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kernel/audit_tree.c
21.7 KB
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#include "audit.h" |
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#include <linux/fsnotify_backend.h> |
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#include <linux/namei.h> #include <linux/mount.h> |
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#include <linux/kthread.h> |
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#include <linux/slab.h> |
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struct audit_tree; struct audit_chunk; struct audit_tree { atomic_t count; int goner; struct audit_chunk *root; struct list_head chunks; struct list_head rules; struct list_head list; struct list_head same_root; struct rcu_head head; char pathname[]; }; struct audit_chunk { struct list_head hash; |
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struct fsnotify_mark mark; |
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struct list_head trees; /* with root here */ int dead; int count; |
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atomic_long_t refs; |
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struct rcu_head head; struct node { struct list_head list; struct audit_tree *owner; unsigned index; /* index; upper bit indicates 'will prune' */ } owners[]; }; static LIST_HEAD(tree_list); static LIST_HEAD(prune_list); /* * One struct chunk is attached to each inode of interest. * We replace struct chunk on tagging/untagging. * Rules have pointer to struct audit_tree. * Rules have struct list_head rlist forming a list of rules over * the same tree. * References to struct chunk are collected at audit_inode{,_child}() * time and used in AUDIT_TREE rule matching. * These references are dropped at the same time we are calling * audit_free_names(), etc. * * Cyclic lists galore: * tree.chunks anchors chunk.owners[].list hash_lock * tree.rules anchors rule.rlist audit_filter_mutex * chunk.trees anchors tree.same_root hash_lock * chunk.hash is a hash with middle bits of watch.inode as * a hash function. RCU, hash_lock * * tree is refcounted; one reference for "some rules on rules_list refer to * it", one for each chunk with pointer to it. * |
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* chunk is refcounted by embedded fsnotify_mark + .refs (non-zero refcount |
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* of watch contributes 1 to .refs). |
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* * node.index allows to get from node.list to containing chunk. * MSB of that sucker is stolen to mark taggings that we might have to * revert - several operations have very unpleasant cleanup logics and * that makes a difference. Some. */ |
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static struct fsnotify_group *audit_tree_group; |
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static struct audit_tree *alloc_tree(const char *s) { struct audit_tree *tree; tree = kmalloc(sizeof(struct audit_tree) + strlen(s) + 1, GFP_KERNEL); if (tree) { atomic_set(&tree->count, 1); tree->goner = 0; INIT_LIST_HEAD(&tree->chunks); INIT_LIST_HEAD(&tree->rules); INIT_LIST_HEAD(&tree->list); INIT_LIST_HEAD(&tree->same_root); tree->root = NULL; strcpy(tree->pathname, s); } return tree; } static inline void get_tree(struct audit_tree *tree) { atomic_inc(&tree->count); } |
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static inline void put_tree(struct audit_tree *tree) { if (atomic_dec_and_test(&tree->count)) |
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kfree_rcu(tree, head); |
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} /* to avoid bringing the entire thing in audit.h */ const char *audit_tree_path(struct audit_tree *tree) { return tree->pathname; } |
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static void free_chunk(struct audit_chunk *chunk) |
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{ |
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int i; for (i = 0; i < chunk->count; i++) { if (chunk->owners[i].owner) put_tree(chunk->owners[i].owner); } kfree(chunk); } |
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void audit_put_chunk(struct audit_chunk *chunk) |
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{ |
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if (atomic_long_dec_and_test(&chunk->refs)) free_chunk(chunk); |
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} |
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static void __put_chunk(struct rcu_head *rcu) |
