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 bool vec_unconfined(struct aa_profile **vec, int n)
206 for (i = 0; i < n; i++) {
207 if (!profile_unconfined(vec[i]))
214 static int sort_cmp(const void *a, const void *b)
216 return profile_cmp(*(struct aa_profile **)a, *(struct aa_profile **)b);
220 * assumes vec is sorted
221 * Assumes @vec has null terminator at vec[n], and will null terminate
224 static inline int unique(struct aa_profile **vec, int n)
226 int i, pos, dups = 0;
232 for (i = 1; i < n; i++) {
233 int res = profile_cmp(vec[pos], vec[i]);
235 AA_BUG(res > 0, "vec not sorted");
238 aa_put_profile(vec[i]);
253 * aa_vec_unique - canonical sort and unique a list of profiles
254 * @n: number of refcounted profiles in the list (@n > 0)
255 * @vec: list of profiles to sort and merge
257 * Returns: the number of duplicates eliminated == references put
259 * If @flags & VEC_FLAG_TERMINATE @vec has null terminator at vec[n], and will
260 * null terminate vec[n - dups]
262 int aa_vec_unique(struct aa_profile **vec, int n, int flags)
269 /* vecs are usually small and inorder, have a fallback for larger */
271 sort(vec, n, sizeof(struct aa_profile *), sort_cmp, NULL);
272 dups = unique(vec, n);
276 /* insertion sort + unique in one */
277 for (i = 1; i < n; i++) {
278 struct aa_profile *tmp = vec[i];
281 for (pos = i - 1 - dups; pos >= 0; pos--) {
282 int res = profile_cmp(vec[pos], tmp);
285 /* drop duplicate entry */
292 /* pos is at entry < tmp, or index -1. Set to insert pos */
295 for (j = i - dups; j > pos; j--)
305 if (flags & VEC_FLAG_TERMINATE)
306 vec[n - dups] = NULL;
312 static void label_destroy(struct aa_label *label)
314 struct aa_label *tmp;
318 if (!label_isprofile(label)) {
319 struct aa_profile *profile;
322 aa_put_str(label->hname);
324 label_for_each(i, label, profile) {
325 aa_put_profile(profile);
326 label->vec[i.i] = (struct aa_profile *)
327 (LABEL_POISON + (long) i.i);
331 if (rcu_dereference_protected(label->proxy->label, true) == label)
332 rcu_assign_pointer(label->proxy->label, NULL);
334 aa_free_secid(label->secid);
336 tmp = rcu_dereference_protected(label->proxy->label, true);
338 rcu_assign_pointer(label->proxy->label, NULL);
340 aa_put_proxy(label->proxy);
341 label->proxy = (struct aa_proxy *) PROXY_POISON + 1;
344 void aa_label_free(struct aa_label *label)
349 label_destroy(label);
353 static void label_free_switch(struct aa_label *label)
355 if (label->flags & FLAG_NS_COUNT)
356 aa_free_ns(labels_ns(label));
357 else if (label_isprofile(label))
358 aa_free_profile(labels_profile(label));
360 aa_label_free(label);
363 static void label_free_rcu(struct rcu_head *head)
365 struct aa_label *label = container_of(head, struct aa_label, rcu);
367 if (label->flags & FLAG_IN_TREE)
368 (void) aa_label_remove(label);
369 label_free_switch(label);
372 void aa_label_kref(struct kref *kref)
374 struct aa_label *label = container_of(kref, struct aa_label, count);
375 struct aa_ns *ns = labels_ns(label);
378 /* never live, no rcu callback needed, just using the fn */
379 label_free_switch(label);
382 /* TODO: update labels_profile macro so it works here */
383 AA_BUG(label_isprofile(label) &&
384 on_list_rcu(&label->vec[0]->base.profiles));
385 AA_BUG(label_isprofile(label) &&
386 on_list_rcu(&label->vec[0]->base.list));
388 /* TODO: if compound label and not stale add to reclaim cache */
389 call_rcu(&label->rcu, label_free_rcu);
392 static void label_free_or_put_new(struct aa_label *label, struct aa_label *new)
395 /* need to free directly to break circular ref with proxy */
401 bool aa_label_init(struct aa_label *label, int size, gfp_t gfp)
406 if (aa_alloc_secid(label, gfp) < 0)
409 label->size = size; /* doesn't include null */
410 label->vec[size] = NULL; /* null terminate */
411 kref_init(&label->count);
412 RB_CLEAR_NODE(&label->node);
418 * aa_label_alloc - allocate a label with a profile vector of @size length
419 * @size: size of profile vector in the label
420 * @proxy: proxy to use OR null if to allocate a new one
421 * @gfp: memory allocation type
424 * else NULL if failed
426 struct aa_label *aa_label_alloc(int size, struct aa_proxy *proxy, gfp_t gfp)
428 struct aa_label *new;
432 /* + 1 for null terminator entry on vec */
433 new = kzalloc(sizeof(*new) + sizeof(struct aa_profile *) * (size + 1),
435 AA_DEBUG("%s (%p)\n", __func__, new);
439 if (!aa_label_init(new, size, gfp))
443 proxy = aa_alloc_proxy(new, gfp);
448 /* just set new's proxy, don't redirect proxy here if it was passed in*/
461 * label_cmp - label comparison for set ordering
462 * @a: label to compare (NOT NULL)
463 * @b: label to compare (NOT NULL)
465 * Returns: <0 if a < b
469 static int label_cmp(struct aa_label *a, struct aa_label *b)
476 return vec_cmp(a->vec, a->size, b->vec, b->size);
479 /* helper fn for label_for_each_confined */
480 int aa_label_next_confined(struct aa_label *label, int i)
485 for (; i < label->size; i++) {
486 if (!profile_unconfined(label->vec[i]))
494 * aa_label_next_not_in_set - return the next profile of @sub not in @set
496 * @set: label to test against
497 * @sub: label to if is subset of @set
499 * Returns: profile in @sub that is not in @set, with iterator set pos after
500 * else NULL if @sub is a subset of @set
502 struct aa_profile *__aa_label_next_not_in_set(struct label_it *I,
