From ae7b8f4108bcffb42173f867ce845268c7202d48 Mon Sep 17 00:00:00 2001 From: Eric Paris Date: Thu, 17 Dec 2009 20:12:04 -0500 Subject: Audit: clean up the audit_watch split No real changes, just cleanup to the audit_watch split patch which we done with minimal code changes for easy review. Now fix interfaces to make things work better. Signed-off-by: Eric Paris --- kernel/audit.c | 1 - kernel/audit.h | 13 ++++------ kernel/audit_watch.c | 67 ++++++++++++++++++++++++++++++---------------------- kernel/auditfilter.c | 41 ++++++++++++-------------------- kernel/auditsc.c | 5 ++-- 5 files changed, 60 insertions(+), 67 deletions(-) diff --git a/kernel/audit.c b/kernel/audit.c index c71bd26..05a32f0 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -56,7 +56,6 @@ #include #include #include -#include #include #include diff --git a/kernel/audit.h b/kernel/audit.h index 208687b..82c8a09 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -104,20 +104,15 @@ 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_add_watch(struct audit_krule *krule); -extern void audit_remove_watch(struct audit_watch *watch); +extern int audit_add_watch(struct audit_krule *krule, struct list_head **list); 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 void audit_watch_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); +extern int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev_t dev); +extern struct audit_entry *audit_dupe_rule(struct audit_krule *old); #ifdef CONFIG_AUDIT_TREE extern struct audit_chunk *audit_tree_lookup(const struct inode *); diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index 8df4369..c2ca716 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -51,12 +51,12 @@ struct audit_watch { 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 list_head rules; /* anchor for krule->rlist */ }; struct audit_parent { - struct list_head ilist; /* entry in inotify registration list */ - struct list_head watches; /* associated watches */ + struct list_head ilist; /* tmp list used to free parents */ + struct list_head watches; /* anchor for audit_watch->wlist */ struct inotify_watch wdata; /* inotify watch data */ unsigned flags; /* status flags */ }; @@ -78,13 +78,18 @@ struct inotify_handle *audit_ih; /* Inotify events we care about. */ #define AUDIT_IN_WATCH IN_MOVE|IN_CREATE|IN_DELETE|IN_DELETE_SELF|IN_MOVE_SELF -static void audit_free_parent(struct inotify_watch *i_watch) +static void audit_free_parent(struct audit_parent *parent) +{ + WARN_ON(!list_empty(&parent->watches)); + kfree(parent); +} + +static void audit_destroy_watch(struct inotify_watch *i_watch) { struct audit_parent *parent; parent = container_of(i_watch, struct audit_parent, wdata); - WARN_ON(!list_empty(&parent->watches)); - kfree(parent); + audit_free_parent(parent); } void audit_get_watch(struct audit_watch *watch) @@ -115,19 +120,11 @@ char *audit_watch_path(struct audit_watch *watch) return watch->path; } -struct list_head *audit_watch_rules(struct audit_watch *watch) +int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev_t dev) { - return &watch->rules; -} - -unsigned long audit_watch_inode(struct audit_watch *watch) -{ - return watch->ino; -} - -dev_t audit_watch_dev(struct audit_watch *watch) -{ - return watch->dev; + return (watch->ino != (unsigned long)-1) && + (watch->ino == ino) && + (watch->dev == dev); } /* Initialize a parent watch entry. */ @@ -149,7 +146,7 @@ static struct audit_parent *audit_init_parent(struct nameidata *ndp) wd = inotify_add_watch(audit_ih, &parent->wdata, ndp->path.dentry->d_inode, AUDIT_IN_WATCH); if (wd < 0) { - audit_free_parent(&parent->wdata); + audit_free_parent(parent); return ERR_PTR(wd); } @@ -251,15 +248,19 @@ static void audit_update_watch(struct audit_parent *parent, struct audit_entry *oentry, *nentry; mutex_lock(&audit_filter_mutex); + /* Run all of the watches on this parent looking for the one that + * matches the given dname */ list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) { if (audit_compare_dname_path(dname, owatch->path, NULL)) continue; /* If the update involves invalidating rules, do the inode-based * filtering now, so we don't omit records. */ - if (invalidating && current->audit_context) + if (invalidating && !audit_dummy_context()) audit_filter_inodes(current, current->audit_context); + /* updating ino will likely change which audit_hash_list we + * are on so we need a new watch for the new list */ nwatch = audit_dupe_watch(owatch); if (IS_ERR(nwatch)) { mutex_unlock(&audit_filter_mutex); @@ -275,12 +276,21 @@ static void audit_update_watch(struct audit_parent *parent, list_del(&oentry->rule.rlist); list_del_rcu(&oentry->list); - nentry = audit_dupe_rule(&oentry->rule, nwatch); + nentry = audit_dupe_rule(&oentry->rule); if (IS_ERR(nentry)) { list_del(&oentry->rule.list); audit_panic("error updating watch, removing"); } else { int h = audit_hash_ino((u32)ino); + + /* + * nentry->rule.watch == oentry->rule.watch so + * we must drop that reference and set it to our + * new watch. + */ + audit_put_watch(nentry->rule.watch); + audit_get_watch(nwatch); + nentry->rule.watch = nwatch; list_add(&nentry->rule.rlist, &nwatch->rules); list_add_rcu(&nentry->list, &audit_inode_hash[h]); list_replace(&oentry->rule.list, @@ -329,14 +339,14 @@ static void audit_remove_parent_watches(struct audit_parent *parent) /* Unregister inotify watches for parents on in_list. * Generates an IN_IGNORED event. */ -void audit_inotify_unregister(struct list_head *in_list) +void audit_watch_inotify_unregister(struct list_head *in_list) { struct audit_parent *p, *n; list_for_each_entry_safe(p, n, in_list, ilist) { list_del(&p->ilist); inotify_rm_watch(audit_ih, &p->wdata); - /* the unpin matching the pin in audit_do_del_rule() */ + /* the unpin matching the pin in audit_remove_watch_rule() */ unpin_inotify_watch(&p->wdata); } } @@ -423,13 +433,13 @@ 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) +int audit_add_watch(struct audit_krule *krule, struct list_head **list) { struct audit_watch *watch = krule->watch; struct inotify_watch *i_watch; struct audit_parent *parent; struct nameidata *ndp = NULL, *ndw = NULL; - int ret = 0; + int h, ret = 0; mutex_unlock(&audit_filter_mutex); @@ -475,6 +485,8 @@ int audit_add_watch(struct audit_krule *krule) /* match get in audit_init_parent or inotify_find_watch */ put_inotify_watch(&parent->wdata); + h = audit_hash_ino((u32)watch->ino); + *list = &audit_inode_hash[h]; error: audit_put_nd(ndp, ndw); /* NULL args OK */ return ret; @@ -514,8 +526,7 @@ static void audit_handle_ievent(struct inotify_watch *i_watch, u32 wd, u32 mask, parent = container_of(i_watch, struct audit_parent, wdata); if (mask & (IN_CREATE|IN_MOVED_TO) && inode) - audit_update_watch(parent, dname, inode->i_sb->s_dev, - inode->i_ino, 0); + audit_update_watch(parent, dname, inode->i_sb->s_dev, inode->i_ino, 0); else if (mask & (IN_DELETE|IN_MOVED_FROM)) audit_update_watch(parent, dname, (dev_t)-1, (unsigned long)-1, 1); /* inotify automatically removes the watch and sends IN_IGNORED */ @@ -531,7 +542,7 @@ static void audit_handle_ievent(struct inotify_watch *i_watch, u32 wd, u32 mask, static const struct inotify_operations audit_inotify_ops = { .handle_event = audit_handle_ievent, - .destroy_watch = audit_free_parent, + .destroy_watch = audit_destroy_watch, }; static int __init audit_watch_init(void) diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index ce08041..ac87577 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -71,6 +71,7 @@ static inline void audit_free_rule(struct audit_entry *e) { int i; struct audit_krule *erule = &e->rule; + /* some rules don't have associated watches */ if (erule->watch) audit_put_watch(erule->watch); @@ -746,8 +747,7 @@ static inline int audit_dupe_lsm_field(struct audit_field *df, * rule with the new rule in the filterlist, then free the old rule. * The rlist element is undefined; list manipulations are handled apart from * the initial copy. */ -struct audit_entry *audit_dupe_rule(struct audit_krule *old, - struct audit_watch *watch) +struct audit_entry *audit_dupe_rule(struct audit_krule *old) { u32 fcount = old->field_count; struct audit_entry *entry; @@ -769,8 +769,8 @@ struct audit_entry *audit_dupe_rule(struct audit_krule *old, new->prio = old->prio; new->buflen = old->buflen; new->inode_f = old->inode_f; - new->watch = NULL; new->field_count = old->field_count; + /* * note that we are OK with not refcounting here; audit_match_tree() * never dereferences tree and we can't get false positives there @@ -811,9 +811,9 @@ struct audit_entry *audit_dupe_rule(struct audit_krule *old, } } - if (watch) { - audit_get_watch(watch); - new->watch = watch; + if (old->watch) { + audit_get_watch(old->watch); + new->watch = old->watch; } return entry; @@ -866,7 +866,7 @@ static inline int audit_add_rule(struct audit_entry *entry) struct audit_watch *watch = entry->rule.watch; struct audit_tree *tree = entry->rule.tree; struct list_head *list; - int h, err; + int err; #ifdef CONFIG_AUDITSYSCALL int dont_count = 0; @@ -889,15 +889,11 @@ static inline int audit_add_rule(struct audit_entry *entry) if (watch) { /* audit_filter_mutex is dropped and re-taken during this call */ - err = audit_add_watch(&entry->rule); + err = audit_add_watch(&entry->rule, &list); if (err) { mutex_unlock(&audit_filter_mutex); goto error; } - /* entry->rule.watch may have changed during audit_add_watch() */ - watch = entry->rule.watch; - h = audit_hash_ino((u32)audit_watch_inode(watch)); - list = &audit_inode_hash[h]; } if (tree) { err = audit_add_tree_rule(&entry->rule); @@ -949,7 +945,7 @@ static inline int audit_del_rule(struct audit_entry *entry) struct audit_watch *watch = entry->rule.watch; struct audit_tree *tree = entry->rule.tree; struct list_head *list; - LIST_HEAD(inotify_list); + LIST_HEAD(inotify_unregister_list); int ret = 0; #ifdef CONFIG_AUDITSYSCALL int dont_count = 0; @@ -969,7 +965,7 @@ static inline int audit_del_rule(struct audit_entry *entry) } if (e->rule.watch) - audit_remove_watch_rule(&e->rule, &inotify_list); + audit_remove_watch_rule(&e->rule, &inotify_unregister_list); if (e->rule.tree) audit_remove_tree_rule(&e->rule); @@ -987,8 +983,8 @@ static inline int audit_del_rule(struct audit_entry *entry) #endif mutex_unlock(&audit_filter_mutex); - if (!list_empty(&inotify_list)) - audit_inotify_unregister(&inotify_list); + if (!list_empty(&inotify_unregister_list)) + audit_watch_inotify_unregister(&inotify_unregister_list); out: if (watch) @@ -1323,30 +1319,23 @@ static int update_lsm_rule(struct audit_krule *r) { struct audit_entry *entry = container_of(r, struct audit_entry, rule); struct audit_entry *nentry; - struct audit_watch *watch; - struct audit_tree *tree; int err = 0; if (!security_audit_rule_known(r)) return 0; - watch = r->watch; - tree = r->tree; - nentry = audit_dupe_rule(r, watch); + nentry = audit_dupe_rule(r); if (IS_ERR(nentry)) { /* save the first error encountered for the * return value */ err = PTR_ERR(nentry); audit_panic("error updating LSM filters"); - if (watch) + if (r->watch) list_del(&r->rlist); list_del_rcu(&entry->list); list_del(&r->list); } else { - if (watch) { - list_add(&nentry->rule.rlist, audit_watch_rules(watch)); - list_del(&r->rlist); - } else if (tree) + if (r->watch || r->tree) list_replace_init(&r->rlist, &nentry->rule.rlist); list_replace_rcu(&entry->list, &nentry->list); list_replace(&r->list, &nentry->rule.list); diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 3828ad5..240063c 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -549,9 +549,8 @@ static int audit_filter_rules(struct task_struct *tsk, } break; case AUDIT_WATCH: - if (name && audit_watch_inode(rule->watch) != (unsigned long)-1) - result = (name->dev == audit_watch_dev(rule->watch) && - name->ino == audit_watch_inode(rule->watch)); + if (name) + result = audit_watch_compare(rule->watch, name->ino, name->dev); break; case AUDIT_DIR: if (ctx) -- cgit v1.1