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 static inline bool label_is_visible(struct aa_profile *profile,
1260 struct aa_label *label)
1262 return aa_ns_visible(profile->ns, labels_ns(label), true);
1265 /* match a profile and its associated ns component if needed
1266 * Assumes visibility test has already been done.
1267 * If a subns profile is not to be matched should be prescreened with
1270 static inline unsigned int match_component(struct aa_profile *profile,
1271 struct aa_profile *tp,
1274 const char *ns_name;
1276 if (profile->ns == tp->ns)
1277 return aa_dfa_match(profile->policy.dfa, state, tp->base.hname);
1279 /* try matching with namespace name and then profile */
1280 ns_name = aa_ns_name(profile->ns, tp->ns, true);
1281 state = aa_dfa_match_len(profile->policy.dfa, state, ":", 1);
1282 state = aa_dfa_match(profile->policy.dfa, state, ns_name);
1283 state = aa_dfa_match_len(profile->policy.dfa, state, ":", 1);
1284 return aa_dfa_match(profile->policy.dfa, state, tp->base.hname);
1288 * label_compound_match - find perms for full compound label
1289 * @profile: profile to find perms for
1290 * @label: label to check access permissions for
1291 * @start: state to start match in
1292 * @subns: whether to do permission checks on components in a subns
1293 * @request: permissions to request
1294 * @perms: perms struct to set
1296 * Returns: 0 on success else ERROR
1298 * For the label A//&B//&C this does the perm match for A//&B//&C
1299 * @perms should be preinitialized with allperms OR a previous permission
1300 * check to be stacked.
1302 static int label_compound_match(struct aa_profile *profile,
1303 struct aa_label *label,
1304 unsigned int state, bool subns, u32 request,
1305 struct aa_perms *perms)
1307 struct aa_profile *tp;
1310 /* find first subcomponent that is visible */
1311 label_for_each(i, label, tp) {
1312 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1314 state = match_component(profile, tp, state);
1320 /* no component visible */
1325 label_for_each_cont(i, label, tp) {
1326 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1328 state = aa_dfa_match(profile->policy.dfa, state, "//&");
1329 state = match_component(profile, tp, state);
1333 aa_compute_perms(profile->policy.dfa, state, perms);
1334 aa_apply_modes_to_perms(profile, perms);
1335 if ((perms->allow & request) != request)
1346 * label_components_match - find perms for all subcomponents of a label
1347 * @profile: profile to find perms for
1348 * @label: label to check access permissions for
1349 * @start: state to start match in
1350 * @subns: whether to do permission checks on components in a subns
1351 * @request: permissions to request
1352 * @perms: an initialized perms struct to add accumulation to
1354 * Returns: 0 on success else ERROR
1356 * For the label A//&B//&C this does the perm match for each of A and B and C
1357 * @perms should be preinitialized with allperms OR a previous permission
1358 * check to be stacked.
