174c3cbe3SAl Viro #include "audit.h" 228a3a7ebSEric Paris #include <linux/fsnotify_backend.h> 374c3cbe3SAl Viro #include <linux/namei.h> 474c3cbe3SAl Viro #include <linux/mount.h> 5916d7576SAl Viro #include <linux/kthread.h> 65a0e3ad6STejun Heo #include <linux/slab.h> 774c3cbe3SAl Viro 874c3cbe3SAl Viro struct audit_tree; 974c3cbe3SAl Viro struct audit_chunk; 1074c3cbe3SAl Viro 1174c3cbe3SAl Viro struct audit_tree { 1274c3cbe3SAl Viro atomic_t count; 1374c3cbe3SAl Viro int goner; 1474c3cbe3SAl Viro struct audit_chunk *root; 1574c3cbe3SAl Viro struct list_head chunks; 1674c3cbe3SAl Viro struct list_head rules; 1774c3cbe3SAl Viro struct list_head list; 1874c3cbe3SAl Viro struct list_head same_root; 1974c3cbe3SAl Viro struct rcu_head head; 2074c3cbe3SAl Viro char pathname[]; 2174c3cbe3SAl Viro }; 2274c3cbe3SAl Viro 2374c3cbe3SAl Viro struct audit_chunk { 2474c3cbe3SAl Viro struct list_head hash; 25e61ce867SEric Paris struct fsnotify_mark mark; 2674c3cbe3SAl Viro struct list_head trees; /* with root here */ 2774c3cbe3SAl Viro int dead; 2874c3cbe3SAl Viro int count; 298f7b0ba1SAl Viro atomic_long_t refs; 3074c3cbe3SAl Viro struct rcu_head head; 3174c3cbe3SAl Viro struct node { 3274c3cbe3SAl Viro struct list_head list; 3374c3cbe3SAl Viro struct audit_tree *owner; 3474c3cbe3SAl Viro unsigned index; /* index; upper bit indicates 'will prune' */ 3574c3cbe3SAl Viro } owners[]; 3674c3cbe3SAl Viro }; 3774c3cbe3SAl Viro 3874c3cbe3SAl Viro static LIST_HEAD(tree_list); 3974c3cbe3SAl Viro static LIST_HEAD(prune_list); 4074c3cbe3SAl Viro 4174c3cbe3SAl Viro /* 4274c3cbe3SAl Viro * One struct chunk is attached to each inode of interest. 4374c3cbe3SAl Viro * We replace struct chunk on tagging/untagging. 4474c3cbe3SAl Viro * Rules have pointer to struct audit_tree. 4574c3cbe3SAl Viro * Rules have struct list_head rlist forming a list of rules over 4674c3cbe3SAl Viro * the same tree. 4774c3cbe3SAl Viro * References to struct chunk are collected at audit_inode{,_child}() 4874c3cbe3SAl Viro * time and used in AUDIT_TREE rule matching. 4974c3cbe3SAl Viro * These references are dropped at the same time we are calling 5074c3cbe3SAl Viro * audit_free_names(), etc. 5174c3cbe3SAl Viro * 5274c3cbe3SAl Viro * Cyclic lists galore: 5374c3cbe3SAl Viro * tree.chunks anchors chunk.owners[].list hash_lock 5474c3cbe3SAl Viro * tree.rules anchors rule.rlist audit_filter_mutex 5574c3cbe3SAl Viro * chunk.trees anchors tree.same_root hash_lock 5674c3cbe3SAl Viro * chunk.hash is a hash with middle bits of watch.inode as 5774c3cbe3SAl Viro * a hash function. RCU, hash_lock 5874c3cbe3SAl Viro * 5974c3cbe3SAl Viro * tree is refcounted; one reference for "some rules on rules_list refer to 6074c3cbe3SAl Viro * it", one for each chunk with pointer to it. 6174c3cbe3SAl Viro * 6228a3a7ebSEric Paris * chunk is refcounted by embedded fsnotify_mark + .refs (non-zero refcount 638f7b0ba1SAl Viro * of watch contributes 1 to .refs). 6474c3cbe3SAl Viro * 6574c3cbe3SAl Viro * node.index allows to get from node.list to containing chunk. 6674c3cbe3SAl Viro * MSB of that sucker is stolen to mark taggings that we might have to 6774c3cbe3SAl Viro * revert - several operations have very unpleasant cleanup logics and 6874c3cbe3SAl Viro * that makes a difference. Some. 6974c3cbe3SAl Viro */ 7074c3cbe3SAl Viro 7128a3a7ebSEric Paris static struct fsnotify_group *audit_tree_group; 7274c3cbe3SAl Viro 7374c3cbe3SAl Viro static struct audit_tree *alloc_tree(const char *s) 7474c3cbe3SAl Viro { 7574c3cbe3SAl Viro struct audit_tree *tree; 7674c3cbe3SAl Viro 7774c3cbe3SAl Viro tree = kmalloc(sizeof(struct audit_tree) + strlen(s) + 1, GFP_KERNEL); 7874c3cbe3SAl Viro if (tree) { 7974c3cbe3SAl Viro atomic_set(&tree->count, 1); 8074c3cbe3SAl Viro tree->goner = 0; 8174c3cbe3SAl Viro INIT_LIST_HEAD(&tree->chunks); 8274c3cbe3SAl Viro INIT_LIST_HEAD(&tree->rules); 8374c3cbe3SAl Viro INIT_LIST_HEAD(&tree->list); 8474c3cbe3SAl Viro INIT_LIST_HEAD(&tree->same_root); 8574c3cbe3SAl Viro tree->root = NULL; 8674c3cbe3SAl Viro strcpy(tree->pathname, s); 8774c3cbe3SAl Viro } 8874c3cbe3SAl Viro return tree; 8974c3cbe3SAl Viro } 9074c3cbe3SAl Viro 9174c3cbe3SAl Viro static inline void get_tree(struct audit_tree *tree) 9274c3cbe3SAl Viro { 9374c3cbe3SAl Viro atomic_inc(&tree->count); 9474c3cbe3SAl Viro } 9574c3cbe3SAl Viro 9674c3cbe3SAl Viro static inline void put_tree(struct audit_tree *tree) 9774c3cbe3SAl Viro { 9874c3cbe3SAl Viro if (atomic_dec_and_test(&tree->count)) 993b097c46SLai Jiangshan kfree_rcu(tree, head); 10074c3cbe3SAl Viro } 10174c3cbe3SAl Viro 10274c3cbe3SAl Viro /* to avoid bringing the entire thing in audit.h */ 10374c3cbe3SAl Viro const char *audit_tree_path(struct audit_tree *tree) 10474c3cbe3SAl Viro { 10574c3cbe3SAl Viro return tree->pathname; 10674c3cbe3SAl Viro } 10774c3cbe3SAl Viro 1088f7b0ba1SAl Viro static void free_chunk(struct audit_chunk *chunk) 10974c3cbe3SAl Viro { 11074c3cbe3SAl Viro int i; 11174c3cbe3SAl Viro 11274c3cbe3SAl Viro for (i = 0; i < chunk->count; i++) { 11374c3cbe3SAl Viro if (chunk->owners[i].owner) 11474c3cbe3SAl Viro put_tree(chunk->owners[i].owner); 11574c3cbe3SAl