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{ |
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struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head); audit_put_chunk(chunk); |
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} |
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static void audit_tree_destroy_watch(struct fsnotify_mark *entry) |
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{ struct audit_chunk *chunk = container_of(entry, struct audit_chunk, mark); call_rcu(&chunk->head, __put_chunk); } static struct audit_chunk *alloc_chunk(int count) { struct audit_chunk *chunk; size_t size; int i; size = offsetof(struct audit_chunk, owners) + count * sizeof(struct node); chunk = kzalloc(size, GFP_KERNEL); if (!chunk) return NULL; INIT_LIST_HEAD(&chunk->hash); INIT_LIST_HEAD(&chunk->trees); chunk->count = count; atomic_long_set(&chunk->refs, 1); for (i = 0; i < count; i++) { INIT_LIST_HEAD(&chunk->owners[i].list); chunk->owners[i].index = i; } fsnotify_init_mark(&chunk->mark, audit_tree_destroy_watch); return chunk; } |
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enum {HASH_SIZE = 128}; static struct list_head chunk_hash_heads[HASH_SIZE]; static __cacheline_aligned_in_smp DEFINE_SPINLOCK(hash_lock); static inline struct list_head *chunk_hash(const struct inode *inode) { unsigned long n = (unsigned long)inode / L1_CACHE_BYTES; return chunk_hash_heads + n % HASH_SIZE; } |
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/* hash_lock & entry->lock is held by caller */ |
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static void insert_hash(struct audit_chunk *chunk) { |
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struct fsnotify_mark *entry = &chunk->mark; |
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struct list_head *list; |
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if (!entry->i.inode) |
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return; |
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list = chunk_hash(entry->i.inode); |
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list_add_rcu(&chunk->hash, list); } /* called under rcu_read_lock */ struct audit_chunk *audit_tree_lookup(const struct inode *inode) { struct list_head *list = chunk_hash(inode); |
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struct audit_chunk *p; |
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list_for_each_entry_rcu(p, list, hash) { |
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/* mark.inode may have gone NULL, but who cares? */ |
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if (p->mark.i.inode == inode) { |
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atomic_long_inc(&p->refs); |
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return p; } } return NULL; } int audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree) { int n; for (n = 0; n < chunk->count; n++) if (chunk->owners[n].owner == tree) return 1; return 0; } /* tagging and untagging inodes with trees */ |
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static struct audit_chunk *find_chunk(struct node *p) { int index = p->index & ~(1U<<31); p -= index; return container_of(p, struct audit_chunk, owners[0]); } static void untag_chunk(struct node *p) |
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{ |
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struct audit_chunk *chunk = find_chunk(p); |
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struct fsnotify_mark *entry = &chunk->mark; |
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struct audit_chunk *new = NULL; |
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struct audit_tree *owner; int size = chunk->count - 1; int i, j; |
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fsnotify_get_mark(entry); |
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spin_unlock(&hash_lock); |
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if (size) new = alloc_chunk(size); |
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spin_lock(&entry->lock); |
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if (chunk->dead || !entry->i.inode) { |
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spin_unlock(&entry->lock); |
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if (new) free_chunk(new); |
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goto out; |
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} owner = p->owner; if (!size) { chunk->dead = 1; spin_lock(&hash_lock); list_del_init(&chunk->trees); if (owner->root == chunk) owner->root = NULL; list_del_init(&p->list); list_del_rcu(&chunk->hash); spin_unlock(&hash_lock); |
