 if (aa_ns_visible(ns, profile->ns, flags & FLAG_VIEW_SUBNS)) {
1563 if (profile == profile->ns->unconfined)
1564 /* special case unconfined so stacks with
1565 * unconfined don't report as mixed. ie.
1566 * profile_foo//&:ns1:unconfined (mixed)
1570 mode = profile->mode;
1571 else if (mode != profile->mode)
1579 /* everything was unconfined */
1580 mode = APPARMOR_UNCONFINED;
1582 return aa_profile_mode_names[mode];
1585 /* if any visible label is not unconfined the display_mode returns true */
1586 static inline bool display_mode(struct aa_ns *ns, struct aa_label *label,
1589 if ((flags & FLAG_SHOW_MODE)) {
1590 struct aa_profile *profile;
1593 label_for_each(i, label, profile) {
1594 if (aa_ns_visible(ns, profile->ns,
1595 flags & FLAG_VIEW_SUBNS) &&
1596 profile != profile->ns->unconfined)
1599 /* only ns->unconfined in set of profiles in ns */
1607 * aa_label_snxprint - print a label name to a string buffer
1608 * @str: buffer to write to. (MAY BE NULL if @size == 0)
1609 * @size: size of buffer
1610 * @ns: namespace profile is being viewed from
1611 * @label: label to view (NOT NULL)
1612 * @flags: whether to include the mode string
1614 * Returns: size of name written or would be written if larger than
1617 * Note: labels do not have to be strictly hierarchical to the ns as
1618 * objects may be shared across different namespaces and thus
1619 * pickup labeling from each ns. If a particular part of the
1620 * label is not visible it will just be excluded. And if none
1621 * of the label is visible "---" will be used.
1623 int aa_label_snxprint(char *str, size_t size, struct aa_ns *ns,
1624 struct aa_label *label, int flags)
1626 struct aa_profile *profile;
1627 struct aa_ns *prev_ns = NULL;
1629 int count = 0, total = 0;
1632 AA_BUG(!str && size != 0);
1635 if (AA_DEBUG_LABEL && (flags & FLAG_ABS_ROOT)) {
1637 len = snprintf(str, size, "_");
1638 update_for_len(total, len, size, str);
1640 ns = labels_ns(label);
1643 label_for_each(i, label, profile) {
1644 if (aa_ns_visible(ns, profile->ns, flags & FLAG_VIEW_SUBNS)) {
1646 len = snprintf(str, size, "//&");
1647 update_for_len(total, len, size, str);
1649 len = aa_profile_snxprint(str, size, ns, profile,
1650 flags & FLAG_VIEW_SUBNS,
1652 update_for_len(total, len, size, str);
1658 if (flags & FLAG_HIDDEN_UNCONFINED)
1659 return snprintf(str, size, "%s", "unconfined");
1660 return snprintf(str, size, "%s", aa_hidden_ns_name);
1663 /* count == 1 && ... is for backwards compat where the mode
1664 * is not displayed for 'unconfined' in the current ns
1666 if (display_mode(ns, label, flags)) {
1667 len = snprintf(str, size, " (%s)",
1668 label_modename(ns, label, flags));
1669 update_for_len(total, len, size, str);
1674 #undef update_for_len
1677 * aa_label_asxprint - allocate a string buffer and print label into it
1678 * @strp: Returns - the allocated buffer with the label name. (NOT NULL)
1679 * @ns: namespace profile is being viewed from
1680 * @label: label to view (NOT NULL)
1681 * @flags: flags controlling what label info is printed
1682 * @gfp: kernel memory allocation type
1684 * Returns: size of name written or would be written if larger than
1687 int aa_label_asxprint(char **strp, struct aa_ns *ns, struct aa_label *label,
1688 int flags, gfp_t gfp)
1695 size = aa_label_snxprint(NULL, 0, ns, label, flags);
1699 *strp = kmalloc(size + 1, gfp);
1702 return aa_label_snxprint(*strp, size + 1, ns, label, flags);
1706 * aa_label_acntsxprint - allocate a __counted string buffer and print label
1707 * @strp: buffer to write to.