Viro } 11674c3cbe3SAl Viro kfree(chunk); 11774c3cbe3SAl Viro } 11874c3cbe3SAl Viro 11974c3cbe3SAl Viro void audit_put_chunk(struct audit_chunk *chunk) 12074c3cbe3SAl Viro { 1218f7b0ba1SAl Viro if (atomic_long_dec_and_test(&chunk->refs)) 1228f7b0ba1SAl Viro free_chunk(chunk); 1238f7b0ba1SAl Viro } 1248f7b0ba1SAl Viro 1258f7b0ba1SAl Viro static void __put_chunk(struct rcu_head *rcu) 1268f7b0ba1SAl Viro { 1278f7b0ba1SAl Viro struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head); 1288f7b0ba1SAl Viro audit_put_chunk(chunk); 12974c3cbe3SAl Viro } 13074c3cbe3SAl Viro 131e61ce867SEric Paris static void audit_tree_destroy_watch(struct fsnotify_mark *entry) 13228a3a7ebSEric Paris { 13328a3a7ebSEric Paris struct audit_chunk *chunk = container_of(entry, struct audit_chunk, mark); 13428a3a7ebSEric Paris call_rcu(&chunk->head, __put_chunk); 13528a3a7ebSEric Paris } 13628a3a7ebSEric Paris 13728a3a7ebSEric Paris static struct audit_chunk *alloc_chunk(int count) 13828a3a7ebSEric Paris { 13928a3a7ebSEric Paris struct audit_chunk *chunk; 14028a3a7ebSEric Paris size_t size; 14128a3a7ebSEric Paris int i; 14228a3a7ebSEric Paris 14328a3a7ebSEric Paris size = offsetof(struct audit_chunk, owners) + count * sizeof(struct node); 14428a3a7ebSEric Paris chunk = kzalloc(size, GFP_KERNEL); 14528a3a7ebSEric Paris if (!chunk) 14628a3a7ebSEric Paris return NULL; 14728a3a7ebSEric Paris 14828a3a7ebSEric Paris INIT_LIST_HEAD(&chunk->hash); 14928a3a7ebSEric Paris INIT_LIST_HEAD(&chunk->trees); 15028a3a7ebSEric Paris chunk->count = count; 15128a3a7ebSEric Paris atomic_long_set(&chunk->refs, 1); 15228a3a7ebSEric Paris for (i = 0; i < count; i++) { 15328a3a7ebSEric Paris INIT_LIST_HEAD(&chunk->owners[i].list); 15428a3a7ebSEric Paris chunk->owners[i].index = i; 15528a3a7ebSEric Paris } 15628a3a7ebSEric Paris fsnotify_init_mark(&chunk->mark, audit_tree_destroy_watch); 15728a3a7ebSEric Paris return chunk; 15828a3a7ebSEric Paris } 15928a3a7ebSEric Paris 16074c3cbe3SAl Viro enum {HASH_SIZE = 128}; 16174c3cbe3SAl Viro static struct list_head chunk_hash_heads[HASH_SIZE]; 16274c3cbe3SAl Viro static __cacheline_aligned_in_smp DEFINE_SPINLOCK(hash_lock); 16374c3cbe3SAl Viro 16474c3cbe3SAl Viro static inline struct list_head *chunk_hash(const struct inode *inode) 16574c3cbe3SAl Viro { 16674c3cbe3SAl Viro unsigned long n = (unsigned long)inode / L1_CACHE_BYTES; 16774c3cbe3SAl Viro return chunk_hash_heads + n % HASH_SIZE; 16874c3cbe3SAl Viro } 16974c3cbe3SAl Viro 17028a3a7ebSEric Paris /* hash_lock & entry->lock is held by caller */ 17174c3cbe3SAl Viro static void insert_hash(struct audit_chunk *chunk) 17274c3cbe3SAl Viro { 173e61ce867SEric Paris struct fsnotify_mark *entry = &chunk->mark; 17428a3a7ebSEric Paris struct list_head *list; 17528a3a7ebSEric Paris 1762823e04dSEric Paris if (!entry->i.inode) 17728a3a7ebSEric Paris return; 1782823e04dSEric Paris list = chunk_hash(entry->i.inode); 17974c3cbe3SAl Viro list_add_rcu(&chunk->hash, list); 18074c3cbe3SAl Viro } 18174c3cbe3SAl Viro 18274c3cbe3SAl Viro /* called under rcu_read_lock */ 18374c3cbe3SAl Viro struct audit_chunk *audit_tree_lookup(const struct inode *inode) 18474c3cbe3SAl Viro { 18574c3cbe3SAl Viro struct list_head *list = chunk_hash(inode); 1866793a051SPaul E. McKenney struct audit_chunk *p; 18774c3cbe3SAl Viro 1886793a051SPaul E. McKenney list_for_each_entry_rcu(p, list, hash) { 18928a3a7ebSEric Paris /* mark.inode may have gone NULL, but who cares? */ 1902823e04dSEric Paris if (p->mark.i.inode == inode) { 1918f7b0ba1SAl Viro atomic_long_inc(&p->refs); 19274c3cbe3SAl Viro return p; 19374c3cbe3SAl Viro } 19474c3cbe3SAl Viro } 19574c3cbe3SAl Viro return NULL; 19674c3cbe3SAl Viro } 19774c3cbe3SAl Viro 19874c3cbe3SAl Viro int audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree) 19974c3cbe3SAl Viro { 20074c3cbe3SAl Viro int n; 20174c3cbe3SAl Viro for (n = 0; n < chunk->count; n++) 20274c3cbe3SAl Viro if (chunk->owners[n].owner == tree) 20374c3cbe3SAl Viro return 1; 20474c3cbe3SAl Viro return 0; 20574c3cbe3SAl Viro } 20674c3cbe3SAl Viro 20774c3cbe3SAl Viro /* tagging and untagging inodes with trees */ 20874c3cbe3SAl Viro 2098f7b0ba1SAl Viro static struct audit_chunk *find_chunk(struct node *p) 21074c3cbe3SAl Viro { 2118f7b0ba1SAl Viro int index = p->index & ~(1U<<31); 2128f7b0ba1SAl Viro p -= index; 2138f7b0ba1SAl Viro return container_of(p, struct audit_chunk, owners[0]); 2148f7b0ba1SAl Viro } 2158f7b0ba1SAl Viro 2168f7b0ba1SAl Viro static void untag_chunk(struct node *p) 2178f7b0ba1SAl Viro { 2188f7b0ba1SAl Viro struct audit_chunk *chunk = find_chunk(p); 219e61ce867SEric Paris struct fsnotify_mark *entry = &chunk->mark; 220f7a998a9SAl Viro struct audit_chunk *new = NULL; 22174c3cbe3SAl Viro struct audit_tree *owner; 22274c3cbe3SAl Viro int size = chunk->count - 1; 22374c3cbe3SAl Viro int i, j; 22474c3cbe3SAl Viro 22528a3a7ebSEric Paris fsnotify_get_mark(entry); 2268f7b0ba1SAl Viro 2278f7b0ba1SAl Viro spin_unlock(&hash_lock); 2288f7b0ba1SAl Viro 229f7a998a9SAl Viro if (size) 230f7a998a9SAl Viro new = alloc_chunk(size); 231f7a998a9SAl Viro 23228a3a7ebSEric Paris spin_lock(&entry->lock); 