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spin_unlock(&entry->lock); |
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fsnotify_destroy_mark(entry); |
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fsnotify_put_mark(entry); |
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goto out; |
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} |
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if (!new) goto Fallback; |
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fsnotify_duplicate_mark(&new->mark, entry); |
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if (fsnotify_add_mark(&new->mark, new->mark.group, new->mark.i.inode, NULL, 1)) { |
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free_chunk(new); goto Fallback; } chunk->dead = 1; spin_lock(&hash_lock); list_replace_init(&chunk->trees, &new->trees); if (owner->root == chunk) { list_del_init(&owner->same_root); owner->root = NULL; } |
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for (i = j = 0; j <= size; i++, j++) { |
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struct audit_tree *s; if (&chunk->owners[j] == p) { list_del_init(&p->list); i--; continue; } s = chunk->owners[j].owner; new->owners[i].owner = s; new->owners[i].index = chunk->owners[j].index - j + i; if (!s) /* result of earlier fallback */ continue; get_tree(s); |
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list_replace_init(&chunk->owners[j].list, &new->owners[i].list); |
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} list_replace_rcu(&chunk->hash, &new->hash); list_for_each_entry(owner, &new->trees, same_root) owner->root = new; spin_unlock(&hash_lock); |
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spin_unlock(&entry->lock); |
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fsnotify_destroy_mark(entry); |
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fsnotify_put_mark(entry); |
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goto out; |
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Fallback: // do the best we can spin_lock(&hash_lock); if (owner->root == chunk) { list_del_init(&owner->same_root); owner->root = NULL; } list_del_init(&p->list); p->owner = NULL; put_tree(owner); spin_unlock(&hash_lock); |
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spin_unlock(&entry->lock); |
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out: |
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fsnotify_put_mark(entry); |
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spin_lock(&hash_lock); |
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} static int create_chunk(struct inode *inode, struct audit_tree *tree) { |
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struct fsnotify_mark *entry; |
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struct audit_chunk *chunk = alloc_chunk(1); if (!chunk) return -ENOMEM; |
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entry = &chunk->mark; |
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if (fsnotify_add_mark(entry, audit_tree_group, inode, NULL, 0)) { |
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free_chunk(chunk); return -ENOSPC; } |
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spin_lock(&entry->lock); |
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spin_lock(&hash_lock); if (tree->goner) { spin_unlock(&hash_lock); chunk->dead = 1; |
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spin_unlock(&entry->lock); |
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fsnotify_destroy_mark(entry); |
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fsnotify_put_mark(entry); |
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return 0; } chunk->owners[0].index = (1U << 31); chunk->owners[0].owner = tree; get_tree(tree); list_add(&chunk->owners[0].list, &tree->chunks); if (!tree->root) { tree->root = chunk; list_add(&tree->same_root, &chunk->trees); } insert_hash(chunk); spin_unlock(&hash_lock); |
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spin_unlock(&entry->lock); |
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return 0; } /* the first tagged inode becomes root of tree */ static int tag_chunk(struct inode *inode, struct audit_tree *tree) { |
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struct fsnotify_mark *old_entry, *chunk_entry; |
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struct audit_tree *owner; struct audit_chunk *chunk, *old; struct node *p; int n; |