1360 static int label_components_match(struct aa_profile *profile,
1361 struct aa_label *label, unsigned int start,
1362 bool subns, u32 request,
1363 struct aa_perms *perms)
1365 struct aa_profile *tp;
1367 struct aa_perms tmp;
1368 unsigned int state = 0;
1370 /* find first subcomponent to test */
1371 label_for_each(i, label, tp) {
1372 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1374 state = match_component(profile, tp, start);
1380 /* no subcomponents visible - no change in perms */
1384 aa_compute_perms(profile->policy.dfa, state, &tmp);
1385 aa_apply_modes_to_perms(profile, &tmp);
1386 aa_perms_accum(perms, &tmp);
1387 label_for_each_cont(i, label, tp) {
1388 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1390 state = match_component(profile, tp, start);
1393 aa_compute_perms(profile->policy.dfa, state, &tmp);
1394 aa_apply_modes_to_perms(profile, &tmp);
1395 aa_perms_accum(perms, &tmp);
1398 if ((perms->allow & request) != request)
1409 * aa_label_match - do a multi-component label match
1410 * @profile: profile to match against (NOT NULL)
1411 * @label: label to match (NOT NULL)
1412 * @state: state to start in
1413 * @subns: whether to match subns components
1414 * @request: permission request
1415 * @perms: Returns computed perms (NOT NULL)
1417 * Returns: the state the match finished in, may be the none matching state
1419 int aa_label_match(struct aa_profile *profile, struct aa_label *label,
1420 unsigned int state, bool subns, u32 request,
1421 struct aa_perms *perms)
1423 int error = label_compound_match(profile, label, state, subns, request,
1429 return label_components_match(profile, label, state, subns, request,
1435 * aa_update_label_name - update a label to have a stored name
1436 * @ns: ns being viewed from (NOT NULL)
1437 * @label: label to update (NOT NULL)
1438 * @gfp: type of memory allocation
1440 * Requires: labels_set(label) not locked in caller
1442 * note: only updates the label name if it does not have a name already
1443 * and if it is in the labelset
1445 bool aa_update_label_name(struct aa_ns *ns, struct aa_label *label, gfp_t gfp)
1447 struct aa_labelset *ls;
1448 unsigned long flags;
1449 char __counted *name;
1455 if (label->hname || labels_ns(label) != ns)
1458 if (aa_label_acntsxprint(&name, ns, label, FLAGS_NONE, gfp) < 0)
1461 ls = labels_set(label);
1462 write_lock_irqsave(&ls->lock, flags);
1463 if (!label->hname && label->flags & FLAG_IN_TREE) {
1464 label->hname = name;
1468 write_unlock_irqrestore(&ls->lock, flags);
1474 * cached label name is present and visible
1475 * @label->hname only exists if label is namespace hierachical
1477 static inline bool use_label_hname(struct aa_ns *ns, struct aa_label *label,
1480 if (label->hname && (!ns || labels_ns(label) == ns) &&
1481 !(flags & ~FLAG_SHOW_MODE))
1487 /* helper macro for snprint routines */
1488 #define update_for_len(total, len, size, str) \
1490 size_t ulen = len; \
1494 ulen = min(ulen, size); \
1500 * aa_profile_snxprint - print a profile name to a buffer
1501 * @str: buffer to write to. (MAY BE NULL if @size == 0)
1502 * @size: size of buffer
1503 * @view: namespace profile is being viewed from
1504 * @profile: profile to view (NOT NULL)
1505 * @flags: whether to include the mode string
1506 * @prev_ns: last ns printed when used in compound print
1508 * Returns: size of name written or would be written if larger than
1511 * Note: will not print anything if the profile is not visible
1513 static int aa_profile_snxprint(char *str, size_t size, struct aa_ns *view,
1514 struct aa_profile *profile, int flags,
1515 struct aa_ns **prev_ns)
1517 const char *ns_name = NULL;
1519 AA_BUG(!str && size != 0);
1523 view = profiles_ns(profile);
1525 if (view != profile->ns &&
1526 (!prev_ns || (*prev_ns != profile->ns))) {
1528 *prev_ns = profile->ns;
1529 ns_name = aa_ns_name(view, profile->ns,
1530 flags & FLAG_VIEW_SUBNS);
1531 if (ns_name == aa_hidden_ns_name) {
1532 if (flags & FLAG_HIDDEN_UNCONFINED)
1533 return snprintf(str, size, "%s", "unconfined");
1534 return snprintf(str, size, "%s", ns_name);
1538 if ((flags & FLAG_SHOW_MODE) && profile != profile->ns->unconfined) {
1539 const char *modestr = aa_profile_mode_names[profile->mode];
1542 return snprintf(str, size, ":%s:%s (%s)", ns_name,
1543 profile->base.hname, modestr);
1544 return snprintf(str, size, "%s (%s)", profile->base.hname,
1549 return snprintf(str, size, ":%s:%s", ns_name,
1550 profile->base.hname);
1551 return snprintf(str, size, "%s", profile->base.hname);
1554 static const char *label_modename(struct aa_ns *ns, struct aa_label *label,
1557 struct aa_profile *profile;
1559 int mode = -1, count = 0;
1561 label_for_each(i, label, profile) {
1562 if (aa_ns_visible(ns, profile->ns, flags & FLAG_VIEW_SUBNS)) {
1564 if (profile == profile->ns->unconfined)
1565 /* special case unconfined so stacks with
1566 * unconfined don't report as mixed. ie.