2332823e04dSEric Paris if (chunk->dead || !entry->i.inode) { 23428a3a7ebSEric Paris spin_unlock(&entry->lock); 235f7a998a9SAl Viro if (new) 236f7a998a9SAl Viro free_chunk(new); 2378f7b0ba1SAl Viro goto out; 23874c3cbe3SAl Viro } 23974c3cbe3SAl Viro 24074c3cbe3SAl Viro owner = p->owner; 24174c3cbe3SAl Viro 24274c3cbe3SAl Viro if (!size) { 24374c3cbe3SAl Viro chunk->dead = 1; 24474c3cbe3SAl Viro spin_lock(&hash_lock); 24574c3cbe3SAl Viro list_del_init(&chunk->trees); 24674c3cbe3SAl Viro if (owner->root == chunk) 24774c3cbe3SAl Viro owner->root = NULL; 24874c3cbe3SAl Viro list_del_init(&p->list); 24974c3cbe3SAl Viro list_del_rcu(&chunk->hash); 25074c3cbe3SAl Viro spin_unlock(&hash_lock); 25128a3a7ebSEric Paris spin_unlock(&entry->lock); 252e2a29943SLino Sanfilippo fsnotify_destroy_mark(entry, audit_tree_group); 2538f7b0ba1SAl Viro goto out; 25474c3cbe3SAl Viro } 25574c3cbe3SAl Viro 25674c3cbe3SAl Viro if (!new) 25774c3cbe3SAl Viro goto Fallback; 258f7a998a9SAl Viro 25928a3a7ebSEric Paris fsnotify_duplicate_mark(&new->mark, entry); 2605444e298SEric Paris if (fsnotify_add_mark(&new->mark, new->mark.group, new->mark.i.inode, NULL, 1)) { 2610fe33aaeSMiklos Szeredi fsnotify_put_mark(&new->mark); 26274c3cbe3SAl Viro goto Fallback; 26374c3cbe3SAl Viro } 26474c3cbe3SAl Viro 26574c3cbe3SAl Viro chunk->dead = 1; 26674c3cbe3SAl Viro spin_lock(&hash_lock); 26774c3cbe3SAl Viro list_replace_init(&chunk->trees, &new->trees); 26874c3cbe3SAl Viro if (owner->root == chunk) { 26974c3cbe3SAl Viro list_del_init(&owner->same_root); 27074c3cbe3SAl Viro owner->root = NULL; 27174c3cbe3SAl Viro } 27274c3cbe3SAl Viro 2736f5d5114SAl Viro for (i = j = 0; j <= size; i++, j++) { 27474c3cbe3SAl Viro struct audit_tree *s; 27574c3cbe3SAl Viro if (&chunk->owners[j] == p) { 27674c3cbe3SAl Viro list_del_init(&p->list); 27774c3cbe3SAl Viro i--; 27874c3cbe3SAl Viro continue; 27974c3cbe3SAl Viro } 28074c3cbe3SAl Viro s = chunk->owners[j].owner; 28174c3cbe3SAl Viro new->owners[i].owner = s; 28274c3cbe3SAl Viro new->owners[i].index = chunk->owners[j].index - j + i; 28374c3cbe3SAl Viro if (!s) /* result of earlier fallback */ 28474c3cbe3SAl Viro continue; 28574c3cbe3SAl Viro get_tree(s); 2866f5d5114SAl Viro list_replace_init(&chunk->owners[j].list, &new->owners[i].list); 28774c3cbe3SAl Viro } 28874c3cbe3SAl Viro 28974c3cbe3SAl Viro list_replace_rcu(&chunk->hash, &new->hash); 29074c3cbe3SAl Viro list_for_each_entry(owner, &new->trees, same_root) 29174c3cbe3SAl Viro owner->root = new; 29274c3cbe3SAl Viro spin_unlock(&hash_lock); 29328a3a7ebSEric Paris spin_unlock(&entry->lock); 294e2a29943SLino Sanfilippo fsnotify_destroy_mark(entry, audit_tree_group); 295b3e8692bSMiklos Szeredi fsnotify_put_mark(&new->mark); /* drop initial reference */ 2968f7b0ba1SAl Viro goto out; 29774c3cbe3SAl Viro 29874c3cbe3SAl Viro Fallback: 29974c3cbe3SAl Viro // do the best we can 30074c3cbe3SAl Viro spin_lock(&hash_lock); 30174c3cbe3SAl Viro if (owner->root == chunk) { 30274c3cbe3SAl Viro list_del_init(&owner->same_root); 30374c3cbe3SAl Viro owner->root = NULL; 30474c3cbe3SAl Viro } 30574c3cbe3SAl Viro list_del_init(&p->list); 30674c3cbe3SAl Viro p->owner = NULL; 30774c3cbe3SAl Viro put_tree(owner); 30874c3cbe3SAl Viro spin_unlock(&hash_lock); 30928a3a7ebSEric Paris spin_unlock(&entry->lock); 3108f7b0ba1SAl Viro out: 31128a3a7ebSEric Paris fsnotify_put_mark(entry); 3128f7b0ba1SAl Viro spin_lock(&hash_lock); 31374c3cbe3SAl Viro } 31474c3cbe3SAl Viro 31574c3cbe3SAl Viro static int create_chunk(struct inode *inode, struct audit_tree *tree) 31674c3cbe3SAl Viro { 317e61ce867SEric Paris struct fsnotify_mark *entry; 31874c3cbe3SAl Viro struct audit_chunk *chunk = alloc_chunk(1); 31974c3cbe3SAl Viro if (!chunk) 32074c3cbe3SAl Viro return -ENOMEM; 32174c3cbe3SAl Viro 32228a3a7ebSEric Paris entry = &chunk->mark; 3235444e298SEric Paris if (fsnotify_add_mark(entry, audit_tree_group, inode, NULL, 0)) { 3240fe33aaeSMiklos Szeredi fsnotify_put_mark(entry); 32574c3cbe3SAl Viro return -ENOSPC; 32674c3cbe3SAl Viro } 32774c3cbe3SAl Viro 32828a3a7ebSEric Paris spin_lock(&entry->lock); 32974c3cbe3SAl Viro spin_lock(&hash_lock); 33074c3cbe3SAl Viro if (tree->goner) { 33174c3cbe3SAl Viro spin_unlock(&hash_lock); 33274c3cbe3SAl Viro chunk->dead = 1; 33328a3a7ebSEric Paris spin_unlock(&entry->lock); 334e2a29943SLino Sanfilippo fsnotify_destroy_mark(entry, audit_tree_group); 33528a3a7ebSEric Paris fsnotify_put_mark(entry); 33674c3cbe3SAl Viro return 0; 33774c3cbe3SAl Viro } 33874c3cbe3SAl Viro chunk->owners[0].index = (1U << 31); 33974c3cbe3SAl Viro chunk->owners[0].owner = tree; 34074c3cbe3SAl Viro get_tree(tree); 34174c3cbe3SAl Viro list_add(&chunk->owners[0].list, &tree->chunks); 34274c3cbe3SAl Viro if (!tree->root) { 34374c3cbe3SAl Viro tree->root = chunk; 34474c3cbe3SAl Viro list_add(&tree->same_root, &chunk->trees); 34574c3cbe3SAl Viro } 34674c3cbe3SAl Viro insert_hash(chunk); 34774c3cbe3SAl Viro spin_unlock(&hash_lock); 34828a3a7ebSEric Paris spin_unlock(&entry->lock); 349b3e8692bSMiklos Szeredi fsnotify_put_mark(entry); /* drop initial reference */ 35074c3cbe3SAl Viro return 0; 35174c3cbe3SAl Viro } 