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old_entry = fsnotify_find_inode_mark(audit_tree_group, inode); |
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if (!old_entry) |
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return create_chunk(inode, tree); |
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old = container_of(old_entry, struct audit_chunk, mark); |
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/* are we already there? */ spin_lock(&hash_lock); for (n = 0; n < old->count; n++) { if (old->owners[n].owner == tree) { spin_unlock(&hash_lock); |
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fsnotify_put_mark(old_entry); |
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return 0; } } spin_unlock(&hash_lock); chunk = alloc_chunk(old->count + 1); |
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if (!chunk) { |
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fsnotify_put_mark(old_entry); |
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return -ENOMEM; |
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} |
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chunk_entry = &chunk->mark; spin_lock(&old_entry->lock); |
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if (!old_entry->i.inode) { |
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/* old_entry is being shot, lets just lie */ spin_unlock(&old_entry->lock); fsnotify_put_mark(old_entry); |
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free_chunk(chunk); |
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return -ENOENT; } fsnotify_duplicate_mark(chunk_entry, old_entry); |
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if (fsnotify_add_mark(chunk_entry, chunk_entry->group, chunk_entry->i.inode, NULL, 1)) { |
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spin_unlock(&old_entry->lock); free_chunk(chunk); fsnotify_put_mark(old_entry); |
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return -ENOSPC; } |
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/* even though we hold old_entry->lock, this is safe since chunk_entry->lock could NEVER have been grabbed before */ spin_lock(&chunk_entry->lock); |
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spin_lock(&hash_lock); |
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/* we now hold old_entry->lock, chunk_entry->lock, and hash_lock */ |
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if (tree->goner) { spin_unlock(&hash_lock); chunk->dead = 1; |
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spin_unlock(&chunk_entry->lock); spin_unlock(&old_entry->lock); |
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fsnotify_destroy_mark(chunk_entry); |
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fsnotify_put_mark(chunk_entry); fsnotify_put_mark(old_entry); |
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return 0; } list_replace_init(&old->trees, &chunk->trees); for (n = 0, p = chunk->owners; n < old->count; n++, p++) { struct audit_tree *s = old->owners[n].owner; p->owner = s; p->index = old->owners[n].index; if (!s) /* result of fallback in untag */ continue; get_tree(s); list_replace_init(&old->owners[n].list, &p->list); } p->index = (chunk->count - 1) | (1U<<31); p->owner = tree; get_tree(tree); list_add(&p->list, &tree->chunks); list_replace_rcu(&old->hash, &chunk->hash); list_for_each_entry(owner, &chunk->trees, same_root) owner->root = chunk; old->dead = 1; if (!tree->root) { tree->root = chunk; list_add(&tree->same_root, &chunk->trees); } spin_unlock(&hash_lock); |
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spin_unlock(&chunk_entry->lock); spin_unlock(&old_entry->lock); |
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fsnotify_destroy_mark(old_entry); |
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fsnotify_put_mark(old_entry); /* pair to fsnotify_find mark_entry */ fsnotify_put_mark(old_entry); /* and kill it */ |
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return 0; } |
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static void kill_rules(struct audit_tree *tree) { struct audit_krule *rule, *next; struct audit_entry *entry; struct audit_buffer *ab; list_for_each_entry_safe(rule, next, &tree->rules, rlist) { entry = container_of(rule, struct audit_entry, rule); list_del_init(&rule->rlist); if (rule->tree) { /* not a half-baked one */ ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); |
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audit_log_format(ab, "op="); audit_log_string(ab, "remove rule"); audit_log_format(ab, " dir="); |
