diff options
Diffstat (limited to 'kernel/audit_tree.c')
| -rw-r--r-- | kernel/audit_tree.c | 504 |
1 files changed, 278 insertions, 226 deletions
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 9ef5e0aacc3..135944a7b28 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -1,7 +1,9 @@ #include "audit.h" -#include <linux/inotify.h> +#include <linux/fsnotify_backend.h> #include <linux/namei.h> #include <linux/mount.h> +#include <linux/kthread.h> +#include <linux/slab.h> struct audit_tree; struct audit_chunk; @@ -20,10 +22,11 @@ struct audit_tree { struct audit_chunk { struct list_head hash; - struct inotify_watch watch; + struct fsnotify_mark mark; struct list_head trees; /* with root here */ int dead; int count; + atomic_long_t refs; struct rcu_head head; struct node { struct list_head list; @@ -56,7 +59,8 @@ static LIST_HEAD(prune_list); * tree is refcounted; one reference for "some rules on rules_list refer to * it", one for each chunk with pointer to it. * - * chunk is refcounted by embedded inotify_watch. + * chunk is refcounted by embedded fsnotify_mark + .refs (non-zero refcount + * of watch contributes 1 to .refs). * * 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 @@ -64,7 +68,7 @@ static LIST_HEAD(prune_list); * that makes a difference. Some. */ -static struct inotify_handle *rtree_ih; +static struct fsnotify_group *audit_tree_group; static struct audit_tree *alloc_tree(const char *s) { @@ -89,16 +93,10 @@ static inline void get_tree(struct audit_tree *tree) atomic_inc(&tree->count); } -static void __put_tree(struct rcu_head *rcu) -{ - struct audit_tree *tree = container_of(rcu, struct audit_tree, head); - kfree(tree); -} - static inline void put_tree(struct audit_tree *tree) { if (atomic_dec_and_test(&tree->count)) - call_rcu(&tree->head, __put_tree); + kfree_rcu(tree, head); } /* to avoid bringing the entire thing in audit.h */ @@ -107,6 +105,35 @@ const char *audit_tree_path(struct audit_tree *tree) return tree->pathname; } +static void free_chunk(struct audit_chunk *chunk) +{ + int i; + + for (i = 0; i < chunk->count; i++) { + if (chunk->owners[i].owner) + put_tree(chunk->owners[i].owner); + } + kfree(chunk); +} + +void audit_put_chunk(struct audit_chunk *chunk) +{ + if (atomic_long_dec_and_test(&chunk->refs)) + free_chunk(chunk); +} + +static void __put_chunk(struct rcu_head *rcu) +{ + struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head); + audit_put_chunk(chunk); +} + +static void audit_tree_destroy_watch(struct fsnotify_mark *entry) +{ + 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; @@ -121,36 +148,15 @@ static struct audit_chunk *alloc_chunk(int count) 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; } - inotify_init_watch(&chunk->watch); + fsnotify_init_mark(&chunk->mark, audit_tree_destroy_watch); return chunk; } -static void __free_chunk(struct rcu_head *rcu) -{ - struct audit_chunk *chunk = container_of(rcu, struct audit_chunk, head); - int i; - - for (i = 0; i < chunk->count; i++) { - if (chunk->owners[i].owner) - put_tree(chunk->owners[i].owner); - } - kfree(chunk); -} - -static inline void free_chunk(struct audit_chunk *chunk) -{ - call_rcu(&chunk->head, __free_chunk); -} - -void audit_put_chunk(struct audit_chunk *chunk) -{ - put_inotify_watch(&chunk->watch); -} - enum {HASH_SIZE = 128}; static struct list_head chunk_hash_heads[HASH_SIZE]; static __cacheline_aligned_in_smp DEFINE_SPINLOCK(hash_lock); @@ -161,10 +167,15 @@ static inline struct list_head *chunk_hash(const struct inode *inode) return chunk_hash_heads + n % HASH_SIZE; } -/* hash_lock is held by caller */ +/* hash_lock & entry->lock is held by caller */ static void insert_hash(struct audit_chunk *chunk) { - struct list_head *list = chunk_hash(chunk->watch.inode); + struct fsnotify_mark *entry = &chunk->mark; + struct list_head *list; + + if (!entry->i.inode) + return; + list = chunk_hash(entry->i.inode); list_add_rcu(&chunk->hash, list); } @@ -172,12 +183,12 @@ static void insert_hash(struct audit_chunk *chunk) struct audit_chunk *audit_tree_lookup(const struct inode *inode) { struct list_head *list = chunk_hash(inode); - struct list_head *pos; + struct audit_chunk *p; - list_for_each_rcu(pos, list) { - struct audit_chunk *p = container_of(pos, struct audit_chunk, hash); - if (p->watch.inode == inode) { - get_inotify_watch(&p->watch); + list_for_each_entry_rcu(p, list, hash) { + /* mark.inode may have gone NULL, but who cares? */ + if (p->mark.i.inode == inode) { + atomic_long_inc(&p->refs); return p; } } @@ -195,17 +206,35 @@ int audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree) /* tagging and untagging inodes with trees */ -static void untag_chunk(struct audit_chunk *chunk, struct node *p) +static struct audit_chunk *find_chunk(struct node *p) { - struct audit_chunk *new; + int index = p->index & ~(1U<<31); + p -= index; + return container_of(p, struct audit_chunk, owners[0]); +} + +static void untag_chunk(struct node *p) +{ + struct audit_chunk *chunk = find_chunk(p); + struct fsnotify_mark *entry = &chunk->mark; + struct audit_chunk *new = NULL; struct audit_tree *owner; int size = chunk->count - 1; int i, j; - mutex_lock(&chunk->watch.inode->inotify_mutex); - if (chunk->dead) { - mutex_unlock(&chunk->watch.inode->inotify_mutex); - return; + fsnotify_get_mark(entry); + + spin_unlock(&hash_lock); + + if (size) + new = alloc_chunk(size); + + spin_lock(&entry->lock); + if (chunk->dead || !entry->i.inode) { + spin_unlock(&entry->lock); + if (new) + free_chunk(new); + goto out; } owner = p->owner; @@ -219,17 +248,17 @@ static void untag_chunk(struct audit_chunk *chunk, struct node *p) list_del_init(&p->list); list_del_rcu(&chunk->hash); spin_unlock(&hash_lock); - inotify_evict_watch(&chunk->watch); - mutex_unlock(&chunk->watch.inode->inotify_mutex); - put_inotify_watch(&chunk->watch); - return; + spin_unlock(&entry->lock); + fsnotify_destroy_mark(entry, audit_tree_group); + goto out; } - new = alloc_chunk(size); if (!new) goto Fallback; - if (inotify_clone_watch(&chunk->watch, &new->watch) < 0) { - free_chunk(new); + + fsnotify_duplicate_mark(&new->mark, entry); + if (fsnotify_add_mark(&new->mark, new->mark.group, new->mark.i.inode, NULL, 1)) { + fsnotify_put_mark(&new->mark); goto Fallback; } @@ -241,7 +270,7 @@ static void untag_chunk(struct audit_chunk *chunk, struct node *p) owner->root = NULL; } - for (i = j = 0; i < size; i++, j++) { + for (i = j = 0; j <= size; i++, j++) { struct audit_tree *s; if (&chunk->owners[j] == p) { list_del_init(&p->list); @@ -254,17 +283,17 @@ static void untag_chunk(struct audit_chunk *chunk, struct node *p) if (!s) /* result of earlier fallback */ continue; get_tree(s); - list_replace_init(&chunk->owners[i].list, &new->owners[j].list); + list_replace_init(&chunk->owners[j].list, &new->owners[i].list); } list_replace_rcu(&chunk->hash, &new->hash); list_for_each_entry(owner, &new->trees, same_root) owner->root = new; spin_unlock(&hash_lock); - inotify_evict_watch(&chunk->watch); - mutex_unlock(&chunk->watch.inode->inotify_mutex); - put_inotify_watch(&chunk->watch); - return; + spin_unlock(&entry->lock); + fsnotify_destroy_mark(entry, audit_tree_group); + fsnotify_put_mark(&new->mark); /* drop initial reference */ + goto out; Fallback: // do the best we can @@ -277,28 +306,33 @@ Fallback: p->owner = NULL; put_tree(owner); spin_unlock(&hash_lock); - mutex_unlock(&chunk->watch.inode->inotify_mutex); + spin_unlock(&entry->lock); +out: + fsnotify_put_mark(entry); + spin_lock(&hash_lock); } static int create_chunk(struct inode *inode, struct audit_tree *tree) { + struct fsnotify_mark *entry; struct audit_chunk *chunk = alloc_chunk(1); if (!chunk) return -ENOMEM; - if (inotify_add_watch(rtree_ih, &chunk->watch, inode, IN_IGNORED | IN_DELETE_SELF) < 0) { - free_chunk(chunk); + entry = &chunk->mark; + if (fsnotify_add_mark(entry, audit_tree_group, inode, NULL, 0)) { + fsnotify_put_mark(entry); return -ENOSPC; } - mutex_lock(&inode->inotify_mutex); + spin_lock(&entry->lock); spin_lock(&hash_lock); if (tree->goner) { spin_unlock(&hash_lock); chunk->dead = 1; - inotify_evict_watch(&chunk->watch); - mutex_unlock(&inode->inotify_mutex); - put_inotify_watch(&chunk->watch); + spin_unlock(&entry->lock); + fsnotify_destroy_mark(entry, audit_tree_group); + fsnotify_put_mark(entry); return 0; } chunk->owners[0].index = (1U << 31); @@ -311,52 +345,77 @@ static int create_chunk(struct inode *inode, struct audit_tree *tree) } insert_hash(chunk); spin_unlock(&hash_lock); - mutex_unlock(&inode->inotify_mutex); + spin_unlock(&entry->lock); + fsnotify_put_mark(entry); /* drop initial reference */ return 0; } /* the first tagged inode becomes root of tree */ static int tag_chunk(struct inode *inode, struct audit_tree *tree) { - struct inotify_watch *watch; + struct fsnotify_mark *old_entry, *chunk_entry; struct audit_tree *owner; struct audit_chunk *chunk, *old; struct node *p; int n; - if (inotify_find_watch(rtree_ih, inode, &watch) < 0) + old_entry = fsnotify_find_inode_mark(audit_tree_group, inode); + if (!old_entry) return create_chunk(inode, tree); - old = container_of(watch, struct audit_chunk, watch); + old = container_of(old_entry, struct audit_chunk, mark); /* 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); - put_inotify_watch(watch); + fsnotify_put_mark(old_entry); return 0; } } spin_unlock(&hash_lock); chunk = alloc_chunk(old->count + 1); - if (!chunk) + if (!chunk) { + fsnotify_put_mark(old_entry); return -ENOMEM; + } + + chunk_entry = &chunk->mark; - mutex_lock(&inode->inotify_mutex); - if (inotify_clone_watch(&old->watch, &chunk->watch) < 0) { - mutex_unlock(&inode->inotify_mutex); + spin_lock(&old_entry->lock); + if (!old_entry->i.inode) { + /* old_entry is being shot, lets just lie */ + spin_unlock(&old_entry->lock); + fsnotify_put_mark(old_entry); free_chunk(chunk); + return -ENOENT; + } + + fsnotify_duplicate_mark(chunk_entry, old_entry); + if (fsnotify_add_mark(chunk_entry, chunk_entry->group, chunk_entry->i.inode, NULL, 1)) { + spin_unlock(&old_entry->lock); + fsnotify_put_mark(chunk_entry); + fsnotify_put_mark(old_entry); return -ENOSPC; } + + /* 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); spin_lock(&hash_lock); + + /* we now hold old_entry->lock, chunk_entry->lock, and hash_lock */ if (tree->goner) { spin_unlock(&hash_lock); chunk->dead = 1; - inotify_evict_watch(&chunk->watch); - mutex_unlock(&inode->inotify_mutex); - put_inotify_watch(&chunk->watch); + spin_unlock(&chunk_entry->lock); + spin_unlock(&old_entry->lock); + + fsnotify_destroy_mark(chunk_entry, audit_tree_group); + + fsnotify_put_mark(chunk_entry); + fsnotify_put_mark(old_entry); return 0; } list_replace_init(&old->trees, &chunk->trees); @@ -382,24 +441,34 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree) list_add(&tree->same_root, &chunk->trees); } spin_unlock(&hash_lock); - inotify_evict_watch(&old->watch); - mutex_unlock(&inode->inotify_mutex); - put_inotify_watch(&old->watch); + spin_unlock(&chunk_entry->lock); + spin_unlock(&old_entry->lock); + fsnotify_destroy_mark(old_entry, audit_tree_group); + fsnotify_put_mark(chunk_entry); /* drop initial reference */ + fsnotify_put_mark(old_entry); /* pair to fsnotify_find mark_entry */ return 0; } -static struct audit_chunk *find_chunk(struct node *p) +static void audit_log_remove_rule(struct audit_krule *rule) { - int index = p->index & ~(1U<<31); - p -= index; - return container_of(p, struct audit_chunk, owners[0]); + struct audit_buffer *ab; + + ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); + if (unlikely(!ab)) + return; + audit_log_format(ab, "op="); + audit_log_string(ab, "remove rule"); + audit_log_format(ab, " dir="); + audit_log_untrustedstring(ab, rule->tree->pathname); + audit_log_key(ab, rule->filterkey); + audit_log_format(ab, " list=%d res=1", rule->listnr); + audit_log_end(ab); } 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); @@ -407,18 +476,10 @@ static void kill_rules(struct audit_tree *tree) list_del_init(&rule->rlist); if (rule->tree) { /* not a half-baked one */ - ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); - audit_log_format(ab, "op=remove rule dir="); - audit_log_untrustedstring(ab, rule->tree->pathname); - if (rule->filterkey) { - audit_log_format(ab, " key="); - audit_log_untrustedstring(ab, rule->filterkey); - } else - audit_log_format(ab, " key=(null)"); - audit_log_format(ab, " list=%d res=1", rule->listnr); - audit_log_end(ab); + audit_log_remove_rule(rule); rule->tree = NULL; list_del_rcu(&entry->list); + list_del(&entry->rule.list); call_rcu(&entry->rcu, audit_free_rule_rcu); } } @@ -432,17 +493,10 @@ static void prune_one(struct audit_tree *victim) spin_lock(&hash_lock); while (!list_empty(&victim->chunks)) { struct node *p; - struct audit_chunk *chunk; p = list_entry(victim->chunks.next, struct node, list); - chunk = find_chunk(p); - get_inotify_watch(&chunk->watch); - spin_unlock(&hash_lock); - untag_chunk(chunk, p); - - put_inotify_watch(&chunk->watch); - spin_lock(&hash_lock); + untag_chunk(p); } spin_unlock(&hash_lock); put_tree(victim); @@ -470,7 +524,6 @@ static void trim_marked(struct audit_tree *tree) while (!list_empty(&tree->chunks)) { struct node *node; - struct audit_chunk *chunk; node = list_entry(tree->chunks.next, struct node, list); @@ -478,14 +531,7 @@ static void trim_marked(struct audit_tree *tree) if (!