35274c3cbe3SAl Viro 35374c3cbe3SAl Viro /* the first tagged inode becomes root of tree */ 35474c3cbe3SAl Viro static int tag_chunk(struct inode *inode, struct audit_tree *tree) 35574c3cbe3SAl Viro { 356e61ce867SEric Paris struct fsnotify_mark *old_entry, *chunk_entry; 35774c3cbe3SAl Viro struct audit_tree *owner; 35874c3cbe3SAl Viro struct audit_chunk *chunk, *old; 35974c3cbe3SAl Viro struct node *p; 36074c3cbe3SAl Viro int n; 36174c3cbe3SAl Viro 3625444e298SEric Paris old_entry = fsnotify_find_inode_mark(audit_tree_group, inode); 36328a3a7ebSEric Paris if (!old_entry) 36474c3cbe3SAl Viro return create_chunk(inode, tree); 36574c3cbe3SAl Viro 36628a3a7ebSEric Paris old = container_of(old_entry, struct audit_chunk, mark); 36774c3cbe3SAl Viro 36874c3cbe3SAl Viro /* are we already there? */ 36974c3cbe3SAl Viro spin_lock(&hash_lock); 37074c3cbe3SAl Viro for (n = 0; n < old->count; n++) { 37174c3cbe3SAl Viro if (old->owners[n].owner == tree) { 37274c3cbe3SAl Viro spin_unlock(&hash_lock); 37328a3a7ebSEric Paris fsnotify_put_mark(old_entry); 37474c3cbe3SAl Viro return 0; 37574c3cbe3SAl Viro } 37674c3cbe3SAl Viro } 37774c3cbe3SAl Viro spin_unlock(&hash_lock); 37874c3cbe3SAl Viro 37974c3cbe3SAl Viro chunk = alloc_chunk(old->count + 1); 380b4c30aadSAl Viro if (!chunk) { 38128a3a7ebSEric Paris fsnotify_put_mark(old_entry); 38274c3cbe3SAl Viro return -ENOMEM; 383b4c30aadSAl Viro } 38474c3cbe3SAl Viro 38528a3a7ebSEric Paris chunk_entry = &chunk->mark; 38628a3a7ebSEric Paris 38728a3a7ebSEric Paris spin_lock(&old_entry->lock); 3882823e04dSEric Paris if (!old_entry->i.inode) { 38928a3a7ebSEric Paris /* old_entry is being shot, lets just lie */ 39028a3a7ebSEric Paris spin_unlock(&old_entry->lock); 39128a3a7ebSEric Paris fsnotify_put_mark(old_entry); 39274c3cbe3SAl Viro free_chunk(chunk); 39328a3a7ebSEric Paris return -ENOENT; 39428a3a7ebSEric Paris } 39528a3a7ebSEric Paris 39628a3a7ebSEric Paris fsnotify_duplicate_mark(chunk_entry, old_entry); 3975444e298SEric Paris if (fsnotify_add_mark(chunk_entry, chunk_entry->group, chunk_entry->i.inode, NULL, 1)) { 39828a3a7ebSEric Paris spin_unlock(&old_entry->lock); 3990fe33aaeSMiklos Szeredi fsnotify_put_mark(chunk_entry); 40028a3a7ebSEric Paris fsnotify_put_mark(old_entry); 40174c3cbe3SAl Viro return -ENOSPC; 40274c3cbe3SAl Viro } 40328a3a7ebSEric Paris 40428a3a7ebSEric Paris /* even though we hold old_entry->lock, this is safe since chunk_entry->lock could NEVER have been grabbed before */ 40528a3a7ebSEric Paris spin_lock(&chunk_entry->lock); 40674c3cbe3SAl Viro spin_lock(&hash_lock); 40728a3a7ebSEric Paris 40828a3a7ebSEric Paris /* we now hold old_entry->lock, chunk_entry->lock, and hash_lock */ 40974c3cbe3SAl Viro if (tree->goner) { 41074c3cbe3SAl Viro spin_unlock(&hash_lock); 41174c3cbe3SAl Viro chunk->dead = 1; 41228a3a7ebSEric Paris spin_unlock(&chunk_entry->lock); 41328a3a7ebSEric Paris spin_unlock(&old_entry->lock); 41428a3a7ebSEric Paris 415e2a29943SLino Sanfilippo fsnotify_destroy_mark(chunk_entry, audit_tree_group); 41628a3a7ebSEric Paris 41728a3a7ebSEric Paris fsnotify_put_mark(chunk_entry); 41828a3a7ebSEric Paris fsnotify_put_mark(old_entry); 41974c3cbe3SAl Viro return 0; 42074c3cbe3SAl Viro } 42174c3cbe3SAl Viro list_replace_init(&old->trees, &chunk->trees); 42274c3cbe3SAl Viro for (n = 0, p = chunk->owners; n < old->count; n++, p++) { 42374c3cbe3SAl Viro struct audit_tree *s = old->owners[n].owner; 42474c3cbe3SAl Viro p->owner = s; 42574c3cbe3SAl Viro p->index = old->owners[n].index; 42674c3cbe3SAl Viro if (!s) /* result of fallback in untag */ 42774c3cbe3SAl Viro continue; 42874c3cbe3SAl Viro get_tree(s); 42974c3cbe3SAl Viro list_replace_init(&old->owners[n].list, &p->list); 43074c3cbe3SAl Viro } 43174c3cbe3SAl Viro p->index = (chunk->count - 1) | (1U<<31); 43274c3cbe3SAl Viro p->owner = tree; 43374c3cbe3SAl Viro get_tree(tree); 43474c3cbe3SAl Viro list_add(&p->list, &tree->chunks); 43574c3cbe3SAl Viro list_replace_rcu(&old->hash, &chunk->hash); 43674c3cbe3SAl Viro list_for_each_entry(owner, &chunk->trees, same_root) 43774c3cbe3SAl Viro owner->root = chunk; 43874c3cbe3SAl Viro old->dead = 1; 43974c3cbe3SAl Viro if (!tree->root) { 44074c3cbe3SAl Viro tree->root = chunk; 44174c3cbe3SAl Viro list_add(&tree->same_root, &chunk->trees); 44274c3cbe3SAl Viro } 44374c3cbe3SAl Viro spin_unlock(&hash_lock); 44428a3a7ebSEric Paris spin_unlock(&chunk_entry->lock); 44528a3a7ebSEric Paris spin_unlock(&old_entry->lock); 446e2a29943SLino Sanfilippo fsnotify_destroy_mark(old_entry, audit_tree_group); 447b3e8692bSMiklos Szeredi fsnotify_put_mark(chunk_entry); /* drop initial reference */ 44828a3a7ebSEric Paris fsnotify_put_mark(old_entry); /* pair to fsnotify_find mark_entry */ 44974c3cbe3SAl Viro return 0; 45074c3cbe3SAl Viro } 45174c3cbe3SAl Viro 4520644ec0cSKees Cook static void audit_log_remove_rule(struct audit_krule *rule) 45374c3cbe3SAl Viro { 45474c3cbe3SAl Viro struct audit_buffer *ab; 45574c3cbe3SAl Viro 45674c3cbe3SAl Viro ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); 4570644ec0cSKees Cook if (unlikely(!ab)) 4580644ec0cSKees Cook return; 4599d960985SEric Paris audit_log_format(ab, "op="); 