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audit_log_untrustedstring(ab, rule->tree->pathname); |
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audit_log_key(ab, rule->filterkey); |
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audit_log_format(ab, " list=%d res=1", rule->listnr); audit_log_end(ab); rule->tree = NULL; list_del_rcu(&entry->list); |
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list_del(&entry->rule.list); |
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call_rcu(&entry->rcu, audit_free_rule_rcu); } } } /* * finish killing struct audit_tree */ static void prune_one(struct audit_tree *victim) { spin_lock(&hash_lock); while (!list_empty(&victim->chunks)) { struct node *p; |
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p = list_entry(victim->chunks.next, struct node, list); |
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untag_chunk(p); |
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} spin_unlock(&hash_lock); put_tree(victim); } /* trim the uncommitted chunks from tree */ static void trim_marked(struct audit_tree *tree) { struct list_head *p, *q; spin_lock(&hash_lock); if (tree->goner) { spin_unlock(&hash_lock); return; } /* reorder */ for (p = tree->chunks.next; p != &tree->chunks; p = q) { struct node *node = list_entry(p, struct node, list); q = p->next; if (node->index & (1U<<31)) { list_del_init(p); list_add(p, &tree->chunks); } } while (!list_empty(&tree->chunks)) { struct node *node; |
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node = list_entry(tree->chunks.next, struct node, list); /* have we run out of marked? */ if (!(node->index & (1U<<31))) break; |
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untag_chunk(node); |
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} if (!tree->root && !tree->goner) { tree->goner = 1; spin_unlock(&hash_lock); mutex_lock(&audit_filter_mutex); kill_rules(tree); list_del_init(&tree->list); mutex_unlock(&audit_filter_mutex); prune_one(tree); } else { spin_unlock(&hash_lock); } } |
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static void audit_schedule_prune(void); |
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/* called with audit_filter_mutex */ int audit_remove_tree_rule(struct audit_krule *rule) { struct audit_tree *tree; tree = rule->tree; if (tree) { spin_lock(&hash_lock); list_del_init(&rule->rlist); if (list_empty(&tree->rules) && !tree->goner) { tree->root = NULL; list_del_init(&tree->same_root); tree->goner = 1; list_move(&tree->list, &prune_list); rule->tree = NULL; spin_unlock(&hash_lock); audit_schedule_prune(); return 1; } rule->tree = NULL; spin_unlock(&hash_lock); return 1; } return 0; } |
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static int compare_root(struct vfsmount *mnt, void *arg) { return mnt->mnt_root->d_inode == arg; } |
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void audit_trim_trees(void) { struct list_head cursor; mutex_lock(&audit_filter_mutex); list_add(&cursor, &tree_list); while (cursor.next != &tree_list) { struct audit_tree *tree; |
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struct path path; |
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struct vfsmount *root_mnt; struct node *node; |
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int err; tree = container_of(cursor.next, struct audit_tree, list); get_tree(tree); list_del(&cursor); list_add(&cursor, &tree->list); mutex_unlock(&audit_filter_mutex); |
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err = kern_path(tree->pathname, 0, &path); |
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if (err) goto skip_it; |
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root_mnt = collect_mounts(&path); |
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path_put(&path); |
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if (!root_mnt) goto skip_it; |
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spin_lock(&hash_lock); list_for_each_entry(node, &tree->chunks, list) { |
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struct audit_chunk *chunk = find_chunk(node); |
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/* this could be NULL if the watch is dying else where... */ |
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struct inode *inode = chunk->mark.i.inode; |
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node->index |= 1U<<31; |
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if (iterate_mounts(compare_root, inode, root_mnt)) node->index &= ~(1U<<31); |