1567 * profile_foo//&:ns1:unconfined (mixed)
1571 mode = profile->mode;
1572 else if (mode != profile->mode)
1580 /* everything was unconfined */
1581 mode = APPARMOR_UNCONFINED;
1583 return aa_profile_mode_names[mode];
1586 /* if any visible label is not unconfined the display_mode returns true */
1587 static inline bool display_mode(struct aa_ns *ns, struct aa_label *label,
1590 if ((flags & FLAG_SHOW_MODE)) {
1591 struct aa_profile *profile;
1594 label_for_each(i, label, profile) {
1595 if (aa_ns_visible(ns, profile->ns,
1596 flags & FLAG_VIEW_SUBNS) &&
1597 profile != profile->ns->unconfined)
1600 /* only ns->unconfined in set of profiles in ns */
1608 * aa_label_snxprint - print a label name to a string buffer
1609 * @str: buffer to write to. (MAY BE NULL if @size == 0)
1610 * @size: size of buffer
1611 * @ns: namespace profile is being viewed from
1612 * @label: label to view (NOT NULL)
1613 * @flags: whether to include the mode string
1615 * Returns: size of name written or would be written if larger than
1618 * Note: labels do not have to be strictly hierarchical to the ns as
1619 * objects may be shared across different namespaces and thus
1620 * pickup labeling from each ns. If a particular part of the
1621 * label is not visible it will just be excluded. And if none
1622 * of the label is visible "---" will be used.
1624 int aa_label_snxprint(char *str, size_t size, struct aa_ns *ns,
1625 struct aa_label *label, int flags)
1627 struct aa_profile *profile;
1628 struct aa_ns *prev_ns = NULL;
1630 int count = 0, total = 0;
1633 AA_BUG(!str && size != 0);
1636 if (AA_DEBUG_LABEL && (flags & FLAG_ABS_ROOT)) {
1638 len = snprintf(str, size, "_");
1639 update_for_len(total, len, size, str);
1641 ns = labels_ns(label);
1644 label_for_each(i, label, profile) {
1645 if (aa_ns_visible(ns, profile->ns, flags & FLAG_VIEW_SUBNS)) {
1647 len = snprintf(str, size, "//&");
1648 update_for_len(total, len, size, str);
1650 len = aa_profile_snxprint(str, size, ns, profile,
1651 flags & FLAG_VIEW_SUBNS,
1653 update_for_len(total, len, size, str);
1659 if (flags & FLAG_HIDDEN_UNCONFINED)
1660 return snprintf(str, size, "%s", "unconfined");
1661 return snprintf(str, size, "%s", aa_hidden_ns_name);
1664 /* count == 1 && ... is for backwards compat where the mode
1665 * is not displayed for 'unconfined' in the current ns
1667 if (display_mode(ns, label, flags)) {
1668 len = snprintf(str, size, " (%s)",
1669 label_modename(ns, label, flags));
1670 update_for_len(total, len, size, str);
1675 #undef update_for_len
1678 * aa_label_asxprint - allocate a string buffer and print label into it
1679 * @strp: Returns - the allocated buffer with the label name. (NOT NULL)
1680 * @ns: namespace profile is being viewed from
1681 * @label: label to view (NOT NULL)
1682 * @flags: flags controlling what label info is printed
1683 * @gfp: kernel memory allocation type
1685 * Returns: size of name written or would be written if larger than
1688 int aa_label_asxprint(char **strp, struct aa_ns *ns, struct aa_label *label,
1689 int flags, gfp_t gfp)
1696 size = aa_label_snxprint(NULL, 0, ns, label, flags);
1700 *strp = kmalloc(size + 1, gfp);
1703 return aa_label_snxprint(*strp, size + 1, ns, label, flags);
1707 * aa_label_acntsxprint - allocate a __counted string buffer and print label
1708 * @strp: buffer to write to.