1708 * @ns: namespace profile is being viewed from
1709 * @label: label to view (NOT NULL)
1710 * @flags: flags controlling what label info is printed
1711 * @gfp: kernel memory allocation type
1713 * Returns: size of name written or would be written if larger than
1716 int aa_label_acntsxprint(char __counted **strp, struct aa_ns *ns,
1717 struct aa_label *label, int flags, gfp_t gfp)
1724 size = aa_label_snxprint(NULL, 0, ns, label, flags);
1728 *strp = aa_str_alloc(size + 1, gfp);
1731 return aa_label_snxprint(*strp, size + 1, ns, label, flags);
1735 void aa_label_xaudit(struct audit_buffer *ab, struct aa_ns *ns,
1736 struct aa_label *label, int flags, gfp_t gfp)
1745 if (!use_label_hname(ns, label, flags) ||
1746 display_mode(ns, label, flags)) {
1747 len = aa_label_asxprint(&name, ns, label, flags, gfp);
1749 AA_DEBUG("label print error");
1754 str = (char *) label->hname;
1757 if (audit_string_contains_control(str, len))
1758 audit_log_n_hex(ab, str, len);
1760 audit_log_n_string(ab, str, len);
1765 void aa_label_seq_xprint(struct seq_file *f, struct aa_ns *ns,
1766 struct aa_label *label, int flags, gfp_t gfp)
1771 if (!use_label_hname(ns, label, flags)) {
1775 len = aa_label_asxprint(&str, ns, label, flags, gfp);
1777 AA_DEBUG("label print error");
1782 } else if (display_mode(ns, label, flags))
1783 seq_printf(f, "%s (%s)", label->hname,
1784 label_modename(ns, label, flags));
1786 seq_puts(f, label->hname);
1789 void aa_label_xprintk(struct aa_ns *ns, struct aa_label *label, int flags,
1794 if (!use_label_hname(ns, label, flags)) {
1798 len = aa_label_asxprint(&str, ns, label, flags, gfp);
1800 AA_DEBUG("label print error");
1805 } else if (display_mode(ns, label, flags))
1806 pr_info("%s (%s)", label->hname,
1807 label_modename(ns, label, flags));
1809 pr_info("%s", label->hname);
1812 void aa_label_audit(struct audit_buffer *ab, struct aa_label *label, gfp_t gfp)
1814 struct aa_ns *ns = aa_get_current_ns();
1816 aa_label_xaudit(ab, ns, label, FLAG_VIEW_SUBNS, gfp);
1820 void aa_label_seq_print(struct seq_file *f, struct aa_label *label, gfp_t gfp)
1822 struct aa_ns *ns = aa_get_current_ns();
1824 aa_label_seq_xprint(f, ns, label, FLAG_VIEW_SUBNS, gfp);
1828 void aa_label_printk(struct aa_label *label, gfp_t gfp)
1830 struct aa_ns *ns = aa_get_current_ns();
1832 aa_label_xprintk(ns, label, FLAG_VIEW_SUBNS, gfp);
1836 static int label_count_strn_entries(const char *str, size_t n)
1838 const char *end = str + n;
1844 for (split = aa_label_strn_split(str, end - str);
1846 split = aa_label_strn_split(str, end - str)) {
1855 * ensure stacks with components like
1857 * have :ns: applied to both 'A' and 'B' by making the lookup relative
1858 * to the base if the lookup specifies an ns, else making the stacked lookup
1859 * relative to the last embedded ns in the string.