(node->index & (1U<<31))) break; - chunk = find_chunk(node); - get_inotify_watch(&chunk->watch); - spin_unlock(&hash_lock); - - untag_chunk(chunk, node); - - put_inotify_watch(&chunk->watch); - spin_lock(&hash_lock); + untag_chunk(node); } if (!tree->root && !tree->goner) { tree->goner = 1; @@ -500,6 +546,8 @@ static void trim_marked(struct audit_tree *tree) } } +static void audit_schedule_prune(void); + /* called with audit_filter_mutex */ int audit_remove_tree_rule(struct audit_krule *rule) { @@ -525,6 +573,11 @@ int audit_remove_tree_rule(struct audit_krule *rule) return 0; } +static int compare_root(struct vfsmount *mnt, void *arg) +{ + return mnt->mnt_root->d_inode == arg; +} + void audit_trim_trees(void) { struct list_head cursor; @@ -533,10 +586,9 @@ void audit_trim_trees(void) list_add(&cursor, &tree_list); while (cursor.next != &tree_list) { struct audit_tree *tree; - struct nameidata nd; + struct path path; struct vfsmount *root_mnt; struct node *node; - struct list_head list; int err; tree = container_of(cursor.next, struct audit_tree, list); @@ -545,63 +597,41 @@ void audit_trim_trees(void) list_add(&cursor, &tree->list); mutex_unlock(&audit_filter_mutex); - err = path_lookup(tree->pathname, 0, &nd); + err = kern_path(tree->pathname, 0, &path); if (err) goto skip_it; - root_mnt = collect_mounts(nd.path.mnt, nd.path.dentry); - path_put(&nd.path); - if (!root_mnt) + root_mnt = collect_mounts(&path); + path_put(&path); + if (IS_ERR(root_mnt)) goto skip_it; - list_add_tail(&list, &root_mnt->mnt_list); spin_lock(&hash_lock); list_for_each_entry(node, &tree->chunks, list) { struct audit_chunk *chunk = find_chunk(node); - struct inode *inode = chunk->watch.inode; - struct vfsmount *mnt; + /* this could be NULL if the watch is dying else where... */ + struct inode *inode = chunk->mark.i.inode; node->index |= 1U<<31; - list_for_each_entry(mnt, &list, mnt_list) { - if (mnt->mnt_root->d_inode == inode) { - node->index &= ~(1U<<31); - break; - } - } + if (iterate_mounts(compare_root, inode, root_mnt)) + node->index &= ~(1U<<31); } spin_unlock(&hash_lock); trim_marked(tree); - put_tree(tree); - list_del_init(&list); drop_collected_mounts(root_mnt); skip_it: + put_tree(tree); mutex_lock(&audit_filter_mutex); } list_del(&cursor); mutex_unlock(&audit_filter_mutex); } -static int is_under(struct vfsmount *mnt, struct dentry *dentry, - struct nameidata *nd) -{ - if (mnt != nd->path.mnt) { - for (;;) { - if (mnt->mnt_parent == mnt) - return 0; - if (mnt->mnt_parent == nd->path.mnt) - break; - mnt = mnt->mnt_parent; - } - dentry = mnt->mnt_mountpoint; - } - return is_subdir(dentry, nd->path.dentry); -} - int audit_make_tree(struct audit_krule *rule, char *pathname, u32 op) { if (pathname[0] != '/' || rule->listnr != AUDIT_FILTER_EXIT || - op & ~AUDIT_EQUAL || + op != Audit_equal || rule->inode_f || rule->watch || rule->tree) return -EINVAL; rule->tree = alloc_tree(pathname); @@ -615,15 +645,20 @@ void audit_put_tree(struct audit_tree *tree) put_tree(tree); } +static int tag_mount(struct vfsmount *mnt, void *arg) +{ + return tag_chunk(mnt->mnt_root->d_inode, arg); +} + /* called