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} spin_unlock(&hash_lock); trim_marked(tree); put_tree(tree); |
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drop_collected_mounts(root_mnt); skip_it: mutex_lock(&audit_filter_mutex); } list_del(&cursor); mutex_unlock(&audit_filter_mutex); } |
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int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op) { if (pathname[0] != '/' || rule->listnr != AUDIT_FILTER_EXIT || |
5af75d8d5
|
596 |
op != Audit_equal || |
74c3cbe33
|
597 598 599 600 601 602 603 604 605 606 607 608 |
rule->inode_f || rule->watch || rule->tree) return -EINVAL; rule->tree = alloc_tree(pathname); if (!rule->tree) return -ENOMEM; return 0; } void audit_put_tree(struct audit_tree *tree) { put_tree(tree); } |
1f707137b
|
609 610 611 612 |
static int tag_mount(struct vfsmount *mnt, void *arg) { return tag_chunk(mnt->mnt_root->d_inode, arg); } |
74c3cbe33
|
613 614 615 616 |
/* called with audit_filter_mutex */ int audit_add_tree_rule(struct audit_krule *rule) { struct audit_tree *seed = rule->tree, *tree; |
98bc993f9
|
617 |
struct path path; |
1f707137b
|
618 |
struct vfsmount *mnt; |
74c3cbe33
|
619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 |
int err; list_for_each_entry(tree, &tree_list, list) { if (!strcmp(seed->pathname, tree->pathname)) { put_tree(seed); rule->tree = tree; list_add(&rule->rlist, &tree->rules); return 0; } } tree = seed; list_add(&tree->list, &tree_list); list_add(&rule->rlist, &tree->rules); /* do not set rule->tree yet */ mutex_unlock(&audit_filter_mutex); |
98bc993f9
|
634 |
err = kern_path(tree->pathname, 0, &path); |
74c3cbe33
|
635 636 |
if (err) goto Err; |
589ff870e
|
637 |
mnt = collect_mounts(&path); |
98bc993f9
|
638 |
path_put(&path); |
74c3cbe33
|
639 640 641 642 |
if (!mnt) { err = -ENOMEM; goto Err; } |
74c3cbe33
|
643 644 |
get_tree(tree); |
1f707137b
|
645 |
err = iterate_mounts(tag_mount, tree, mnt); |
74c3cbe33
|
646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 |
drop_collected_mounts(mnt); if (!err) { struct node *node; spin_lock(&hash_lock); list_for_each_entry(node, &tree->chunks, list) node->index &= ~(1U<<31); spin_unlock(&hash_lock); } else { trim_marked(tree); goto Err; } mutex_lock(&audit_filter_mutex); if (list_empty(&rule->rlist)) { put_tree(tree); return -ENOENT; } rule->tree = tree; put_tree(tree); return 0; Err: mutex_lock(&audit_filter_mutex); list_del_init(&tree->list); list_del_init(&tree->rules); put_tree(tree); return err; } int audit_tag_tree(char *old, char *new) { struct list_head cursor, barrier; int failed = 0; |
2096f759a
|
680 |
struct path path1, path2; |
74c3cbe33
|
681 |
struct vfsmount *tagged; |
74c3cbe33
|
682 |
int err; |
2096f759a
|
683 |
err = kern_path(new, 0, &path2); |
74c3cbe33
|
684 685 |
if (err) return err; |
2096f759a
|
686 687 |
tagged = collect_mounts(&path2); path_put(&path2); |
74c3cbe33
|
688 689 |
if (!tagged) return -ENOMEM; |
2096f759a
|
690 |
err = kern_path(old, 0, &path1); |
74c3cbe33
|
691 692 693 694 |
if (err) { drop_collected_mounts(tagged); return err; } |
74c3cbe33
|
695 |
|
74c3cbe33
|
696 697 698 699 700 701 |
mutex_lock(&audit_filter_mutex); list_add(&barrier, &tree_list); list_add(&cursor, &barrier); while (cursor.next != &tree_list) { struct audit_tree *tree; |
2096f759a
|
702 |
int good_one = 0; |
74c3cbe33
|
703 704 705 706 707 708 |
tree = container_of(cursor.next, struct audit_tree, list); get_tree(tree); list_del(&cursor); list_add(&cursor, &tree->list); mutex_unlock(&audit_filter_mutex); |
2096f759a
|
709 710 711 712 |
err = kern_path(tree->pathname, 0, &path2); if (!err) { good_one = path_is_under(&path1, &path2); path_put(&path2); |
74c3cbe33
|
713 |
} |
2096f759a
|
714 |
if (!good_one) { |
74c3cbe33
|
715 716 717 718 |
put_tree(tree); mutex_lock(&audit_filter_mutex); continue; } |
74c3cbe33
|
719 |
|
1f707137b
|
720 |
failed = iterate_mounts(tag_mount, tree, tagged); |
74c3cbe33
|
721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 |
if (failed) { put_tree(tree); mutex_lock(&audit_filter_mutex); break; } mutex_lock(&audit_filter_mutex); spin_lock(&hash_lock); if (!tree->goner) { list_del(&tree->list); list_add(&tree->list, &tree_list); } spin_unlock(&hash_lock); put_tree(tree); } while (barrier.prev != &tree_list) { struct audit_tree *tree; tree = container_of(barrier.prev, struct audit_tree, list); get_tree(tree); list_del(&tree->list); list_add(&tree->list, &barrier); mutex_unlock(&audit_filter_mutex); if (!failed) { struct node *node; spin_lock(&hash_lock); list_for_each_entry(node, &tree->chunks, list) node->index &= ~(1U<<31); spin_unlock(&hash_lock); } else { trim_marked(tree); } put_tree(tree); mutex_lock(&audit_filter_mutex); } list_del(&barrier); list_del(&cursor); |