1861 static struct aa_profile *fqlookupn_profile(struct aa_label *base,
1862 struct aa_label *currentbase,
1863 const char *str, size_t n)
1865 const char *first = skipn_spaces(str, n);
1867 if (first && *first == ':')
1868 return aa_fqlookupn_profile(base, str, n);
1870 return aa_fqlookupn_profile(currentbase, str, n);
1874 * aa_label_strn_parse - parse, validate and convert a text string to a label
1875 * @base: base label to use for lookups (NOT NULL)
1876 * @str: null terminated text string (NOT NULL)
1877 * @n: length of str to parse, will stop at \0 if encountered before n
1878 * @gfp: allocation type
1879 * @create: true if should create compound labels if they don't exist
1880 * @force_stack: true if should stack even if no leading &
1882 * Returns: the matching refcounted label if present
1885 struct aa_label *aa_label_strn_parse(struct aa_label *base, const char *str,
1886 size_t n, gfp_t gfp, bool create,
1889 DEFINE_VEC(profile, vec);
1890 struct aa_label *label, *currbase = base;
1891 int i, len, stack = 0, error;
1892 const char *end = str + n;
1898 str = skipn_spaces(str, n);
1899 if (str == NULL || (AA_DEBUG_LABEL && *str == '_' &&
1900 base != &root_ns->unconfined->label))
1901 return ERR_PTR(-EINVAL);
1903 len = label_count_strn_entries(str, end - str);
1904 if (*str == '&' || force_stack) {
1905 /* stack on top of base */
1912 error = vec_setup(profile, vec, len, gfp);
1914 return ERR_PTR(error);
1916 for (i = 0; i < stack; i++)
1917 vec[i] = aa_get_profile(base->vec[i]);
1919 for (split = aa_label_strn_split(str, end - str), i = stack;
1920 split && i < len; i++) {
1921 vec[i] = fqlookupn_profile(base, currbase, str, split - str);
1925 * if component specified a new ns it becomes the new base
1926 * so that subsequent lookups are relative to it
1928 if (vec[i]->ns != labels_ns(currbase))
1929 currbase = &vec[i]->label;
1931 split = aa_label_strn_split(str, end - str);
1933 /* last element doesn't have a split */
1935 vec[i] = fqlookupn_profile(base, currbase, str, end - str);
1940 /* no need to free vec as len < LOCAL_VEC_ENTRIES */
1941 return &vec[0]->label;
1943 len -= aa_vec_unique(vec, len, VEC_FLAG_TERMINATE);
1944 /* TODO: deal with reference labels */
1946 label = aa_get_label(&vec[0]->label);
1951 label = aa_vec_find_or_create_label(vec, len, gfp);
1953 label = vec_find(vec, len);
1958 /* use adjusted len from after vec_unique, not original */
1959 vec_cleanup(profile, vec, len);
1963 label = ERR_PTR(-ENOENT);
1967 struct aa_label *aa_label_parse(struct aa_label *base, const char *str,
1968 gfp_t gfp, bool create, bool force_stack)
1970 return aa_label_strn_parse(base, str, strlen(str), gfp, create,
1975 * aa_labelset_destroy - remove all labels from the label set
1976 * @ls: label set to cleanup (NOT NULL)
1978 * Labels that are removed from the set may still exist beyond the set
1979 * being destroyed depending on their reference counting
1981 void aa_labelset_destroy(struct aa_labelset *ls)
1983 struct rb_node *node;
1984 unsigned long flags;
1988 write_lock_irqsave(&ls->lock, flags);
1989 for (node = rb_first(&ls->root); node; node = rb_first(&ls->root)) {
1990 struct aa_label *this = rb_entry(node, struct aa_label, node);
1992 if (labels_ns(this) != root_ns)
1993 __label_remove(this,
1994 ns_unconfined(labels_ns(this)->parent));
1996 __label_remove(this, NULL);
1998 write_unlock_irqrestore(&ls->lock, flags);
2002 * @ls: labelset to init (NOT NULL)
2004 void aa_labelset_init(struct aa_labelset *ls)
2008 rwlock_init(&ls->lock);
2012 static struct aa_label *labelset_next_stale(struct aa_labelset *ls)
2014 struct aa_label *label;
2015 struct rb_node *node;
2016 unsigned long flags;
2020 read_lock_irqsave(&ls->lock, flags);
2022 __labelset_for_each(ls, node) {
2023 label = rb_entry(node, struct aa_label, node);
2024 if ((label_is_stale(label) ||
2025 vec_is_stale(label->vec, label->size)) &&
2026 __aa_get_label(label))
2033 read_unlock_irqrestore(&ls->lock, flags);
2039 * __label_update - insert updated version of @label into labelset
2040 * @label - the label to update/replace
2042 * Returns: new label that is up to date
2043 * else NULL on failure
2045 * Requires: @ns lock be held
2047 * Note: worst case is the stale @label does not get updated and has
2048 * to be updated at a later time.