503 struct aa_label *set,
504 struct aa_label *sub)
509 AA_BUG(I->i > set->size);
512 AA_BUG(I->j > sub->size);
514 while (I->j < sub->size && I->i < set->size) {
515 int res = profile_cmp(sub->vec[I->j], set->vec[I->i]);
523 return sub->vec[(I->j)++];
526 if (I->j < sub->size)
527 return sub->vec[(I->j)++];
533 * aa_label_is_subset - test if @sub is a subset of @set
534 * @set: label to test against
535 * @sub: label to test if is subset of @set
537 * Returns: true if @sub is subset of @set
540 bool aa_label_is_subset(struct aa_label *set, struct aa_label *sub)
542 struct label_it i = { };
550 return __aa_label_next_not_in_set(&i, set, sub) == NULL;
556 * __label_remove - remove @label from the label set
557 * @l: label to remove
558 * @new: label to redirect to
560 * Requires: labels_set(@label)->lock write_lock
561 * Returns: true if the label was in the tree and removed
563 static bool __label_remove(struct aa_label *label, struct aa_label *new)
565 struct aa_labelset *ls = labels_set(label);
569 lockdep_assert_held_write(&ls->lock);
572 __aa_proxy_redirect(label, new);
574 if (!label_is_stale(label))
575 __label_make_stale(label);
577 if (label->flags & FLAG_IN_TREE) {
578 rb_erase(&label->node, &ls->root);
579 label->flags &= ~FLAG_IN_TREE;
587 * __label_replace - replace @old with @new in label set
588 * @old: label to remove from label set
589 * @new: label to replace @old with
591 * Requires: labels_set(@old)->lock write_lock
592 * valid ref count be held on @new
593 * Returns: true if @old was in set and replaced by @new
595 * Note: current implementation requires label set be order in such a way
596 * that @new directly replaces @old position in the set (ie.
597 * using pointer comparison of the label address would not work)
599 static bool __label_replace(struct aa_label *old, struct aa_label *new)
601 struct aa_labelset *ls = labels_set(old);
606 lockdep_assert_held_write(&ls->lock);
607 AA_BUG(new->flags & FLAG_IN_TREE);
609 if (!label_is_stale(old))
610 __label_make_stale(old);
612 if (old->flags & FLAG_IN_TREE) {
613 rb_replace_node(&old->node, &new->node, &ls->root);
614 old->flags &= ~FLAG_IN_TREE;
615 new->flags |= FLAG_IN_TREE;
623 * __label_insert - attempt to insert @l into a label set
624 * @ls: set of labels to insert @l into (NOT NULL)
625 * @label: new label to insert (NOT NULL)
626 * @replace: whether insertion should replace existing entry that is not stale
628 * Requires: @ls->lock
629 * caller to hold a valid ref on l
630 * if @replace is true l has a preallocated proxy associated
631 * Returns: @l if successful in inserting @l - with additional refcount
632 * else ref counted equivalent label that is already in the set,
633 * the else condition only happens if @replace is false
635 static struct aa_label *__label_insert(struct aa_labelset *ls,
636 struct aa_label *label, bool replace)
638 struct rb_node **new, *parent = NULL;
642 AA_BUG(labels_set(label) != ls);
643 lockdep_assert_held_write(&ls->lock);
644 AA_BUG(label->flags & FLAG_IN_TREE);
646 /* Figure out where to put new node */
647 new = &ls->root.rb_node;
649 struct aa_label *this = rb_entry(*new, struct aa_label, node);
650 int result = label_cmp(label, this);
654 /* !__aa_get_label means queued for destruction,
655 * so replace in place, however the label has
656 * died before the replacement so do not share
659 if (!replace && !label_is_stale(this)) {
660 if (__aa_get_label(this))
663 __proxy_share(this, label);
664 AA_BUG(!__label_replace(this, label));
665 return aa_get_label(label);
666 } else if (result < 0)
667 new = &((*new)->rb_left);
668 else /* (result > 0) */
669 new = &((*new)->rb_right);
672 /* Add new node and rebalance tree. */
673 rb_link_node(&label->node, parent, new);
674 rb_insert_color(&label->node, &ls->root);
675 label->flags |= FLAG_IN_TREE;
677 return aa_get_label(label);
681 * __vec_find - find label that matches @vec in label set
682 * @vec: vec of profiles to find matching label for (NOT NULL)
685 * Requires: @vec_labelset(vec) lock held
686 * caller to hold a valid ref on l
688 * Returns: ref counted @label if matching label is in tree
689 * ref counted label that is equiv to @l in tree
690 * else NULL if @vec equiv is not in tree
692 static struct aa_label *__vec_find(struct aa_profile **vec, int n)
694 struct rb_node *node;
700 node = vec_labelset(vec, n)->root.rb_node;
702 struct aa_label *this = rb_entry(node, struct aa_label, node);
703 int result = vec_cmp(this->vec, this->size, vec, n);
706 node = node->rb_left;
708 node = node->rb_right;
710 return __aa_get_label(this);
717 * __label_find - find label @label in label set
718 * @label: label to find (NOT NULL)
720 * Requires: labels_set(@label)->lock held
721 * caller to hold a valid ref on l
723 * Returns: ref counted @label if @label is in tree OR
724 * ref counted label that is equiv to @label in tree
725 * else NULL if @label or equiv is not in tree
727 static struct aa_label *__label_find(struct aa_label *label)
731 return __vec_find(label->vec, label->size);
736 * aa_label_remove - remove a label from the labelset
737 * @label: label to remove
739 * Returns: true if @label was removed from the tree
740 * else @label was not in tree so it could not be removed
742 bool aa_label_remove(struct aa_label *label)