460e7df61f4SBurn Alting audit_log_string(ab, "remove_rule"); 4619d960985SEric Paris audit_log_format(ab, " dir="); 46274c3cbe3SAl Viro audit_log_untrustedstring(ab, rule->tree->pathname); 4639d960985SEric Paris audit_log_key(ab, rule->filterkey); 46474c3cbe3SAl Viro audit_log_format(ab, " list=%d res=1", rule->listnr); 46574c3cbe3SAl Viro audit_log_end(ab); 4660644ec0cSKees Cook } 4670644ec0cSKees Cook 4680644ec0cSKees Cook static void kill_rules(struct audit_tree *tree) 4690644ec0cSKees Cook { 4700644ec0cSKees Cook struct audit_krule *rule, *next; 4710644ec0cSKees Cook struct audit_entry *entry; 4720644ec0cSKees Cook 4730644ec0cSKees Cook list_for_each_entry_safe(rule, next, &tree->rules, rlist) { 4740644ec0cSKees Cook entry = container_of(rule, struct audit_entry, rule); 4750644ec0cSKees Cook 4760644ec0cSKees Cook list_del_init(&rule->rlist); 4770644ec0cSKees Cook if (rule->tree) { 4780644ec0cSKees Cook /* not a half-baked one */ 4790644ec0cSKees Cook audit_log_remove_rule(rule); 48074c3cbe3SAl Viro rule->tree = NULL; 48174c3cbe3SAl Viro list_del_rcu(&entry->list); 482e45aa212SAl Viro list_del(&entry->rule.list); 48374c3cbe3SAl Viro call_rcu(&entry->rcu, audit_free_rule_rcu); 48474c3cbe3SAl Viro } 48574c3cbe3SAl Viro } 48674c3cbe3SAl Viro } 48774c3cbe3SAl Viro 48874c3cbe3SAl Viro /* 48974c3cbe3SAl Viro * finish killing struct audit_tree 49074c3cbe3SAl Viro */ 49174c3cbe3SAl Viro static void prune_one(struct audit_tree *victim) 49274c3cbe3SAl Viro { 49374c3cbe3SAl Viro spin_lock(&hash_lock); 49474c3cbe3SAl Viro while (!list_empty(&victim->chunks)) { 49574c3cbe3SAl Viro struct node *p; 49674c3cbe3SAl Viro 49774c3cbe3SAl Viro p = list_entry(victim->chunks.next, struct node, list); 49874c3cbe3SAl Viro 4998f7b0ba1SAl Viro untag_chunk(p); 50074c3cbe3SAl Viro } 50174c3cbe3SAl Viro spin_unlock(&hash_lock); 50274c3cbe3SAl Viro put_tree(victim); 50374c3cbe3SAl Viro } 50474c3cbe3SAl Viro 50574c3cbe3SAl Viro /* trim the uncommitted chunks from tree */ 50674c3cbe3SAl Viro 50774c3cbe3SAl Viro static void trim_marked(struct audit_tree *tree) 50874c3cbe3SAl Viro { 50974c3cbe3SAl Viro struct list_head *p, *q; 51074c3cbe3SAl Viro spin_lock(&hash_lock); 51174c3cbe3SAl Viro if (tree->goner) { 51274c3cbe3SAl Viro spin_unlock(&hash_lock); 51374c3cbe3SAl Viro return; 51474c3cbe3SAl Viro } 51574c3cbe3SAl Viro /* reorder */ 51674c3cbe3SAl Viro for (p = tree->chunks.next; p != &tree->chunks; p = q) { 51774c3cbe3SAl Viro struct node *node = list_entry(p, struct node, list); 51874c3cbe3SAl Viro q = p->next; 51974c3cbe3SAl Viro if (node->index & (1U<<31)) { 52074c3cbe3SAl Viro list_del_init(p); 52174c3cbe3SAl Viro list_add(p, &tree->chunks); 52274c3cbe3SAl Viro } 52374c3cbe3SAl Viro } 52474c3cbe3SAl Viro 52574c3cbe3SAl Viro while (!list_empty(&tree->chunks)) { 52674c3cbe3SAl Viro struct node *node; 52774c3cbe3SAl Viro 52874c3cbe3SAl Viro node = list_entry(tree->chunks.next, struct node, list); 52974c3cbe3SAl Viro 53074c3cbe3SAl Viro /* have we run out of marked? */ 53174c3cbe3SAl Viro if (!(node->index & (1U<<31))) 53274c3cbe3SAl Viro break; 53374c3cbe3SAl Viro 5348f7b0ba1SAl Viro untag_chunk(node); 53574c3cbe3SAl Viro } 53674c3cbe3SAl Viro if (!tree->root && !tree->goner) { 53774c3cbe3SAl Viro tree->goner = 1; 53874c3cbe3SAl Viro spin_unlock(&hash_lock); 53974c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 54074c3cbe3SAl Viro kill_rules(tree); 54174c3cbe3SAl Viro list_del_init(&tree->list); 54274c3cbe3SAl Viro mutex_unlock(&audit_filter_mutex); 54374c3cbe3SAl Viro prune_one(tree); 54474c3cbe3SAl Viro } else { 54574c3cbe3SAl Viro spin_unlock(&hash_lock); 54674c3cbe3SAl Viro } 54774c3cbe3SAl Viro } 54874c3cbe3SAl Viro 549916d7576SAl Viro static void audit_schedule_prune(void); 550916d7576SAl Viro 55174c3cbe3SAl Viro /* called with audit_filter_mutex */ 55274c3cbe3SAl Viro int audit_remove_tree_rule(struct audit_krule *rule) 55374c3cbe3SAl Viro { 55474c3cbe3SAl Viro struct audit_tree *tree; 55574c3cbe3SAl Viro tree = rule->tree; 55674c3cbe3SAl Viro if (tree) { 55774c3cbe3SAl Viro spin_lock(&hash_lock); 55874c3cbe3SAl Viro list_del_init(&rule->rlist); 55974c3cbe3SAl Viro if (list_empty(&tree->rules) && !tree->goner) { 56074c3cbe3SAl Viro tree->root = NULL; 56174c3cbe3SAl Viro list_del_init(&tree->same_root); 56274c3cbe3SAl Viro tree->goner = 1; 56374c3cbe3SAl Viro list_move(&tree->list, &prune_list); 56474c3cbe3SAl Viro rule->tree = NULL; 56574c3cbe3SAl Viro spin_unlock(&hash_lock); 56674c3cbe3SAl Viro audit_schedule_prune(); 56774c3cbe3SAl Viro return 1; 56874c3cbe3SAl Viro } 56974c3cbe3SAl Viro rule->tree = NULL; 57074c3cbe3SAl Viro spin_unlock(&hash_lock); 57174c3cbe3SAl Viro return 1; 57274c3cbe3SAl Viro } 57374c3cbe3SAl Viro return 0; 57474c3cbe3SAl Viro } 57574c3cbe3SAl Viro 5761f707137SAl Viro static int compare_root(struct vfsmount *mnt, void *arg) 5771f707137SAl Viro { 5781f707137SAl Viro return mnt->mnt_root->d_inode == arg; 5791f707137SAl Viro } 5801f707137SAl Viro 58174c3cbe3SAl Viro void audit_trim_trees(void) 58274c3cbe3SAl Viro { 58374c3cbe3SAl Viro struct list_head cursor; 58474c3cbe3SAl Viro 