1709 * @ns: namespace profile is being viewed from
1710 * @label: label to view (NOT NULL)
1711 * @flags: flags controlling what label info is printed
1712 * @gfp: kernel memory allocation type
1714 * Returns: size of name written or would be written if larger than
1717 int aa_label_acntsxprint(char __counted **strp, struct aa_ns *ns,
1718 struct aa_label *label, int flags, gfp_t gfp)
1725 size = aa_label_snxprint(NULL, 0, ns, label, flags);
1729 *strp = aa_str_alloc(size + 1, gfp);
1732 return aa_label_snxprint(*strp, size + 1, ns, label, flags);
1736 void aa_label_xaudit(struct audit_buffer *ab, struct aa_ns *ns,
1737 struct aa_label *label, int flags, gfp_t gfp)
1746 if (!use_label_hname(ns, label, flags) ||
1747 display_mode(ns, label, flags)) {
1748 len = aa_label_asxprint(&name, ns, label, flags, gfp);
1750 AA_DEBUG("label print error");
1755 str = (char *) label->hname;
1758 if (audit_string_contains_control(str, len))
1759 audit_log_n_hex(ab, str, len);
1761 audit_log_n_string(ab, str, len);
1766 void aa_label_seq_xprint(struct seq_file *f, struct aa_ns *ns,
1767 struct aa_label *label, int flags, gfp_t gfp)
1772 if (!use_label_hname(ns, label, flags)) {
1776 len = aa_label_asxprint(&str, ns, label, flags, gfp);
1778 AA_DEBUG("label print error");
1783 } else if (display_mode(ns, label, flags))
1784 seq_printf(f, "%s (%s)", label->hname,
1785 label_modename(ns, label, flags));
1787 seq_puts(f, label->hname);
1790 void aa_label_xprintk(struct aa_ns *ns, struct aa_label *label, int flags,
1795 if (!use_label_hname(ns, label, flags)) {
1799 len = aa_label_asxprint(&str, ns, label, flags, gfp);
1801 AA_DEBUG("label print error");
1806 } else if (display_mode(ns, label, flags))
1807 pr_info("%s (%s)", label->hname,
1808 label_modename(ns, label, flags));
1810 pr_info("%s", label->hname);
1813 void aa_label_audit(struct audit_buffer *ab, struct aa_label *label, gfp_t gfp)
1815 struct aa_ns *ns = aa_get_current_ns();
1817 aa_label_xaudit(ab, ns, label, FLAG_VIEW_SUBNS, gfp);
1821 void aa_label_seq_print(struct seq_file *f, struct aa_label *label, gfp_t gfp)
1823 struct aa_ns *ns = aa_get_current_ns();
1825 aa_label_seq_xprint(f, ns, label, FLAG_VIEW_SUBNS, gfp);
1829 void aa_label_printk(struct aa_label *label, gfp_t gfp)
1831 struct aa_ns *ns = aa_get_current_ns();
1833 aa_label_xprintk(ns, label, FLAG_VIEW_SUBNS, gfp);
1837 static int label_count_strn_entries(const char *str, size_t n)
1839 const char *end = str + n;
1845 for (split = aa_label_strn_split(str, end - str);
1847 split = aa_label_strn_split(str, end - str)) {
1856 * ensure stacks with components like
1858 * have :ns: applied to both 'A' and 'B' by making the lookup relative
1859 * to the base if the lookup specifies an ns, else making the stacked lookup
1860 * relative to the last embedded ns in the string.