744 struct aa_labelset *ls = labels_set(label);
750 write_lock_irqsave(&ls->lock, flags);
751 res = __label_remove(label, ns_unconfined(labels_ns(label)));
752 write_unlock_irqrestore(&ls->lock, flags);
758 * aa_label_replace - replace a label @old with a new version @new
759 * @old: label to replace
760 * @new: label replacing @old
762 * Returns: true if @old was in tree and replaced
763 * else @old was not in tree, and @new was not inserted
765 bool aa_label_replace(struct aa_label *old, struct aa_label *new)
770 if (name_is_shared(old, new) && labels_ns(old) == labels_ns(new)) {
771 write_lock_irqsave(&labels_set(old)->lock, flags);
772 if (old->proxy != new->proxy)
773 __proxy_share(old, new);
775 __aa_proxy_redirect(old, new);
776 res = __label_replace(old, new);
777 write_unlock_irqrestore(&labels_set(old)->lock, flags);
780 struct aa_labelset *ls = labels_set(old);
782 write_lock_irqsave(&ls->lock, flags);
783 res = __label_remove(old, new);
784 if (labels_ns(old) != labels_ns(new)) {
785 write_unlock_irqrestore(&ls->lock, flags);
786 ls = labels_set(new);
787 write_lock_irqsave(&ls->lock, flags);
789 l = __label_insert(ls, new, true);
791 write_unlock_irqrestore(&ls->lock, flags);
799 * vec_find - find label @l in label set
800 * @vec: array of profiles to find equiv label for (NOT NULL)
803 * Returns: refcounted label if @vec equiv is in tree
804 * else NULL if @vec equiv is not in tree
806 static struct aa_label *vec_find(struct aa_profile **vec, int n)
808 struct aa_labelset *ls;
809 struct aa_label *label;
816 ls = vec_labelset(vec, n);
817 read_lock_irqsave(&ls->lock, flags);
818 label = __vec_find(vec, n);
819 read_unlock_irqrestore(&ls->lock, flags);
824 /* requires sort and merge done first */
825 static struct aa_label *vec_create_and_insert_label(struct aa_profile **vec,
828 struct aa_label *label = NULL;
829 struct aa_labelset *ls;
831 struct aa_label *new;
837 return aa_get_label(&vec[0]->label);
839 ls = labels_set(&vec[len - 1]->label);
841 /* TODO: enable when read side is lockless
842 * check if label exists before taking locks
844 new = aa_label_alloc(len, NULL, gfp);
848 for (i = 0; i < len; i++)
849 new->vec[i] = aa_get_profile(vec[i]);
851 write_lock_irqsave(&ls->lock, flags);
852 label = __label_insert(ls, new, false);
853 write_unlock_irqrestore(&ls->lock, flags);
854 label_free_or_put_new(label, new);
859 struct aa_label *aa_vec_find_or_create_label(struct aa_profile **vec, int len,
862 struct aa_label *label = vec_find(vec, len);
867 return vec_create_and_insert_label(vec, len, gfp);
871 * aa_label_find - find label @label in label set
872 * @label: label to find (NOT NULL)
874 * Requires: caller to hold a valid ref on l
876 * Returns: refcounted @label if @label is in tree
877 * refcounted label that is equiv to @label in tree
878 * else NULL if @label or equiv is not in tree
880 struct aa_label *aa_label_find(struct aa_label *label)
884 return vec_find(label->vec, label->size);
889 * aa_label_insert - insert label @label into @ls or return existing label
890 * @ls - labelset to insert @label into
891 * @label - label to insert
893 * Requires: caller to hold a valid ref on @label
895 * Returns: ref counted @label if successful in inserting @label
896 * else ref counted equivalent label that is already in the set
898 struct aa_label *aa_label_insert(struct aa_labelset *ls, struct aa_label *label)
906 /* check if label exists before taking lock */
907 if (!label_is_stale(label)) {
908 read_lock_irqsave(&ls->lock, flags);
909 l = __label_find(label);
910 read_unlock_irqrestore(&ls->lock, flags);
915 write_lock_irqsave(&ls->lock, flags);
916 l = __label_insert(ls, label, false);
917 write_unlock_irqrestore(&ls->lock, flags);
924 * aa_label_next_in_merge - find the next profile when merging @a and @b
929 * Returns: next profile
930 * else null if no more profiles
932 struct aa_profile *aa_label_next_in_merge(struct label_it *I,
940 AA_BUG(I->i > a->size);
942 AA_BUG(I->j > b->size);
944 if (I->i < a->size) {
945 if (I->j < b->size) {
946 int res = profile_cmp(a->vec[I->i], b->vec[I->j]);
949 return b->vec[(I->j)++];
954 return a->vec[(I->i)++];
958 return b->vec[(I->j)++];
964 * label_merge_cmp - cmp of @a merging with @b against @z for set ordering
965 * @a: label to merge then compare (NOT NULL)
966 * @b: label to merge then compare (NOT NULL)
967 * @z: label to compare merge against (NOT NULL)
969 * Assumes: using the most recent versions of @a, @b, and @z
971 * Returns: <0 if a < b
975 static int label_merge_cmp(struct aa_label *a, struct aa_label *b,
978 struct aa_profile *p = NULL;
979 struct label_it i = { };
987 k < z->size && (p = aa_label_next_in_merge(&i, a, b));
989 int res = profile_cmp(p, z->vec[k]);
997 else if (k < z->size)
1003 * label_merge_insert - create a new label by merging @a and @b
1004 * @new: preallocated label to merge into (NOT NULL)
1005 * @a: label to merge with @b (NOT NULL)
1006 * @b: label to merge with @a (NOT NULL)
1008 * Requires: preallocated proxy
1010 * Returns: ref counted label either @new if merge is unique
1011 * @a if @b is a subset of @a
1012 * @b if @a is a subset of @b
1014 * NOTE: will not use @new if the merge results in @new == @a or @b
1016 * Must be used within labelset write lock to avoid racing with
1017 * setting labels stale.
