From cfcad62c74abfef83762dc05a556d21bdf3980a2 Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Thu, 11 Jun 2009 14:31:36 -0400 Subject: audit: seperate audit inode watches into a subfile In preparation for converting audit to use fsnotify instead of inotify we seperate the inode watching code into it's own file. This is similar to how the audit tree watching code is already seperated into audit_tree.c Signed-off-by: Eric Paris --- kernel/audit.h | 39 ++++++++++++++++++++------------------- 1 file changed, 20 insertions(+), 19 deletions(-) (limited to 'kernel/audit.h') diff --git a/kernel/audit.h b/kernel/audit.h index 16f18cac661..704d5b01d9f 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -53,18 +53,7 @@ enum audit_state { }; /* Rule lists */ -struct audit_parent; - -struct audit_watch { - atomic_t count; /* reference count */ - char *path; /* insertion path */ - dev_t dev; /* associated superblock device */ - unsigned long ino; /* associated inode number */ - struct audit_parent *parent; /* associated parent */ - struct list_head wlist; /* entry in parent->watches list */ - struct list_head rules; /* associated rules */ -}; - +struct audit_watch; struct audit_tree; struct audit_chunk; @@ -108,19 +97,31 @@ struct audit_netlink_list { int audit_send_list(void *); -struct inotify_watch; -/* Inotify handle */ -extern struct inotify_handle *audit_ih; - -extern void audit_free_parent(struct inotify_watch *); -extern void audit_handle_ievent(struct inotify_watch *, u32, u32, u32, - const char *, struct inode *); extern int selinux_audit_rule_update(void); extern struct mutex audit_filter_mutex; extern void audit_free_rule_rcu(struct rcu_head *); extern struct list_head audit_filter_list[]; +/* audit watch functions */ +extern unsigned long audit_watch_inode(struct audit_watch *watch); +extern dev_t audit_watch_dev(struct audit_watch *watch); +extern void audit_put_watch(struct audit_watch *watch); +extern void audit_get_watch(struct audit_watch *watch); +extern int audit_to_watch(struct audit_krule *krule, char *path, int len, u32 op); +extern int audit_get_nd(char *path, struct nameidata **ndp, struct nameidata **ndw); +extern void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw); +extern int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp, + struct nameidata *ndw); +extern void audit_remove_watch(struct audit_watch *watch); +extern void audit_remove_watch_rule(struct audit_krule *krule, struct list_head *list); +extern void audit_inotify_unregister(struct list_head *in_list); +extern char *audit_watch_path(struct audit_watch *watch); +extern struct list_head *audit_watch_rules(struct audit_watch *watch); + +extern struct audit_entry *audit_dupe_rule(struct audit_krule *old, + struct audit_watch *watch); + #ifdef CONFIG_AUDIT_TREE extern struct audit_chunk *audit_tree_lookup(const struct inode *); extern void audit_put_chunk(struct audit_chunk *); -- cgit v1.2.3-70-g09d2 From 35fe4d0b1b12286a81938e9c5fdfaf639ac0ce5b Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Thu, 11 Jun 2009 14:31:36 -0400 Subject: Audit: move audit_get_nd completely into audit_watch audit_get_nd() is only used by audit_watch and could be more cleanly implemented by having the audit watch functions call it when needed rather than making the generic audit rule parsing code deal with those objects. Signed-off-by: Eric Paris --- kernel/audit.h | 5 +---- kernel/audit_watch.c | 27 ++++++++++++++++++++------- kernel/auditfilter.c | 15 ++------------- 3 files changed, 23 insertions(+), 24 deletions(-) (limited to 'kernel/audit.h') diff --git a/kernel/audit.h b/kernel/audit.h index 704d5b01d9f..bb1c0d69db0 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -109,10 +109,7 @@ extern dev_t audit_watch_dev(struct audit_watch *watch); extern void audit_put_watch(struct audit_watch *watch); extern void audit_get_watch(struct audit_watch *watch); extern int audit_to_watch(struct audit_krule *krule, char *path, int len, u32 op); -extern int audit_get_nd(char *path, struct nameidata **ndp, struct nameidata **ndw); -extern void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw); -extern int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp, - struct nameidata *ndw); +extern int audit_add_watch(struct audit_krule *krule); extern void audit_remove_watch(struct audit_watch *watch); extern void audit_remove_watch_rule(struct audit_krule *krule, struct list_head *list); extern void audit_inotify_unregister(struct list_head *in_list); diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index da8be6d39c1..b49ab019fdf 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -345,7 +345,7 @@ void audit_inotify_unregister(struct list_head *in_list) } /* Get path information necessary for adding watches. */ -int audit_get_nd(char *path, struct nameidata **ndp, struct nameidata **ndw) +static int audit_get_nd(char *path, struct nameidata **ndp, struct nameidata **ndw) { struct nameidata *ndparent, *ndwatch; int err; @@ -380,7 +380,7 @@ int audit_get_nd(char *path, struct nameidata **ndp, struct nameidata **ndw) } /* Release resources used for watch path information. */ -void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw) +static void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw) { if (ndp) { path_put(&ndp->path); @@ -426,14 +426,24 @@ static void audit_add_to_parent(struct audit_krule *krule, /* Find a matching watch entry, or add this one. * Caller must hold audit_filter_mutex. */ -int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp, - struct nameidata *ndw) +int audit_add_watch(struct audit_krule *krule) { struct audit_watch *watch = krule->watch; struct inotify_watch *i_watch; struct audit_parent *parent; + struct nameidata *ndp = NULL, *ndw = NULL; int ret = 0; + mutex_unlock(&audit_filter_mutex); + + /* Avoid calling path_lookup under audit_filter_mutex. */ + ret = audit_get_nd(watch->path, &ndp, &ndw); + if (ret) { + /* caller expects mutex locked */ + mutex_lock(&audit_filter_mutex); + goto error; + } + /* update watch filter fields */ if (ndw) { watch->dev = ndw->path.dentry->d_inode->i_sb->s_dev; @@ -445,15 +455,14 @@ int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp, * inotify watch is found, inotify_find_watch() grabs a reference before * returning. */ - mutex_unlock(&audit_filter_mutex); - if (inotify_find_watch(audit_ih, ndp->path.dentry->d_inode, &i_watch) < 0) { parent = audit_init_parent(ndp); if (IS_ERR(parent)) { /* caller expects mutex locked */ mutex_lock(&audit_filter_mutex); - return PTR_ERR(parent); + ret = PTR_ERR(parent); + goto error; } } else parent = container_of(i_watch, struct audit_parent, wdata); @@ -468,7 +477,11 @@ int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp, /* match get in audit_init_parent or inotify_find_watch */ put_inotify_watch(&parent->wdata); + +error: + audit_put_nd(ndp, ndw); /* NULL args OK */ return ret; + } void audit_remove_watch_rule(struct audit_krule *krule, struct list_head *list) diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index 9d4c93437de..21b623595aa 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -864,7 +864,6 @@ static inline int audit_add_rule(struct audit_entry *entry) struct audit_entry *e; struct audit_watch *watch = entry->rule.watch; struct audit_tree *tree = entry->rule.tree; - struct nameidata *ndp = NULL, *ndw = NULL; struct list_head *list; int h, err; #ifdef CONFIG_AUDITSYSCALL @@ -878,8 +877,8 @@ static inline int audit_add_rule(struct audit_entry *entry) mutex_lock(&audit_filter_mutex); e = audit_find_rule(entry, &list); - mutex_unlock(&audit_filter_mutex); if (e) { + mutex_unlock(&audit_filter_mutex); err = -EEXIST; /* normally audit_add_tree_rule() will free it on failure */ if (tree) @@ -887,17 +886,9 @@ static inline int audit_add_rule(struct audit_entry *entry) goto error; } - /* Avoid calling path_lookup under audit_filter_mutex. */ - if (watch) { - err = audit_get_nd(audit_watch_path(watch), &ndp, &ndw); - if (err) - goto error; - } - - mutex_lock(&audit_filter_mutex); if (watch) { /* audit_filter_mutex is dropped and re-taken during this call */ - err = audit_add_watch(&entry->rule, ndp, ndw); + err = audit_add_watch(&entry->rule); if (err) { mutex_unlock(&audit_filter_mutex); goto error; @@ -942,11 +933,9 @@ static inline int audit_add_rule(struct audit_entry *entry) #endif mutex_unlock(&audit_filter_mutex); - audit_put_nd(ndp, ndw); /* NULL args OK */ return 0; error: - audit_put_nd(ndp, ndw); /* NULL args OK */ if (watch) audit_put_watch(watch); /* tmp watch, matches initial get */ return err; -- cgit v1.2.3-70-g09d2 From 916d75761c971b6e630a26bd4ba472e90ac9a4b9 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 24 Jun 2009 00:02:38 -0400 Subject: Fix rule eviction order for AUDIT_DIR If syscall removes the root of subtree being watched, we definitely do not want the rules refering that subtree to be destroyed without the syscall in question having a chance to match them. Signed-off-by: Al Viro --- kernel/audit.c | 17 +--------------- kernel/audit.h | 7 +++++-- kernel/audit_tree.