58574c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 58674c3cbe3SAl Viro list_add(&cursor, &tree_list); 58774c3cbe3SAl Viro while (cursor.next != &tree_list) { 58874c3cbe3SAl Viro struct audit_tree *tree; 58998bc993fSAl Viro struct path path; 59074c3cbe3SAl Viro struct vfsmount *root_mnt; 59174c3cbe3SAl Viro struct node *node; 59274c3cbe3SAl Viro int err; 59374c3cbe3SAl Viro 59474c3cbe3SAl Viro tree = container_of(cursor.next, struct audit_tree, list); 59574c3cbe3SAl Viro get_tree(tree); 59674c3cbe3SAl Viro list_del(&cursor); 59774c3cbe3SAl Viro list_add(&cursor, &tree->list); 59874c3cbe3SAl Viro mutex_unlock(&audit_filter_mutex); 59974c3cbe3SAl Viro 60098bc993fSAl Viro err = kern_path(tree->pathname, 0, &path); 60174c3cbe3SAl Viro if (err) 60274c3cbe3SAl Viro goto skip_it; 60374c3cbe3SAl Viro 604589ff870SAl Viro root_mnt = collect_mounts(&path); 60598bc993fSAl Viro path_put(&path); 606be34d1a3SDavid Howells if (IS_ERR(root_mnt)) 60774c3cbe3SAl Viro goto skip_it; 60874c3cbe3SAl Viro 60974c3cbe3SAl Viro spin_lock(&hash_lock); 61074c3cbe3SAl Viro list_for_each_entry(node, &tree->chunks, list) { 61128a3a7ebSEric Paris struct audit_chunk *chunk = find_chunk(node); 61225985edcSLucas De Marchi /* this could be NULL if the watch is dying else where... */ 6132823e04dSEric Paris struct inode *inode = chunk->mark.i.inode; 61474c3cbe3SAl Viro node->index |= 1U<<31; 6151f707137SAl Viro if (iterate_mounts(compare_root, inode, root_mnt)) 61674c3cbe3SAl Viro node->index &= ~(1U<<31); 61774c3cbe3SAl Viro } 61874c3cbe3SAl Viro spin_unlock(&hash_lock); 61974c3cbe3SAl Viro trim_marked(tree); 62074c3cbe3SAl Viro drop_collected_mounts(root_mnt); 62174c3cbe3SAl Viro skip_it: 62212b2f117SChen Gang put_tree(tree); 62374c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 62474c3cbe3SAl Viro } 62574c3cbe3SAl Viro list_del(&cursor); 62674c3cbe3SAl Viro mutex_unlock(&audit_filter_mutex); 62774c3cbe3SAl Viro } 62874c3cbe3SAl Viro 62974c3cbe3SAl Viro int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op) 63074c3cbe3SAl Viro { 63174c3cbe3SAl Viro 63274c3cbe3SAl Viro if (pathname[0] != '/' || 63374c3cbe3SAl Viro rule->listnr != AUDIT_FILTER_EXIT || 6345af75d8dSAl Viro op != Audit_equal || 63574c3cbe3SAl Viro rule->inode_f || rule->watch || rule->tree) 63674c3cbe3SAl Viro return -EINVAL; 63774c3cbe3SAl Viro rule->tree = alloc_tree(pathname); 63874c3cbe3SAl Viro if (!rule->tree) 63974c3cbe3SAl Viro return -ENOMEM; 64074c3cbe3SAl Viro return 0; 64174c3cbe3SAl Viro } 64274c3cbe3SAl Viro 64374c3cbe3SAl Viro void audit_put_tree(struct audit_tree *tree) 64474c3cbe3SAl Viro { 64574c3cbe3SAl Viro put_tree(tree); 64674c3cbe3SAl Viro } 64774c3cbe3SAl Viro 6481f707137SAl Viro static int tag_mount(struct vfsmount *mnt, void *arg) 6491f707137SAl Viro { 6501f707137SAl Viro return tag_chunk(mnt->mnt_root->d_inode, arg); 6511f707137SAl Viro } 6521f707137SAl Viro 65374c3cbe3SAl Viro /* called with audit_filter_mutex */ 65474c3cbe3SAl Viro int audit_add_tree_rule(struct audit_krule *rule) 65574c3cbe3SAl Viro { 65674c3cbe3SAl Viro struct audit_tree *seed = rule->tree, *tree; 65798bc993fSAl Viro struct path path; 6581f707137SAl Viro struct vfsmount *mnt; 65974c3cbe3SAl Viro int err; 66074c3cbe3SAl Viro 661736f3203SChen Gang rule->tree = NULL; 66274c3cbe3SAl Viro list_for_each_entry(tree, &tree_list, list) { 66374c3cbe3SAl Viro if (!strcmp(seed->pathname, tree->pathname)) { 66474c3cbe3SAl Viro put_tree(seed); 66574c3cbe3SAl Viro rule->tree = tree; 66674c3cbe3SAl Viro list_add(&rule->rlist, &tree->rules); 66774c3cbe3SAl Viro return 0; 66874c3cbe3SAl Viro } 66974c3cbe3SAl Viro } 67074c3cbe3SAl Viro tree = seed; 67174c3cbe3SAl Viro list_add(&tree->list, &tree_list); 67274c3cbe3SAl Viro list_add(&rule->rlist, &tree->rules); 67374c3cbe3SAl Viro /* do not set rule->tree yet */ 67474c3cbe3SAl Viro mutex_unlock(&audit_filter_mutex); 67574c3cbe3SAl Viro 67698bc993fSAl Viro err = kern_path(tree->pathname, 0, &path); 67774c3cbe3SAl Viro if (err) 67874c3cbe3SAl Viro goto Err; 679589ff870SAl Viro mnt = collect_mounts(&path); 68098bc993fSAl Viro path_put(&path); 681be34d1a3SDavid Howells if (IS_ERR(mnt)) { 682be34d1a3SDavid Howells err = PTR_ERR(mnt); 68374c3cbe3SAl Viro goto Err; 68474c3cbe3SAl Viro } 68574c3cbe3SAl Viro 68674c3cbe3SAl Viro get_tree(tree); 6871f707137SAl Viro err = iterate_mounts(tag_mount, tree, mnt); 68874c3cbe3SAl Viro drop_collected_mounts(mnt); 68974c3cbe3SAl Viro 69074c3cbe3SAl Viro if (!err) { 69174c3cbe3SAl Viro struct node *node; 69274c3cbe3SAl Viro spin_lock(&hash_lock); 69374c3cbe3SAl Viro list_for_each_entry(node, &tree->chunks, list) 69474c3cbe3SAl Viro node->index &= ~(1U<<31); 69574c3cbe3SAl Viro spin_unlock(&hash_lock); 69674c3cbe3SAl Viro } else { 69774c3cbe3SAl Viro trim_marked(tree); 69874c3cbe3SAl Viro goto Err; 69974c3cbe3SAl Viro } 70074c3cbe3SAl Viro 70174c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 70274c3cbe3SAl Viro if (list_empty(&rule->rlist)) { 70374c3cbe3SAl Viro put_tree(tree); 70474c3cbe3SAl Viro return -ENOENT; 70574c3cbe3SAl Viro } 70674c3cbe3SAl Viro rule->tree = tree; 70774c3cbe3SAl Viro put_tree(tree); 70874c3cbe3SAl