1019 static struct aa_label *label_merge_insert(struct aa_label *new,
1023 struct aa_label *label;
1024 struct aa_labelset *ls;
1025 struct aa_profile *next;
1027 unsigned long flags;
1028 int k = 0, invcount = 0;
1032 AA_BUG(a->size < 0);
1034 AA_BUG(b->size < 0);
1036 AA_BUG(new->size < a->size + b->size);
1038 label_for_each_in_merge(i, a, b, next) {
1040 if (profile_is_stale(next)) {
1041 new->vec[k] = aa_get_newest_profile(next);
1042 AA_BUG(!new->vec[k]->label.proxy);
1043 AA_BUG(!new->vec[k]->label.proxy->label);
1044 if (next->label.proxy != new->vec[k]->label.proxy)
1049 new->vec[k++] = aa_get_profile(next);
1051 /* set to actual size which is <= allocated len */
1056 new->size -= aa_vec_unique(&new->vec[0], new->size,
1057 VEC_FLAG_TERMINATE);
1058 /* TODO: deal with reference labels */
1059 if (new->size == 1) {
1060 label = aa_get_label(&new->vec[0]->label);
1063 } else if (!stale) {
1065 * merge could be same as a || b, note: it is not possible
1066 * for new->size == a->size == b->size unless a == b
1069 return aa_get_label(a);
1070 else if (k == b->size)
1071 return aa_get_label(b);
1073 if (vec_unconfined(new->vec, new->size))
1074 new->flags |= FLAG_UNCONFINED;
1075 ls = labels_set(new);
1076 write_lock_irqsave(&ls->lock, flags);
1077 label = __label_insert(labels_set(new), new, false);
1078 write_unlock_irqrestore(&ls->lock, flags);
1084 * labelset_of_merge - find which labelset a merged label should be inserted
1085 * @a: label to merge and insert
1086 * @b: label to merge and insert
1088 * Returns: labelset that the merged label should be inserted into
1090 static struct aa_labelset *labelset_of_merge(struct aa_label *a,
1093 struct aa_ns *nsa = labels_ns(a);
1094 struct aa_ns *nsb = labels_ns(b);
1096 if (ns_cmp(nsa, nsb) <= 0)
1097 return &nsa->labels;
1098 return &nsb->labels;
1102 * __label_find_merge - find label that is equiv to merge of @a and @b
1103 * @ls: set of labels to search (NOT NULL)
1104 * @a: label to merge with @b (NOT NULL)
1105 * @b: label to merge with @a (NOT NULL)
1107 * Requires: ls->lock read_lock held
1109 * Returns: ref counted label that is equiv to merge of @a and @b
1110 * else NULL if merge of @a and @b is not in set
1112 static struct aa_label *__label_find_merge(struct aa_labelset *ls,
1116 struct rb_node *node;
1123 return __label_find(a);
1125 node = ls->root.rb_node;
1127 struct aa_label *this = container_of(node, struct aa_label,
1129 int result = label_merge_cmp(a, b, this);
1132 node = node->rb_left;
1133 else if (result > 0)
1134 node = node->rb_right;
1136 return __aa_get_label(this);
1144 * aa_label_find_merge - find label that is equiv to merge of @a and @b
1145 * @a: label to merge with @b (NOT NULL)
1146 * @b: label to merge with @a (NOT NULL)
1148 * Requires: labels be fully constructed with a valid ns
1150 * Returns: ref counted label that is equiv to merge of @a and @b
1151 * else NULL if merge of @a and @b is not in set
1153 struct aa_label *aa_label_find_merge(struct aa_label *a, struct aa_label *b)
1155 struct aa_labelset *ls;
1156 struct aa_label *label, *ar = NULL, *br = NULL;
1157 unsigned long flags;
1162 if (label_is_stale(a))
1163 a = ar = aa_get_newest_label(a);
1164 if (label_is_stale(b))
1165 b = br = aa_get_newest_label(b);
1166 ls = labelset_of_merge(a, b);
1167 read_lock_irqsave(&ls->lock, flags);
1168 label = __label_find_merge(ls, a, b);
1169 read_unlock_irqrestore(&ls->lock, flags);
1177 * aa_label_merge - attempt to insert new merged label of @a and @b
1178 * @ls: set of labels to insert label into (NOT NULL)
1179 * @a: label to merge with @b (NOT NULL)
1180 * @b: label to merge with @a (NOT NULL)
1181 * @gfp: memory allocation type
1183 * Requires: caller to hold valid refs on @a and @b
1184 * labels be fully constructed with a valid ns
1186 * Returns: ref counted new label if successful in inserting merge of a & b
1187 * else ref counted equivalent label that is already in the set.
1188 * else NULL if could not create label (-ENOMEM)
1190 struct aa_label *aa_label_merge(struct aa_label *a, struct aa_label *b,
1193 struct aa_label *label = NULL;
1199 return aa_get_newest_label(a);
1201 /* TODO: enable when read side is lockless
1202 * check if label exists before taking locks
1203 if (!label_is_stale(a) && !label_is_stale(b))
1204 label = aa_label_find_merge(a, b);
1208 struct aa_label *new;
1210 a = aa_get_newest_label(a);
1211 b = aa_get_newest_label(b);
1213 /* could use label_merge_len(a, b), but requires double
1214 * comparison for small savings
1216 new = aa_label_alloc(a->size + b->size, NULL, gfp);
1220 label = label_merge_insert(new, a, b);
1221 label_free_or_put_new(label, new);
1230 static inline bool label_is_visible(struct aa_profile *profile,
1231 struct aa_label *label)
1233 return aa_ns_visible(profile->ns, labels_ns(label), true);
1236 /* match a profile and its associated ns component if needed
1237 * Assumes visibility test has already been done.