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++----- kernel/auditsc.c | 15 ++++++++++++++ 4 files changed, 72 insertions(+), 23 deletions(-) (limited to 'kernel/audit.h') diff --git a/kernel/audit.c b/kernel/audit.c index 6194c50e203..defc2e6f1e3 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -133,7 +133,7 @@ static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait); static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait); /* Serialize requests from userspace. */ -static DEFINE_MUTEX(audit_cmd_mutex); +DEFINE_MUTEX(audit_cmd_mutex); /* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting * audit records. Since printk uses a 1024 byte buffer, this buffer @@ -505,21 +505,6 @@ int audit_send_list(void *_dest) return 0; } -#ifdef CONFIG_AUDIT_TREE -static int prune_tree_thread(void *unused) -{ - mutex_lock(&audit_cmd_mutex); - audit_prune_trees(); - mutex_unlock(&audit_cmd_mutex); - return 0; -} - -void audit_schedule_prune(void) -{ - kthread_run(prune_tree_thread, NULL, "audit_prune_tree"); -} -#endif - struct sk_buff *audit_make_reply(int pid, int seq, int type, int done, int multi, void *payload, int size) { diff --git a/kernel/audit.h b/kernel/audit.h index bb1c0d69db0..208687be4f3 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -128,10 +128,9 @@ extern int audit_add_tree_rule(struct audit_krule *); extern int audit_remove_tree_rule(struct audit_krule *); extern void audit_trim_trees(void); extern int audit_tag_tree(char *old, char *new); -extern void audit_schedule_prune(void); -extern void audit_prune_trees(void); extern const char *audit_tree_path(struct audit_tree *); extern void audit_put_tree(struct audit_tree *); +extern void audit_kill_trees(struct list_head *); #else #define audit_remove_tree_rule(rule) BUG() #define audit_add_tree_rule(rule) -EINVAL @@ -140,6 +139,7 @@ extern void audit_put_tree(struct audit_tree *); #define audit_put_tree(tree) (void)0 #define audit_tag_tree(old, new) -EINVAL #define audit_tree_path(rule) "" /* never called */ +#define audit_kill_trees(list) BUG() #endif extern char *audit_unpack_string(void **, size_t *, size_t); @@ -158,7 +158,10 @@ static inline int audit_signal_info(int sig, struct task_struct *t) return 0; } extern void audit_filter_inodes(struct task_struct *, struct audit_context *); +extern struct list_head *audit_killed_trees(void); #else #define audit_signal_info(s,t) AUDIT_DISABLED #define audit_filter_inodes(t,c) AUDIT_DISABLED #endif + +extern struct mutex audit_cmd_mutex; diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 3ff0731284a..2451dc6f328 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -2,6 +2,7 @@ #include #include #include +#include struct audit_tree; struct audit_chunk; @@ -517,6 +518,8 @@ 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) { @@ -822,10 +825,11 @@ int audit_tag_tree(char *old, char *new) /* * 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)) { @@ -842,6 +846,40 @@ 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); } /* @@ -852,6 +890,8 @@ void audit_prune_trees(void) 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) @@ -867,15 +907,21 @@ 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); } diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 2de95d1582b..68d3c6a0ecd 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -199,6 +199,7 @@ struct audit_context { struct audit_tree_refs *trees, *first_trees; int tree_count; + struct list_head killed_trees; int type; union { @@ -853,6 +854,7 @@ static inline struct audit_context *audit_alloc_context(enum audit_state state) if (!(context = kmalloc(sizeof(*context), GFP_KERNEL))) return NULL; audit_zero_context(context, state); + INIT_LIST_HEAD(&context->killed_trees); return context; } @@ -1545,6 +1547,8 @@ void audit_free(struct task_struct *tsk) /* that can happen only if we are called from do_exit() */ if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT) audit_log_exit(context, tsk); + if (!list_empty(&context->killed_trees)) + audit_kill_trees(&context->killed_trees); audit_free_context(context); } @@ -1688,6 +1692,9 @@ void audit_syscall_exit(int valid, long return_code) context->in_syscall = 0; context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0; + if (!list_empty(&context->killed_trees)) + audit_kill_trees(&context->killed_trees); + if (context->previous) { struct audit_context *new_context = context->previous; context->previous = NULL; @@ -2521,3 +2528,11 @@ void audit_core_dumps(long signr) audit_log_format(ab, " sig=%ld", signr); audit_log_end(ab); } + +struct list_head *audit_killed_trees(void) +{ + struct audit_context *ctx = current->audit_context; + if (likely(!ctx || !ctx->in_syscall)) + return NULL; + return &ctx->killed_trees; +} -- cgit v1.2.3-70-g09d2