Viro 70974c3cbe3SAl Viro return 0; 71074c3cbe3SAl Viro Err: 71174c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 71274c3cbe3SAl Viro list_del_init(&tree->list); 71374c3cbe3SAl Viro list_del_init(&tree->rules); 71474c3cbe3SAl Viro put_tree(tree); 71574c3cbe3SAl Viro return err; 71674c3cbe3SAl Viro } 71774c3cbe3SAl Viro 71874c3cbe3SAl Viro int audit_tag_tree(char *old, char *new) 71974c3cbe3SAl Viro { 72074c3cbe3SAl Viro struct list_head cursor, barrier; 72174c3cbe3SAl Viro int failed = 0; 7222096f759SAl Viro struct path path1, path2; 72374c3cbe3SAl Viro struct vfsmount *tagged; 72474c3cbe3SAl Viro int err; 72574c3cbe3SAl Viro 7262096f759SAl Viro err = kern_path(new, 0, &path2); 72774c3cbe3SAl Viro if (err) 72874c3cbe3SAl Viro return err; 7292096f759SAl Viro tagged = collect_mounts(&path2); 7302096f759SAl Viro path_put(&path2); 731be34d1a3SDavid Howells if (IS_ERR(tagged)) 732be34d1a3SDavid Howells return PTR_ERR(tagged); 73374c3cbe3SAl Viro 7342096f759SAl Viro err = kern_path(old, 0, &path1); 73574c3cbe3SAl Viro if (err) { 73674c3cbe3SAl Viro drop_collected_mounts(tagged); 73774c3cbe3SAl Viro return err; 73874c3cbe3SAl Viro } 73974c3cbe3SAl Viro 74074c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 74174c3cbe3SAl Viro list_add(&barrier, &tree_list); 74274c3cbe3SAl Viro list_add(&cursor, &barrier); 74374c3cbe3SAl Viro 74474c3cbe3SAl Viro while (cursor.next != &tree_list) { 74574c3cbe3SAl Viro struct audit_tree *tree; 7462096f759SAl Viro int good_one = 0; 74774c3cbe3SAl Viro 74874c3cbe3SAl Viro tree = container_of(cursor.next, struct audit_tree, list); 74974c3cbe3SAl Viro get_tree(tree); 75074c3cbe3SAl Viro list_del(&cursor); 75174c3cbe3SAl Viro list_add(&cursor, &tree->list); 75274c3cbe3SAl Viro mutex_unlock(&audit_filter_mutex); 75374c3cbe3SAl Viro 7542096f759SAl Viro err = kern_path(tree->pathname, 0, &path2); 7552096f759SAl Viro if (!err) { 7562096f759SAl Viro good_one = path_is_under(&path1, &path2); 7572096f759SAl Viro path_put(&path2); 75874c3cbe3SAl Viro } 75974c3cbe3SAl Viro 7602096f759SAl Viro if (!good_one) { 76174c3cbe3SAl Viro put_tree(tree); 76274c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 76374c3cbe3SAl Viro continue; 76474c3cbe3SAl Viro } 76574c3cbe3SAl Viro 7661f707137SAl Viro failed = iterate_mounts(tag_mount, tree, tagged); 76774c3cbe3SAl Viro if (failed) { 76874c3cbe3SAl Viro put_tree(tree); 76974c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 77074c3cbe3SAl Viro break; 77174c3cbe3SAl Viro } 77274c3cbe3SAl Viro 77374c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 77474c3cbe3SAl Viro spin_lock(&hash_lock); 77574c3cbe3SAl Viro if (!tree->goner) { 77674c3cbe3SAl Viro list_del(&tree->list); 77774c3cbe3SAl Viro list_add(&tree->list, &tree_list); 77874c3cbe3SAl Viro } 77974c3cbe3SAl Viro spin_unlock(&hash_lock); 78074c3cbe3SAl Viro put_tree(tree); 78174c3cbe3SAl Viro } 78274c3cbe3SAl Viro 78374c3cbe3SAl Viro while (barrier.prev != &tree_list) { 78474c3cbe3SAl Viro struct audit_tree *tree; 78574c3cbe3SAl Viro 78674c3cbe3SAl Viro tree = container_of(barrier.prev, struct audit_tree, list); 78774c3cbe3SAl Viro get_tree(tree); 78874c3cbe3SAl Viro list_del(&tree->list); 78974c3cbe3SAl Viro list_add(&tree->list, &barrier); 79074c3cbe3SAl Viro mutex_unlock(&audit_filter_mutex); 79174c3cbe3SAl Viro 79274c3cbe3SAl Viro if (!failed) { 79374c3cbe3SAl Viro struct node *node; 79474c3cbe3SAl Viro spin_lock(&hash_lock); 79574c3cbe3SAl Viro list_for_each_entry(node, &tree->chunks, list) 79674c3cbe3SAl Viro node->index &= ~(1U<<31); 79774c3cbe3SAl Viro spin_unlock(&hash_lock); 79874c3cbe3SAl Viro } else { 79974c3cbe3SAl Viro trim_marked(tree); 80074c3cbe3SAl Viro } 80174c3cbe3SAl Viro 80274c3cbe3SAl Viro put_tree(tree); 80374c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 80474c3cbe3SAl Viro } 80574c3cbe3SAl Viro list_del(&barrier); 80674c3cbe3SAl Viro list_del(&cursor); 80774c3cbe3SAl Viro mutex_unlock(&audit_filter_mutex); 8082096f759SAl Viro path_put(&path1); 80974c3cbe3SAl Viro drop_collected_mounts(tagged); 81074c3cbe3SAl Viro return failed; 81174c3cbe3SAl Viro } 81274c3cbe3SAl Viro 81374c3cbe3SAl Viro /* 81474c3cbe3SAl Viro * That gets run when evict_chunk() ends up needing to kill audit_tree. 815916d7576SAl Viro * Runs from a separate thread. 81674c3cbe3SAl Viro */ 817916d7576SAl Viro static int prune_tree_thread(void *unused) 81874c3cbe3SAl Viro { 819916d7576SAl Viro mutex_lock(&audit_cmd_mutex); 82074c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 82174c3cbe3SAl Viro 82274c3cbe3SAl Viro while (!list_empty(&prune_list)) { 82374c3cbe3SAl Viro struct audit_tree *victim; 82474c3cbe3SAl Viro 82574c3cbe3SAl Viro victim = list_entry(prune_list.next, struct audit_tree, list); 82674c3cbe3SAl Viro list_del_init(&victim->list); 82774c3cbe3SAl Viro 82874c3cbe3SAl Viro mutex_unlock(&audit_filter_mutex); 82974c3cbe3SAl Viro 83074c3cbe3SAl Viro prune_one(victim); 83174c3cbe3SAl Viro 83274c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 83374c3cbe3SAl Viro } 83474c3cbe3SAl Viro 83574c3cbe3SAl Viro mutex_unlock(&audit_filter_mutex); 836916d7576SAl Viro mutex_unlock(&audit_cmd_mutex); 837916d7576SAl Viro return 0; 838916d7576SAl Viro } 839916d7576SAl Viro 840916d7576SAl Viro static void audit_schedule_prune(void) 841916d7576SAl Viro { 842916d7576SAl Viro kthread_run(prune_tree_thread, NULL, "audit_prune_tree"); 843916d7576SAl Viro } 844916d7576SAl Viro 845916d7576SAl Viro /* 846916d7576SAl Viro * ... and that one is done if evict_chunk() decides to delay until the end 847916d7576SAl Viro * of syscall. Runs synchronously. 