1238 * If a subns profile is not to be matched should be prescreened with
1241 static inline unsigned int match_component(struct aa_profile *profile,
1242 struct aa_profile *tp,
1245 const char *ns_name;
1247 if (profile->ns == tp->ns)
1248 return aa_dfa_match(profile->policy.dfa, state, tp->base.hname);
1250 /* try matching with namespace name and then profile */
1251 ns_name = aa_ns_name(profile->ns, tp->ns, true);
1252 state = aa_dfa_match_len(profile->policy.dfa, state, ":", 1);
1253 state = aa_dfa_match(profile->policy.dfa, state, ns_name);
1254 state = aa_dfa_match_len(profile->policy.dfa, state, ":", 1);
1255 return aa_dfa_match(profile->policy.dfa, state, tp->base.hname);
1259 * label_compound_match - find perms for full compound label
1260 * @profile: profile to find perms for
1261 * @label: label to check access permissions for
1262 * @start: state to start match in
1263 * @subns: whether to do permission checks on components in a subns
1264 * @request: permissions to request
1265 * @perms: perms struct to set
1267 * Returns: 0 on success else ERROR
1269 * For the label A//&B//&C this does the perm match for A//&B//&C
1270 * @perms should be preinitialized with allperms OR a previous permission
1271 * check to be stacked.
1273 static int label_compound_match(struct aa_profile *profile,
1274 struct aa_label *label,
1275 unsigned int state, bool subns, u32 request,
1276 struct aa_perms *perms)
1278 struct aa_profile *tp;
1281 /* find first subcomponent that is visible */
1282 label_for_each(i, label, tp) {
1283 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1285 state = match_component(profile, tp, state);
1291 /* no component visible */
1296 label_for_each_cont(i, label, tp) {
1297 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1299 state = aa_dfa_match(profile->policy.dfa, state, "//&");
1300 state = match_component(profile, tp, state);
1304 aa_compute_perms(profile->policy.dfa, state, perms);
1305 aa_apply_modes_to_perms(profile, perms);
1306 if ((perms->allow & request) != request)
1317 * label_components_match - find perms for all subcomponents of a label
1318 * @profile: profile to find perms for
1319 * @label: label to check access permissions for
1320 * @start: state to start match in
1321 * @subns: whether to do permission checks on components in a subns
1322 * @request: permissions to request
1323 * @perms: an initialized perms struct to add accumulation to
1325 * Returns: 0 on success else ERROR
1327 * For the label A//&B//&C this does the perm match for each of A and B and C
1328 * @perms should be preinitialized with allperms OR a previous permission
1329 * check to be stacked.
1331 static int label_components_match(struct aa_profile *profile,
1332 struct aa_label *label, unsigned int start,
1333 bool subns, u32 request,
1334 struct aa_perms *perms)
1336 struct aa_profile *tp;
1338 struct aa_perms tmp;
1339 unsigned int state = 0;
1341 /* find first subcomponent to test */
1342 label_for_each(i, label, tp) {
1343 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1345 state = match_component(profile, tp, start);
1351 /* no subcomponents visible - no change in perms */
1355 aa_compute_perms(profile->policy.dfa, state, &tmp);
1356 aa_apply_modes_to_perms(profile, &tmp);
1357 aa_perms_accum(perms, &tmp);
1358 label_for_each_cont(i, label, tp) {
1359 if (!aa_ns_visible(profile->ns, tp->ns, subns))
1361 state = match_component(profile, tp, start);
1364 aa_compute_perms(profile->policy.dfa, state, &tmp);
1365 aa_apply_modes_to_perms(profile, &tmp);
1366 aa_perms_accum(perms, &tmp);
1369 if ((perms->allow & request) != request)
1380 * aa_label_match - do a multi-component label match
1381 * @profile: profile to match against (NOT NULL)
1382 * @label: label to match (NOT NULL)
1383 * @state: state to start in
1384 * @subns: whether to match subns components
1385 * @request: permission request
1386 * @perms: Returns computed perms (NOT NULL)
1388 * Returns: the state the match finished in, may be the none matching state
1390 int aa_label_match(struct aa_profile *profile, struct aa_label *label,
1391 unsigned int state, bool subns, u32 request,
1392 struct aa_perms *perms)
1394 int error = label_compound_match(profile, label, state, subns, request,
1400 return label_components_match(profile, label, state, subns, request,
1406 * aa_update_label_name - update a label to have a stored name
1407 * @ns: ns being viewed from (NOT NULL)
1408 * @label: label to update (NOT NULL)
1409 * @gfp: type of memory allocation
1411 * Requires: labels_set(label) not locked in caller
1413 * note: only updates the label name if it does not have a name already
1414 * and if it is in the labelset
1416 bool aa_update_label_name(struct aa_ns *ns, struct aa_label *label, gfp_t gfp)
1418 struct aa_labelset *ls;
1419 unsigned long flags;
1420 char __counted *name;
1426 if (label->hname || labels_ns(label) != ns)
1429 if (aa_label_acntsxprint(&name, ns, label, FLAGS_NONE, gfp) == -1)
1432 ls = labels_set(label);
1433 write_lock_irqsave(&ls->lock, flags);
1434 if (!label->hname && label->flags & FLAG_IN_TREE) {
1435 label->hname = name;
1439 write_unlock_irqrestore(&ls->lock, flags);
1445 * cached label name is present and visible