74c3cbe33
|
761 |
mutex_unlock(&audit_filter_mutex); |
2096f759a
|
762 |
path_put(&path1); |
74c3cbe33
|
763 764 765 766 767 768 |
drop_collected_mounts(tagged); return failed; } /* * That gets run when evict_chunk() ends up needing to kill audit_tree. |
916d75761
|
769 |
* Runs from a separate thread. |
74c3cbe33
|
770 |
*/ |
916d75761
|
771 |
static int prune_tree_thread(void *unused) |
74c3cbe33
|
772 |
{ |
916d75761
|
773 |
mutex_lock(&audit_cmd_mutex); |
74c3cbe33
|
774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 |
mutex_lock(&audit_filter_mutex); while (!list_empty(&prune_list)) { struct audit_tree *victim; victim = list_entry(prune_list.next, struct audit_tree, list); list_del_init(&victim->list); mutex_unlock(&audit_filter_mutex); prune_one(victim); mutex_lock(&audit_filter_mutex); } mutex_unlock(&audit_filter_mutex); |
916d75761
|
790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 |
mutex_unlock(&audit_cmd_mutex); return 0; } static void audit_schedule_prune(void) { kthread_run(prune_tree_thread, NULL, "audit_prune_tree"); } /* * ... and that one is done if evict_chunk() decides to delay until the end * of syscall. Runs synchronously. */ void audit_kill_trees(struct list_head *list) { mutex_lock(&audit_cmd_mutex); mutex_lock(&audit_filter_mutex); while (!list_empty(list)) { struct audit_tree *victim; victim = list_entry(list->next, struct audit_tree, list); kill_rules(victim); list_del_init(&victim->list); mutex_unlock(&audit_filter_mutex); prune_one(victim); mutex_lock(&audit_filter_mutex); } mutex_unlock(&audit_filter_mutex); mutex_unlock(&audit_cmd_mutex); |
74c3cbe33
|
824 825 826 827 828 |
} /* * Here comes the stuff asynchronous to auditctl operations */ |
74c3cbe33
|
829 830 831 |
static void evict_chunk(struct audit_chunk *chunk) { struct audit_tree *owner; |
916d75761
|
832 833 |
struct list_head *postponed = audit_killed_trees(); int need_prune = 0; |
74c3cbe33
|
834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 |
int n; if (chunk->dead) return; chunk->dead = 1; mutex_lock(&audit_filter_mutex); spin_lock(&hash_lock); while (!list_empty(&chunk->trees)) { owner = list_entry(chunk->trees.next, struct audit_tree, same_root); owner->goner = 1; owner->root = NULL; list_del_init(&owner->same_root); spin_unlock(&hash_lock); |
916d75761
|
849 850 851 852 853 854 855 |
if (!postponed) { kill_rules(owner); list_move(&owner->list, &prune_list); need_prune = 1; } else { list_move(&owner->list, postponed); } |
74c3cbe33
|
856 857 858 859 860 861 |
spin_lock(&hash_lock); } list_del_rcu(&chunk->hash); for (n = 0; n < chunk->count; n++) list_del_init(&chunk->owners[n].list); spin_unlock(&hash_lock); |
916d75761
|
862 863 |
if (need_prune) audit_schedule_prune(); |
74c3cbe33
|
864 865 |
mutex_unlock(&audit_filter_mutex); } |
3a9b16b40
|
866 |
static int audit_tree_handle_event(struct fsnotify_group *group, |
ce8f76fb7
|
867 868 |
struct fsnotify_mark *inode_mark, struct fsnotify_mark *vfsmonut_mark, |
3a9b16b40
|
869 |
struct fsnotify_event *event) |
74c3cbe33
|
870 |
{ |
28a3a7eb3
|
871 872 873 |
BUG(); return -EOPNOTSUPP; } |
74c3cbe33
|
874 |
|
e61ce8673
|
875 |
static void audit_tree_freeing_mark(struct fsnotify_mark *entry, struct fsnotify_group *group) |
28a3a7eb3
|
876 877 878 879 880 |
{ struct audit_chunk *chunk = container_of(entry, struct audit_chunk, mark); evict_chunk(chunk); fsnotify_put_mark(entry); |
74c3cbe33
|
881 |
} |
7b0a04fbf
|
882 |
static bool audit_tree_send_event(struct fsnotify_group *group, struct inode *inode, |
1968f5eed
|
883 |
struct fsnotify_mark *inode_mark, |
ce8f76fb7
|
884 |
struct fsnotify_mark *vfsmount_mark, |
3a9b16b40
|
885 |
__u32 mask, void *data, int data_type) |
74c3cbe33
|
886 |
{ |
2612abb51
|
887 |
return false; |
74c3cbe33
|
888 |
} |
28a3a7eb3
|
889 890 891 892 893 894 |
static const struct fsnotify_ops audit_tree_ops = { .handle_event = audit_tree_handle_event, .should_send_event = audit_tree_send_event, .free_group_priv = NULL, .free_event_priv = NULL, .freeing_mark = audit_tree_freeing_mark, |
74c3cbe33
|
895 896 897 898 899 |
}; static int __init audit_tree_init(void) { int i; |
0d2e2a1d0
|
900 |
audit_tree_group = fsnotify_alloc_group(&audit_tree_ops); |
28a3a7eb3
|
901 902 |
if (IS_ERR(audit_tree_group)) audit_panic("cannot initialize fsnotify group for rectree watches"); |
74c3cbe33
|
903 904 905 906 907 908 909 |
for (i = 0; i < HASH_SIZE; i++) INIT_LIST_HEAD(&chunk_hash_heads[i]); return 0; } __initcall(audit_tree_init); |