1862 static struct aa_profile *fqlookupn_profile(struct aa_label *base,
1863 struct aa_label *currentbase,
1864 const char *str, size_t n)
1866 const char *first = skipn_spaces(str, n);
1868 if (first && *first == ':')
1869 return aa_fqlookupn_profile(base, str, n);
1871 return aa_fqlookupn_profile(currentbase, str, n);
1875 * aa_label_strn_parse - parse, validate and convert a text string to a label
1876 * @base: base label to use for lookups (NOT NULL)
1877 * @str: null terminated text string (NOT NULL)
1878 * @n: length of str to parse, will stop at \0 if encountered before n
1879 * @gfp: allocation type
1880 * @create: true if should create compound labels if they don't exist
1881 * @force_stack: true if should stack even if no leading &
1883 * Returns: the matching refcounted label if present
1886 struct aa_label *aa_label_strn_parse(struct aa_label *base, const char *str,
1887 size_t n, gfp_t gfp, bool create,
1890 DEFINE_VEC(profile, vec);
1891 struct aa_label *label, *currbase = base;
1892 int i, len, stack = 0, error;
1893 const char *end = str + n;
1899 str = skipn_spaces(str, n);
1900 if (str == NULL || (AA_DEBUG_LABEL && *str == '_' &&
1901 base != &root_ns->unconfined->label))
1902 return ERR_PTR(-EINVAL);
1904 len = label_count_strn_entries(str, end - str);
1905 if (*str == '&' || force_stack) {
1906 /* stack on top of base */
1913 error = vec_setup(profile, vec, len, gfp);
1915 return ERR_PTR(error);
1917 for (i = 0; i < stack; i++)
1918 vec[i] = aa_get_profile(base->vec[i]);
1920 for (split = aa_label_strn_split(str, end - str), i = stack;
1921 split && i < len; i++) {
1922 vec[i] = fqlookupn_profile(base, currbase, str, split - str);
1926 * if component specified a new ns it becomes the new base
1927 * so that subsequent lookups are relative to it
1929 if (vec[i]->ns != labels_ns(currbase))
1930 currbase = &vec[i]->label;
1932 split = aa_label_strn_split(str, end - str);
1934 /* last element doesn't have a split */
1936 vec[i] = fqlookupn_profile(base, currbase, str, end - str);
1941 /* no need to free vec as len < LOCAL_VEC_ENTRIES */
1942 return &vec[0]->label;
1944 len -= aa_vec_unique(vec, len, VEC_FLAG_TERMINATE);
1945 /* TODO: deal with reference labels */
1947 label = aa_get_label(&vec[0]->label);
1952 label = aa_vec_find_or_create_label(vec, len, gfp);
1954 label = vec_find(vec, len);
1959 /* use adjusted len from after vec_unique, not original */
1960 vec_cleanup(profile, vec, len);
1964 label = ERR_PTR(-ENOENT);
1968 struct aa_label *aa_label_parse(struct aa_label *base, const char *str,
1969 gfp_t gfp, bool create, bool force_stack)
1971 return aa_label_strn_parse(base, str, strlen(str), gfp, create,
1976 * aa_labelset_destroy - remove all labels from the label set
1977 * @ls: label set to cleanup (NOT NULL)
1979 * Labels that are removed from the set may still exist beyond the set
1980 * being destroyed depending on their reference counting
1982 void aa_labelset_destroy(struct aa_labelset *ls)
1984 struct rb_node *node;
1985 unsigned long flags;
1989 write_lock_irqsave(&ls->lock, flags);
1990 for (node = rb_first(&ls->root); node; node = rb_first(&ls->root)) {
1991 struct aa_label *this = rb_entry(node, struct aa_label, node);
1993 if (labels_ns(this) != root_ns)
1994 __label_remove(this,
1995 ns_unconfined(labels_ns(this)->parent));
1997 __label_remove(this, NULL);
1999 write_unlock_irqrestore(&ls->lock, flags);
2003 * @ls: labelset to init (NOT NULL)
2005 void aa_labelset_init(struct aa_labelset *ls)
2009 rwlock_init(&ls->lock);
2013 static struct aa_label *labelset_next_stale(struct aa_labelset *ls)
2015 struct aa_label *label;
2016 struct rb_node *node;
2017 unsigned long flags;
2021 read_lock_irqsave(&ls->lock, flags);
2023 __labelset_for_each(ls, node) {
2024 label = rb_entry(node, struct aa_label, node);
2025 if ((label_is_stale(label) ||
2026 vec_is_stale(label->vec, label->size)) &&
2027 __aa_get_label(label))
2034 read_unlock_irqrestore(&ls->lock, flags);
2040 * __label_update - insert updated version of @label into labelset
2041 * @label - the label to update/replace
2043 * Returns: new label that is up to date
2044 * else NULL on failure
2046 * Requires: @ns lock be held
2048 * Note: worst case is the stale @label does not get updated and has
2049 * to be updated at a later time.