848916d7576SAl Viro */ 849916d7576SAl Viro void audit_kill_trees(struct list_head *list) 850916d7576SAl Viro { 851916d7576SAl Viro mutex_lock(&audit_cmd_mutex); 852916d7576SAl Viro mutex_lock(&audit_filter_mutex); 853916d7576SAl Viro 854916d7576SAl Viro while (!list_empty(list)) { 855916d7576SAl Viro struct audit_tree *victim; 856916d7576SAl Viro 857916d7576SAl Viro victim = list_entry(list->next, struct audit_tree, list); 858916d7576SAl Viro kill_rules(victim); 859916d7576SAl Viro list_del_init(&victim->list); 860916d7576SAl Viro 861916d7576SAl Viro mutex_unlock(&audit_filter_mutex); 862916d7576SAl Viro 863916d7576SAl Viro prune_one(victim); 864916d7576SAl Viro 865916d7576SAl Viro mutex_lock(&audit_filter_mutex); 866916d7576SAl Viro } 867916d7576SAl Viro 868916d7576SAl Viro mutex_unlock(&audit_filter_mutex); 869916d7576SAl Viro mutex_unlock(&audit_cmd_mutex); 87074c3cbe3SAl Viro } 87174c3cbe3SAl Viro 87274c3cbe3SAl Viro /* 87374c3cbe3SAl Viro * Here comes the stuff asynchronous to auditctl operations 87474c3cbe3SAl Viro */ 87574c3cbe3SAl Viro 87674c3cbe3SAl Viro static void evict_chunk(struct audit_chunk *chunk) 87774c3cbe3SAl Viro { 87874c3cbe3SAl Viro struct audit_tree *owner; 879916d7576SAl Viro struct list_head *postponed = audit_killed_trees(); 880916d7576SAl Viro int need_prune = 0; 88174c3cbe3SAl Viro int n; 88274c3cbe3SAl Viro 88374c3cbe3SAl Viro if (chunk->dead) 88474c3cbe3SAl Viro return; 88574c3cbe3SAl Viro 88674c3cbe3SAl Viro chunk->dead = 1; 88774c3cbe3SAl Viro mutex_lock(&audit_filter_mutex); 88874c3cbe3SAl Viro spin_lock(&hash_lock); 88974c3cbe3SAl Viro while (!list_empty(&chunk->trees)) { 89074c3cbe3SAl Viro owner = list_entry(chunk->trees.next, 89174c3cbe3SAl Viro struct audit_tree, same_root); 89274c3cbe3SAl Viro owner->goner = 1; 89374c3cbe3SAl Viro owner->root = NULL; 89474c3cbe3SAl Viro list_del_init(&owner->same_root); 89574c3cbe3SAl Viro spin_unlock(&hash_lock); 896916d7576SAl Viro if (!postponed) { 89774c3cbe3SAl Viro kill_rules(owner); 89874c3cbe3SAl Viro list_move(&owner->list, &prune_list); 899916d7576SAl Viro need_prune = 1; 900916d7576SAl Viro } else { 901916d7576SAl Viro list_move(&owner->list, postponed); 902916d7576SAl Viro } 90374c3cbe3SAl Viro spin_lock(&hash_lock); 90474c3cbe3SAl Viro } 90574c3cbe3SAl Viro list_del_rcu(&chunk->hash); 90674c3cbe3SAl Viro for (n = 0; n < chunk->count; n++) 90774c3cbe3SAl Viro list_del_init(&chunk->owners[n].list); 90874c3cbe3SAl Viro spin_unlock(&hash_lock); 909916d7576SAl Viro if (need_prune) 910916d7576SAl Viro audit_schedule_prune(); 91174c3cbe3SAl Viro mutex_unlock(&audit_filter_mutex); 91274c3cbe3SAl Viro } 91374c3cbe3SAl Viro 9143a9b16b4SEric Paris static int audit_tree_handle_event(struct fsnotify_group *group, 9157053aee2SJan Kara struct inode *to_tell, 916ce8f76fbSEric Paris struct fsnotify_mark *inode_mark, 9177053aee2SJan Kara struct fsnotify_mark *vfsmount_mark, 9187053aee2SJan Kara u32 mask, void *data, int data_type, 91945a22f4cSJan Kara const unsigned char *file_name, u32 cookie) 92074c3cbe3SAl Viro { 92183c4c4b0SJan Kara return 0; 92228a3a7ebSEric Paris } 92374c3cbe3SAl Viro 924e61ce867SEric Paris static void audit_tree_freeing_mark(struct fsnotify_mark *entry, struct fsnotify_group *group) 92528a3a7ebSEric Paris { 92628a3a7ebSEric Paris struct audit_chunk *chunk = container_of(entry, struct audit_chunk, mark); 92728a3a7ebSEric Paris 92874c3cbe3SAl Viro evict_chunk(chunk); 929b3e8692bSMiklos Szeredi 930b3e8692bSMiklos Szeredi /* 931b3e8692bSMiklos Szeredi * We are guaranteed to have at least one reference to the mark from 932b3e8692bSMiklos Szeredi * either the inode or the caller of fsnotify_destroy_mark(). 933b3e8692bSMiklos Szeredi */ 934b3e8692bSMiklos Szeredi BUG_ON(atomic_read(&entry->refcnt) < 1); 93574c3cbe3SAl Viro } 93674c3cbe3SAl Viro 93728a3a7ebSEric Paris static const struct fsnotify_ops audit_tree_ops = { 93828a3a7ebSEric Paris .handle_event = audit_tree_handle_event, 93928a3a7ebSEric Paris .freeing_mark = audit_tree_freeing_mark, 94074c3cbe3SAl Viro }; 94174c3cbe3SAl Viro 94274c3cbe3SAl Viro static int __init audit_tree_init(void) 94374c3cbe3SAl Viro { 94474c3cbe3SAl Viro int i; 94574c3cbe3SAl Viro 9460d2e2a1dSEric Paris audit_tree_group = fsnotify_alloc_group(&audit_tree_ops); 94728a3a7ebSEric Paris if (IS_ERR(audit_tree_group)) 94828a3a7ebSEric Paris audit_panic("cannot initialize fsnotify group for rectree watches"); 94974c3cbe3SAl Viro 95074c3cbe3SAl Viro for (i = 0; i < HASH_SIZE; i++) 95174c3cbe3SAl Viro INIT_LIST_HEAD(&chunk_hash_heads[i]); 95274c3cbe3SAl Viro 95374c3cbe3SAl Viro return 0; 95474c3cbe3SAl Viro } 95574c3cbe3SAl Viro __initcall(audit_tree_init); 956