1446 * @label->hname only exists if label is namespace hierachical
1448 static inline bool use_label_hname(struct aa_ns *ns, struct aa_label *label,
1451 if (label->hname && (!ns || labels_ns(label) == ns) &&
1452 !(flags & ~FLAG_SHOW_MODE))
1458 /* helper macro for snprint routines */
1459 #define update_for_len(total, len, size, str) \
1463 len = min(len, size); \
1469 * aa_profile_snxprint - print a profile name to a buffer
1470 * @str: buffer to write to. (MAY BE NULL if @size == 0)
1471 * @size: size of buffer
1472 * @view: namespace profile is being viewed from
1473 * @profile: profile to view (NOT NULL)
1474 * @flags: whether to include the mode string
1475 * @prev_ns: last ns printed when used in compound print
1477 * Returns: size of name written or would be written if larger than
1480 * Note: will not print anything if the profile is not visible
1482 static int aa_profile_snxprint(char *str, size_t size, struct aa_ns *view,
1483 struct aa_profile *profile, int flags,
1484 struct aa_ns **prev_ns)
1486 const char *ns_name = NULL;
1488 AA_BUG(!str && size != 0);
1492 view = profiles_ns(profile);
1494 if (view != profile->ns &&
1495 (!prev_ns || (*prev_ns != profile->ns))) {
1497 *prev_ns = profile->ns;
1498 ns_name = aa_ns_name(view, profile->ns,
1499 flags & FLAG_VIEW_SUBNS);
1500 if (ns_name == aa_hidden_ns_name) {
1501 if (flags & FLAG_HIDDEN_UNCONFINED)
1502 return snprintf(str, size, "%s", "unconfined");
1503 return snprintf(str, size, "%s", ns_name);
1507 if ((flags & FLAG_SHOW_MODE) && profile != profile->ns->unconfined) {
1508 const char *modestr = aa_profile_mode_names[profile->mode];
1511 return snprintf(str, size, ":%s:%s (%s)", ns_name,
1512 profile->base.hname, modestr);
1513 return snprintf(str, size, "%s (%s)", profile->base.hname,
1518 return snprintf(str, size, ":%s:%s", ns_name,
1519 profile->base.hname);
1520 return snprintf(str, size, "%s", profile->base.hname);
1523 static const char *label_modename(struct aa_ns *ns, struct aa_label *label,
1526 struct aa_profile *profile;
1528 int mode = -1, count = 0;
1530 label_for_each(i, label, profile) {
1531 if (aa_ns_visible(ns, profile->ns, flags & FLAG_VIEW_SUBNS)) {
1532 if (profile->mode == APPARMOR_UNCONFINED)
1533 /* special case unconfined so stacks with
1534 * unconfined don't report as mixed. ie.
1535 * profile_foo//&:ns1:unconfined (mixed)
1540 mode = profile->mode;
1541 else if (mode != profile->mode)
1549 /* everything was unconfined */
1550 mode = APPARMOR_UNCONFINED;
1552 return aa_profile_mode_names[mode];
1555 /* if any visible label is not unconfined the display_mode returns true */
1556 static inline bool display_mode(struct aa_ns *ns, struct aa_label *label,
1559 if ((flags & FLAG_SHOW_MODE)) {
1560 struct aa_profile *profile;
1563 label_for_each(i, label, profile) {
1564 if (aa_ns_visible(ns, profile->ns,
1565 flags & FLAG_VIEW_SUBNS) &&
1566 profile != profile->ns->unconfined)
1569 /* only ns->unconfined in set of profiles in ns */
1577 * aa_label_snxprint - print a label name to a string buffer
1578 * @str: buffer to write to. (MAY BE NULL if @size == 0)
1579 * @size: size of buffer
1580 * @ns: namespace profile is being viewed from
1581 * @label: label to view (NOT NULL)
1582 * @flags: whether to include the mode string
1584 * Returns: size of name written or would be written if larger than
1587 * Note: labels do not have to be strictly hierarchical to the ns as
1588 * objects may be shared across different namespaces and thus
1589 * pickup labeling from each ns. If a particular part of the
1590 * label is not visible it will just be excluded. And if none
1591 * of the label is visible "---" will be used.
1593 int aa_label_snxprint(char *str, size_t size, struct aa_ns *ns,
1594 struct aa_label *label, int flags)
1596 struct aa_profile *profile;
1597 struct aa_ns *prev_ns = NULL;
1599 int count = 0, total = 0;
1602 AA_BUG(!str && size != 0);
1605 if (flags & FLAG_ABS_ROOT) {
1607 len = snprintf(str, size, "=");
1608 update_for_len(total, len, size, str);
1610 ns = labels_ns(label);
1613 label_for_each(i, label, profile) {
1614 if (aa_ns_visible(ns, profile->ns, flags & FLAG_VIEW_SUBNS)) {
1616 len = snprintf(str, size, "//&");
1617 update_for_len(total, len, size, str);
1619 len = aa_profile_snxprint(str, size, ns, profile,
1620 flags & FLAG_VIEW_SUBNS,
1622 update_for_len(total, len, size, str);
1628 if (flags & FLAG_HIDDEN_UNCONFINED)
1629 return snprintf(str, size, "%s", "unconfined");
1630 return snprintf(str, size, "%s", aa_hidden_ns_name);
1633 /* count == 1 && ... is for backwards compat where the mode
1634 * is not displayed for 'unconfined' in the current ns
1636 if (display_mode(ns, label, flags)) {
1637 len = snprintf(str, size, " (%s)",
1638 label_modename(ns, label, flags));
1639 update_for_len(total, len, size, str);
1644 #undef update_for_len
1647 * aa_label_asxprint - allocate a string buffer and print label into it
1648 * @strp: Returns - the allocated buffer with the label name. (NOT NULL)
1649 * @ns: namespace profile is being viewed from
1650 * @label: label to view (NOT NULL)
1651 * @flags: flags controlling what label info is printed
1652 * @gfp: kernel memory allocation type