with audit_filter_mutex */ int audit_add_tree_rule(struct audit_krule *rule) { struct audit_tree *seed = rule->tree, *tree; - struct nameidata nd; - struct vfsmount *mnt, *p; - struct list_head list; + struct path path; + struct vfsmount *mnt; int err; + rule->tree = NULL; list_for_each_entry(tree, &tree_list, list) { if (!strcmp(seed->pathname, tree->pathname)) { put_tree(seed); @@ -638,25 +673,18 @@ int audit_add_tree_rule(struct audit_krule *rule) /* do not set rule->tree yet */ mutex_unlock(&audit_filter_mutex); - err = path_lookup(tree->pathname, 0, &nd); + err = kern_path(tree->pathname, 0, &path); if (err) goto Err; - mnt = collect_mounts(nd.path.mnt, nd.path.dentry); - path_put(&nd.path); - if (!mnt) { - err = -ENOMEM; + mnt = collect_mounts(&path); + path_put(&path); + if (IS_ERR(mnt)) { + err = PTR_ERR(mnt); goto Err; } - list_add_tail(&list, &mnt->mnt_list); get_tree(tree); - list_for_each_entry(p, &list, mnt_list) { - err = tag_chunk(p->mnt_root->d_inode, tree); - if (err) - break; - } - - list_del(&list); + err = iterate_mounts(tag_mount, tree, mnt); drop_collected_mounts(mnt); if (!err) { @@ -691,34 +719,23 @@ int audit_tag_tree(char *old, char *new) { struct list_head cursor, barrier; int failed = 0; - struct nameidata nd; + struct path path1, path2; struct vfsmount *tagged; - struct list_head list; - struct vfsmount *mnt; - struct dentry *dentry; int err; - err = path_lookup(new, 0, &nd); + err = kern_path(new, 0, &path2); if (err) return err; - tagged = collect_mounts(nd.path.mnt, nd.path.dentry); - path_put(&nd.path); - if (!tagged) - return -ENOMEM; + tagged = collect_mounts(&path2); + path_put(&path2); + if (IS_ERR(tagged)) + return PTR_ERR(tagged); - err = path_lookup(old, 0, &nd); + err = kern_path(old, 0, &path1); if (err) { drop_collected_mounts(tagged); return err; } - mnt = mntget(nd.path.mnt); - dentry = dget(nd.path.dentry); - path_put(&nd.path); - - if (dentry == tagged->mnt_root && dentry == mnt->mnt_root) - follow_up(&mnt, &dentry); - - list_add_tail(&list, &tagged->mnt_list); mutex_lock(&audit_filter_mutex); list_add(&barrier, &tree_list); @@ -726,7 +743,7 @@ int audit_tag_tree(char *old, char *new) while (cursor.next != &tree_list) { struct audit_tree *tree; - struct vfsmount *p; + int good_one = 0; tree = container_of(cursor.next, struct audit_tree, list); get_tree(tree); @@ -734,30 +751,19 @@ int audit_tag_tree(char *old, char *new) list_add(&cursor, &tree->list); mutex_unlock(&audit_filter_mutex); - err = path_lookup(tree->pathname, 0, &nd); - if (err) { - put_tree(tree); - mutex_lock(&audit_filter_mutex); - continue; + err = kern_path(tree->pathname, 0, &path2); + if (!err) { + good_one = path_is_under(&path1, &path2); + path_put(&path2); } - spin_lock(&vfsmount_lock); - if (!is_under(mnt, dentry, &nd)) { - spin_unlock(&vfsmount_lock); - path_put(&nd.path); + if (!good_one) { put_tree(tree); mutex_lock(&audit_filter_mutex); continue; } - spin_unlock(&vfsmount_lock); - path_put(&nd.path); - - list_for_each_entry(p, &list, mnt_list) { - failed = tag_chunk(p->mnt_root->d_inode, tree); - if (failed) - break; - } + failed = iterate_mounts(tag_mount, tree, tagged); if (failed) { put_tree(tree); mutex_lock(&audit_filter_mutex); @@ -798,20 +804,19 @@ int audit_tag_tree(char *old, char *new) } list_del(&barrier); list_del(&cursor); - list_del(&list); mutex_unlock(&audit_filter_mutex); - dput(dentry); - mntput(mnt); + path_put(&path1); drop_collected_mounts(tagged); return failed; } /* * That gets run when evict_chunk() ends up needing to kill audit_tree. - * Runs from a separate thread, with audit_cmd_mutex held. + * Runs from a separate thread. */ -void audit_prune_trees(void) +static int prune_tree_thread(void *unused) { + mutex_lock(&audit_cmd_mutex); mutex_lock(&audit_filter_mutex); while (!list_empty(&prune_list)) { @@ -828,16 +833,51 @@ void audit_prune_trees(void) } mutex_unlock(&audit_filter_mutex); + 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); } /* * Here comes the stuff asynchronous to auditctl operations */ -/* inode->inotify_mutex is locked */ static void evict_chunk(struct audit_chunk *chunk) { struct audit_tree *owner; + struct list_head *postponed = audit_killed_trees(); + int need_prune = 0; int n; if (chunk->dead) @@ -853,47 +893,59 @@ static void evict_chunk(struct audit_chunk *chunk) owner->root = NULL; list_del_init(&owner->same_root); spin_unlock(&hash_lock); - kill_rules(owner); - list_move(&owner->list, &prune_list); - audit_schedule_prune(); + if (!postponed) { + kill_rules(owner); + list_move(&owner->list, &prune_list); + need_prune = 1; + } else { + list_move(&owner->list, postponed); + } 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); + if (need_prune) + audit_schedule_prune(); mutex_unlock(&audit_filter_mutex); } -static void handle_event(struct inotify_watch *watch, u32 wd, u32 mask, - u32 cookie, const char *dname, struct inode *inode) +static int audit_tree_handle_event(struct fsnotify_group *group, + struct inode *to_tell, + struct fsnotify_mark *inode_mark, + struct fsnotify_mark *vfsmount_mark, + u32 mask, void *data, int data_type, + const unsigned char *file_name, u32 cookie) { - struct audit_chunk *chunk = container_of(watch, struct audit_chunk, watch); - - if (mask & IN_IGNORED) { - evict_chunk(chunk); - put_inotify_watch(watch); - } + return 0; } -static void destroy_watch(struct inotify_watch *watch) +static void audit_tree_freeing_mark(struct fsnotify_mark *entry, struct fsnotify_group *group) { - struct audit_chunk *chunk = container_of(watch, struct audit_chunk, watch); - free_chunk(chunk); + struct audit_chunk *chunk = container_of(entry, struct audit_chunk, mark); + + evict_chunk(chunk); + + /* + * We are guaranteed to have at least one reference to the mark from + * either the inode or the caller of fsnotify_destroy_mark(). + */ + BUG_ON(atomic_read(&entry->refcnt) < 1); } -static const struct inotify_operations rtree_inotify_ops = { - .handle_event = handle_event, - .destroy_watch = destroy_watch, +static const struct fsnotify_ops audit_tree_ops = { + .handle_event = audit_tree_handle_event, + .freeing_mark = audit_tree_freeing_mark, }; static int __init audit_tree_init(void) { int i; - rtree_ih = inotify_init(&rtree_inotify_ops); - if (IS_ERR(rtree_ih)) - audit_panic("cannot initialize inotify handle for rectree watches"); + audit_tree_group = fsnotify_alloc_group(&audit_tree_ops); + if (IS_ERR(audit_tree_group)) + audit_panic("cannot initialize fsnotify group for rectree watches"); for (i = 0; i < HASH_SIZE; i++) INIT_LIST_HEAD(&chunk_hash_heads[i]); |