2050 static struct aa_label *__label_update(struct aa_label *label)
2052 struct aa_label *new, *tmp;
2053 struct aa_labelset *ls;
2054 unsigned long flags;
2055 int i, invcount = 0;
2058 AA_BUG(!mutex_is_locked(&labels_ns(label)->lock));
2060 new = aa_label_alloc(label->size, label->proxy, GFP_KERNEL);
2065 * while holding the ns_lock will stop profile replacement, removal,
2066 * and label updates, label merging and removal can be occurring
2068 ls = labels_set(label);
2069 write_lock_irqsave(&ls->lock, flags);
2070 for (i = 0; i < label->size; i++) {
2071 AA_BUG(!label->vec[i]);
2072 new->vec[i] = aa_get_newest_profile(label->vec[i]);
2073 AA_BUG(!new->vec[i]);
2074 AA_BUG(!new->vec[i]->label.proxy);
2075 AA_BUG(!new->vec[i]->label.proxy->label);
2076 if (new->vec[i]->label.proxy != label->vec[i]->label.proxy)
2080 /* updated stale label by being removed/renamed from labelset */
2082 new->size -= aa_vec_unique(&new->vec[0], new->size,
2083 VEC_FLAG_TERMINATE);
2084 /* TODO: deal with reference labels */
2085 if (new->size == 1) {
2086 tmp = aa_get_label(&new->vec[0]->label);
2087 AA_BUG(tmp == label);
2090 if (labels_set(label) != labels_set(new)) {
2091 write_unlock_irqrestore(&ls->lock, flags);
2092 tmp = aa_label_insert(labels_set(new), new);
2093 write_lock_irqsave(&ls->lock, flags);
2097 AA_BUG(labels_ns(label) != labels_ns(new));
2099 tmp = __label_insert(labels_set(label), new, true);
2101 /* ensure label is removed, and redirected correctly */
2102 __label_remove(label, tmp);
2103 write_unlock_irqrestore(&ls->lock, flags);
2104 label_free_or_put_new(tmp, new);
2110 * __labelset_update - update labels in @ns
2111 * @ns: namespace to update labels in (NOT NULL)
2113 * Requires: @ns lock be held
2115 * Walk the labelset ensuring that all labels are up to date and valid
2116 * Any label that has a stale component is marked stale and replaced and
2117 * by an updated version.
2119 * If failures happen due to memory pressures then stale labels will
2120 * be left in place until the next pass.
2122 static void __labelset_update(struct aa_ns *ns)
2124 struct aa_label *label;
2127 AA_BUG(!mutex_is_locked(&ns->lock));
2130 label = labelset_next_stale(&ns->labels);
2132 struct aa_label *l = __label_update(label);
2135 aa_put_label(label);
2141 * __aa_labelset_update_subtree - update all labels with a stale component
2142 * @ns: ns to start update at (NOT NULL)
2144 * Requires: @ns lock be held
2146 * Invalidates labels based on @p in @ns and any children namespaces.
2148 void __aa_labelset_update_subtree(struct aa_ns *ns)
2150 struct aa_ns *child;
2153 AA_BUG(!mutex_is_locked(&ns->lock));
2155 __labelset_update(ns);
2157 list_for_each_entry(child, &ns->sub_ns, base.list) {
2158 mutex_lock_nested(&child->lock, child->level);
2159 __aa_labelset_update_subtree(child);
2160 mutex_unlock(&child->lock);