1654 * Returns: size of name written or would be written if larger than
1657 int aa_label_asxprint(char **strp, struct aa_ns *ns, struct aa_label *label,
1658 int flags, gfp_t gfp)
1665 size = aa_label_snxprint(NULL, 0, ns, label, flags);
1669 *strp = kmalloc(size + 1, gfp);
1672 return aa_label_snxprint(*strp, size + 1, ns, label, flags);
1676 * aa_label_acntsxprint - allocate a __counted string buffer and print label
1677 * @strp: buffer to write to. (MAY BE NULL if @size == 0)
1678 * @ns: namespace profile is being viewed from
1679 * @label: label to view (NOT NULL)
1680 * @flags: flags controlling what label info is printed
1681 * @gfp: kernel memory allocation type
1683 * Returns: size of name written or would be written if larger than
1686 int aa_label_acntsxprint(char __counted **strp, struct aa_ns *ns,
1687 struct aa_label *label, int flags, gfp_t gfp)
1694 size = aa_label_snxprint(NULL, 0, ns, label, flags);
1698 *strp = aa_str_alloc(size + 1, gfp);
1701 return aa_label_snxprint(*strp, size + 1, ns, label, flags);
1705 void aa_label_xaudit(struct audit_buffer *ab, struct aa_ns *ns,
1706 struct aa_label *label, int flags, gfp_t gfp)
1715 if (!use_label_hname(ns, label, flags) ||
1716 display_mode(ns, label, flags)) {
1717 len = aa_label_asxprint(&name, ns, label, flags, gfp);
1719 AA_DEBUG("label print error");
1724 str = (char *) label->hname;
1727 if (audit_string_contains_control(str, len))
1728 audit_log_n_hex(ab, str, len);
1730 audit_log_n_string(ab, str, len);
1735 void aa_label_seq_xprint(struct seq_file *f, struct aa_ns *ns,
1736 struct aa_label *label, int flags, gfp_t gfp)
1741 if (!use_label_hname(ns, label, flags)) {
1745 len = aa_label_asxprint(&str, ns, label, flags, gfp);
1747 AA_DEBUG("label print error");
1750 seq_printf(f, "%s", str);
1752 } else if (display_mode(ns, label, flags))
1753 seq_printf(f, "%s (%s)", label->hname,
1754 label_modename(ns, label, flags));
1756 seq_printf(f, "%s", label->hname);
1759 void aa_label_xprintk(struct aa_ns *ns, struct aa_label *label, int flags,
1764 if (!use_label_hname(ns, label, flags)) {
1768 len = aa_label_asxprint(&str, ns, label, flags, gfp);
1770 AA_DEBUG("label print error");
1775 } else if (display_mode(ns, label, flags))
1776 pr_info("%s (%s)", label->hname,
1777 label_modename(ns, label, flags));
1779 pr_info("%s", label->hname);
1782 void aa_label_audit(struct audit_buffer *ab, struct aa_label *label, gfp_t gfp)
1784 struct aa_ns *ns = aa_get_current_ns();
1786 aa_label_xaudit(ab, ns, label, FLAG_VIEW_SUBNS, gfp);
1790 void aa_label_seq_print(struct seq_file *f, struct aa_label *label, gfp_t gfp)
1792 struct aa_ns *ns = aa_get_current_ns();
1794 aa_label_seq_xprint(f, ns, label, FLAG_VIEW_SUBNS, gfp);
1798 void aa_label_printk(struct aa_label *label, gfp_t gfp)
1800 struct aa_ns *ns = aa_get_current_ns();
1802 aa_label_xprintk(ns, label, FLAG_VIEW_SUBNS, gfp);
1806 static int label_count_strn_entries(const char *str, size_t n)
1808 const char *end = str + n;
1814 for (split = aa_label_strn_split(str, end - str);
1816 split = aa_label_strn_split(str, end - str)) {
1825 * ensure stacks with components like
1827 * have :ns: applied to both 'A' and 'B' by making the lookup relative
1828 * to the base if the lookup specifies an ns, else making the stacked lookup
1829 * relative to the last embedded ns in the string.
1831 static struct aa_profile *fqlookupn_profile(struct aa_label *base,
1832 struct aa_label *currentbase,
1833 const char *str, size_t n)
1835 const char *first = skipn_spaces(str, n);
1837 if (first && *first == ':')
1838 return aa_fqlookupn_profile(base, str, n);
1840 return aa_fqlookupn_profile(currentbase, str, n);
1844 * aa_label_strn_parse - parse, validate and convert a text string to a label
1845 * @base: base label to use for lookups (NOT NULL)
1846 * @str: null terminated text string (NOT NULL)
1847 * @n: length of str to parse, will stop at \0 if encountered before n
1848 * @gfp: allocation type
1849 * @create: true if should create compound labels if they don't exist
1850 * @force_stack: true if should stack even if no leading &
1852 * Returns: the matching refcounted label if present
1855 struct aa_label *aa_label_strn_parse(struct aa_label *base, const char *str,
1856 size_t n, gfp_t gfp, bool create,
1859 DEFINE_VEC(profile, vec);
1860 struct aa_label *label, *currbase = base;
1861 int i, len, stack = 0, error;
1862 const char *end = str + n;
1868 str = skipn_spaces(str, n);
1869 if (str == NULL || (*str == '=' && base != &root_ns->unconfined->label))
1870 return ERR_PTR(-EINVAL);
1872 len = label_count_strn_entries(str, end - str);
1873 if (*str == '&' || force_stack) {
1874 /* stack on top of base */
1881 error = vec_setup(profile, vec, len, gfp);
1883 return ERR_PTR(error);
1885 for (i = 0; i < stack; i++)
1886 vec[i] = aa_get_profile(base->vec[i]);
1888 for (split = aa_label_strn_split(str, end - str), i = stack;
1889 split && i < len; i++) {
1890 vec[i] = fqlookupn_profile(base, currbase, str, split - str);
1894 * if component specified a new ns it becomes the new base
1895 * so that subsequent lookups are relative to it
1897 if (vec[i]->ns != labels_ns(currbase))
1898 currbase = &vec[i]->label;
1900 split = aa_label_strn_split(str, end - str);