2051 static struct aa_label *__label_update(struct aa_label *label)
2053 struct aa_label *new, *tmp;
2054 struct aa_labelset *ls;
2055 unsigned long flags;
2056 int i, invcount = 0;
2059 AA_BUG(!mutex_is_locked(&labels_ns(label)->lock));
2061 new = aa_label_alloc(label->size, label->proxy, GFP_KERNEL);
2066 * while holding the ns_lock will stop profile replacement, removal,
2067 * and label updates, label merging and removal can be occurring
2069 ls = labels_set(label);
2070 write_lock_irqsave(&ls->lock, flags);
2071 for (i = 0; i < label->size; i++) {
2072 AA_BUG(!label->vec[i]);
2073 new->vec[i] = aa_get_newest_profile(label->vec[i]);
2074 AA_BUG(!new->vec[i]);
2075 AA_BUG(!new->vec[i]->label.proxy);
2076 AA_BUG(!new->vec[i]->label.proxy->label);
2077 if (new->vec[i]->label.proxy != label->vec[i]->label.proxy)
2081 /* updated stale label by being removed/renamed from labelset */
2083 new->size -= aa_vec_unique(&new->vec[0], new->size,
2084 VEC_FLAG_TERMINATE);
2085 /* TODO: deal with reference labels */
2086 if (new->size == 1) {
2087 tmp = aa_get_label(&new->vec[0]->label);
2088 AA_BUG(tmp == label);
2091 if (labels_set(label) != labels_set(new)) {
2092 write_unlock_irqrestore(&ls->lock, flags);
2093 tmp = aa_label_insert(labels_set(new), new);
2094 write_lock_irqsave(&ls->lock, flags);
2098 AA_BUG(labels_ns(label) != labels_ns(new));
2100 tmp = __label_insert(labels_set(label), new, true);
2102 /* ensure label is removed, and redirected correctly */
2103 __label_remove(label, tmp);
2104 write_unlock_irqrestore(&ls->lock, flags);
2105 label_free_or_put_new(tmp, new);
2111 * __labelset_update - update labels in @ns
2112 * @ns: namespace to update labels in (NOT NULL)
2114 * Requires: @ns lock be held
2116 * Walk the labelset ensuring that all labels are up to date and valid
2117 * Any label that has a stale component is marked stale and replaced and
2118 * by an updated version.
2120 * If failures happen due to memory pressures then stale labels will
2121 * be left in place until the next pass.
2123 static void __labelset_update(struct aa_ns *ns)
2125 struct aa_label *label;
2128 AA_BUG(!mutex_is_locked(&ns->lock));
2131 label = labelset_next_stale(&ns->labels);
2133 struct aa_label *l = __label_update(label);
2136 aa_put_label(label);
2142 * __aa_labelset_update_subtree - update all labels with a stale component
2143 * @ns: ns to start update at (NOT NULL)
2145 * Requires: @ns lock be held
2147 * Invalidates labels based on @p in @ns and any children namespaces.
2149 void __aa_labelset_update_subtree(struct aa_ns *ns)
2151 struct aa_ns *child;
2154 AA_BUG(!mutex_is_locked(&ns->lock));
2156 __labelset_update(ns);
2158 list_for_each_entry(child, &ns->sub_ns, base.list) {
2159 mutex_lock_nested(&child->lock, child->level);
2160 __aa_labelset_update_subtree(child);
2161 mutex_unlock(&child->lock);