1902 /* last element doesn't have a split */
1904 vec[i] = fqlookupn_profile(base, currbase, str, end - str);
1909 /* no need to free vec as len < LOCAL_VEC_ENTRIES */
1910 return &vec[0]->label;
1912 len -= aa_vec_unique(vec, len, VEC_FLAG_TERMINATE);
1913 /* TODO: deal with reference labels */
1915 label = aa_get_label(&vec[0]->label);
1920 label = aa_vec_find_or_create_label(vec, len, gfp);
1922 label = vec_find(vec, len);
1927 /* use adjusted len from after vec_unique, not original */
1928 vec_cleanup(profile, vec, len);
1932 label = ERR_PTR(-ENOENT);
1936 struct aa_label *aa_label_parse(struct aa_label *base, const char *str,
1937 gfp_t gfp, bool create, bool force_stack)
1939 return aa_label_strn_parse(base, str, strlen(str), gfp, create,
1944 * aa_labelset_destroy - remove all labels from the label set
1945 * @ls: label set to cleanup (NOT NULL)
1947 * Labels that are removed from the set may still exist beyond the set
1948 * being destroyed depending on their reference counting
1950 void aa_labelset_destroy(struct aa_labelset *ls)
1952 struct rb_node *node;
1953 unsigned long flags;
1957 write_lock_irqsave(&ls->lock, flags);
1958 for (node = rb_first(&ls->root); node; node = rb_first(&ls->root)) {
1959 struct aa_label *this = rb_entry(node, struct aa_label, node);
1961 if (labels_ns(this) != root_ns)
1962 __label_remove(this,
1963 ns_unconfined(labels_ns(this)->parent));
1965 __label_remove(this, NULL);
1967 write_unlock_irqrestore(&ls->lock, flags);
1971 * @ls: labelset to init (NOT NULL)
1973 void aa_labelset_init(struct aa_labelset *ls)
1977 rwlock_init(&ls->lock);
1981 static struct aa_label *labelset_next_stale(struct aa_labelset *ls)
1983 struct aa_label *label;
1984 struct rb_node *node;
1985 unsigned long flags;
1989 read_lock_irqsave(&ls->lock, flags);
1991 __labelset_for_each(ls, node) {
1992 label = rb_entry(node, struct aa_label, node);
1993 if ((label_is_stale(label) ||
1994 vec_is_stale(label->vec, label->size)) &&
1995 __aa_get_label(label))
2002 read_unlock_irqrestore(&ls->lock, flags);
2008 * __label_update - insert updated version of @label into labelset
2009 * @label - the label to update/replace
2011 * Returns: new label that is up to date
2012 * else NULL on failure
2014 * Requires: @ns lock be held
2016 * Note: worst case is the stale @label does not get updated and has
2017 * to be updated at a later time.
2019 static struct aa_label *__label_update(struct aa_label *label)
2021 struct aa_label *new, *tmp;
2022 struct aa_labelset *ls;
2023 unsigned long flags;
2024 int i, invcount = 0;
2027 AA_BUG(!mutex_is_locked(&labels_ns(label)->lock));
2029 new = aa_label_alloc(label->size, label->proxy, GFP_KERNEL);
2034 * while holding the ns_lock will stop profile replacement, removal,
2035 * and label updates, label merging and removal can be occurring
2037 ls = labels_set(label);
2038 write_lock_irqsave(&ls->lock, flags);
2039 for (i = 0; i < label->size; i++) {
2040 AA_BUG(!label->vec[i]);
2041 new->vec[i] = aa_get_newest_profile(label->vec[i]);
2042 AA_BUG(!new->vec[i]);
2043 AA_BUG(!new->vec[i]->label.proxy);
2044 AA_BUG(!new->vec[i]->label.proxy->label);
2045 if (new->vec[i]->label.proxy != label->vec[i]->label.proxy)
2049 /* updated stale label by being removed/renamed from labelset */
2051 new->size -= aa_vec_unique(&new->vec[0], new->size,
2052 VEC_FLAG_TERMINATE);
2053 /* TODO: deal with reference labels */
2054 if (new->size == 1) {
2055 tmp = aa_get_label(&new->vec[0]->label);
2056 AA_BUG(tmp == label);
2059 if (labels_set(label) != labels_set(new)) {
2060 write_unlock_irqrestore(&ls->lock, flags);
2061 tmp = aa_label_insert(labels_set(new), new);
2062 write_lock_irqsave(&ls->lock, flags);
2066 AA_BUG(labels_ns(label) != labels_ns(new));
2068 tmp = __label_insert(labels_set(label), new, true);
2070 /* ensure label is removed, and redirected correctly */
2071 __label_remove(label, tmp);
2072 write_unlock_irqrestore(&ls->lock, flags);
2073 label_free_or_put_new(tmp, new);
2079 * __labelset_update - update labels in @ns
2080 * @ns: namespace to update labels in (NOT NULL)
2082 * Requires: @ns lock be held
2084 * Walk the labelset ensuring that all labels are up to date and valid
2085 * Any label that has a stale component is marked stale and replaced and
2086 * by an updated version.
2088 * If failures happen due to memory pressures then stale labels will
2089 * be left in place until the next pass.
2091 static void __labelset_update(struct aa_ns *ns)
2093 struct aa_label *label;
2096 AA_BUG(!mutex_is_locked(&ns->lock));
2099 label = labelset_next_stale(&ns->labels);
2101 struct aa_label *l = __label_update(label);
2104 aa_put_label(label);
2110 * __aa_labelset_udate_subtree - update all labels with a stale component
2111 * @ns: ns to start update at (NOT NULL)
2113 * Requires: @ns lock be held
2115 * Invalidates labels based on @p in @ns and any children namespaces.
2117 void __aa_labelset_update_subtree(struct aa_ns *ns)
2119 struct aa_ns *child;
2122 AA_BUG(!mutex_is_locked(&ns->lock));
2124 __labelset_update(ns);
2126 list_for_each_entry(child, &ns->sub_ns, base.list) {
2127 mutex_lock_nested(&child->lock, child->level);
2128 __aa_labelset_update_subtree(child);
2129 mutex_unlock(&child->lock);