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-rw-r--r--kernel/audit_watch.c274
1 files changed, 149 insertions, 125 deletions
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index 8df4369..6bf2306 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -24,18 +24,18 @@
#include <linux/kthread.h>
#include <linux/mutex.h>
#include <linux/fs.h>
+#include <linux/fsnotify_backend.h>
#include <linux/namei.h>
#include <linux/netlink.h>
#include <linux/sched.h>
#include <linux/slab.h>
-#include <linux/inotify.h>
#include <linux/security.h>
#include "audit.h"
/*
* Reference counting:
*
- * audit_parent: lifetime is from audit_init_parent() to receipt of an IN_IGNORED
+ * audit_parent: lifetime is from audit_init_parent() to receipt of an FS_IGNORED
* event. Each audit_watch holds a reference to its associated parent.
*
* audit_watch: if added to lists, lifetime is from audit_init_watch() to
@@ -51,40 +51,61 @@ 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 inotify_watch wdata; /* inotify watch data */
- unsigned flags; /* status flags */
+ struct list_head watches; /* anchor for audit_watch->wlist */
+ struct fsnotify_mark mark; /* fsnotify mark on the inode */
};
-/* Inotify handle. */
-struct inotify_handle *audit_ih;
+/* fsnotify handle. */
+struct fsnotify_group *audit_watch_group;
-/*
- * audit_parent status flags:
- *
- * AUDIT_PARENT_INVALID - set anytime rules/watches are auto-removed due to
- * a filesystem event to ensure we're adding audit watches to a valid parent.
- * Technically not needed for IN_DELETE_SELF or IN_UNMOUNT events, as we cannot
- * receive them while we have nameidata, but must be used for IN_MOVE_SELF which
- * we can receive while holding nameidata.
- */
-#define AUDIT_PARENT_INVALID 0x001
+/* fsnotify events we care about. */
+#define AUDIT_FS_WATCH (FS_MOVE | FS_CREATE | FS_DELETE | FS_DELETE_SELF |\
+ FS_MOVE_SELF | FS_EVENT_ON_CHILD)
-/* 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 audit_parent *parent)
+{
+ WARN_ON(!list_empty(&parent->watches));
+ kfree(parent);
+}
-static void audit_free_parent(struct inotify_watch *i_watch)
+static void audit_watch_free_mark(struct fsnotify_mark *entry)
{
struct audit_parent *parent;
- parent = container_of(i_watch, struct audit_parent, wdata);
- WARN_ON(!list_empty(&parent->watches));
- kfree(parent);
+ parent = container_of(entry, struct audit_parent, mark);
+ audit_free_parent(parent);
+}
+
+static void audit_get_parent(struct audit_parent *parent)
+{
+ if (likely(parent))
+ fsnotify_get_mark(&parent->mark);
+}
+
+static void audit_put_parent(struct audit_parent *parent)
+{
+ if (likely(parent))
+ fsnotify_put_mark(&parent->mark);
+}
+
+/*
+ * Find and return the audit_parent on the given inode. If found a reference
+ * is taken on this parent.
+ */
+static inline struct audit_parent *audit_find_parent(struct inode *inode)
+{
+ struct audit_parent *parent = NULL;
+ struct fsnotify_mark *entry;
+
+ entry = fsnotify_find_inode_mark(audit_watch_group, inode);
+ if (entry)
+ parent = container_of(entry, struct audit_parent, mark);
+
+ return parent;
}
void audit_get_watch(struct audit_watch *watch)
@@ -105,7 +126,7 @@ void audit_put_watch(struct audit_watch *watch)
void audit_remove_watch(struct audit_watch *watch)
{
list_del(&watch->wlist);
- put_inotify_watch(&watch->parent->wdata);
+ audit_put_parent(watch->parent);
watch->parent = NULL;
audit_put_watch(watch); /* match initial get */
}
@@ -115,42 +136,32 @@ char *audit_watch_path(struct audit_watch *watch)
return watch->path;
}
-struct list_head *audit_watch_rules(struct audit_watch *watch)
-{
- return &watch->rules;
-}
-
-unsigned long audit_watch_inode(struct audit_watch *watch)
+int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev_t dev)
{
- 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. */
static struct audit_parent *audit_init_parent(struct nameidata *ndp)
{
+ struct inode *inode = ndp->path.dentry->d_inode;
struct audit_parent *parent;
- s32 wd;
+ int ret;
parent = kzalloc(sizeof(*parent), GFP_KERNEL);
if (unlikely(!parent))
return ERR_PTR(-ENOMEM);
INIT_LIST_HEAD(&parent->watches);
- parent->flags = 0;
-
- inotify_init_watch(&parent->wdata);
- /* grab a ref so inotify watch hangs around until we take audit_filter_mutex */
- get_inotify_watch(&parent->wdata);
- wd = inotify_add_watch(audit_ih, &parent->wdata,
- ndp->path.dentry->d_inode, AUDIT_IN_WATCH);
- if (wd < 0) {
- audit_free_parent(&parent->wdata);
- return ERR_PTR(wd);
+
+ fsnotify_init_mark(&parent->mark, audit_watch_free_mark);
+ parent->mark.mask = AUDIT_FS_WATCH;
+ ret = fsnotify_add_mark(&parent->mark, audit_watch_group, inode, NULL, 0);
+ if (ret < 0) {
+ audit_free_parent(parent);
+ return ERR_PTR(ret);
}
return parent;
@@ -179,7 +190,7 @@ int audit_to_watch(struct audit_krule *krule, char *path, int len, u32 op)
{
struct audit_watch *watch;
- if (!audit_ih)
+ if (!audit_watch_group)
return -EOPNOTSUPP;
if (path[0] != '/' || path[len-1] == '/' ||
@@ -217,7 +228,7 @@ static struct audit_watch *audit_dupe_watch(struct audit_watch *old)
new->dev = old->dev;
new->ino = old->ino;
- get_inotify_watch(&old->parent->wdata);
+ audit_get_parent(old->parent);
new->parent = old->parent;
out:
@@ -251,15 +262,19 @@ 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 +290,21 @@ 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,
@@ -312,7 +336,6 @@ static void audit_remove_parent_watches(struct audit_parent *parent)
struct audit_entry *e;
mutex_lock(&audit_filter_mutex);
- parent->flags |= AUDIT_PARENT_INVALID;
list_for_each_entry_safe(w, nextw, &parent->watches, wlist) {
list_for_each_entry_safe(r, nextr, &w->rules, rlist) {
e = container_of(r, struct audit_entry, rule);
@@ -325,20 +348,8 @@ static void audit_remove_parent_watches(struct audit_parent *parent)
audit_remove_watch(w);
}
mutex_unlock(&audit_filter_mutex);
-}
-
-/* Unregister inotify watches for parents on in_list.
- * Generates an IN_IGNORED event. */
-void audit_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() */
- unpin_inotify_watch(&p->wdata);
- }
+ fsnotify_destroy_mark(&parent->mark);
}
/* Get path information necessary for adding watches. */
@@ -389,7 +400,7 @@ static void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw)
}
}
-/* Associate the given rule with an existing parent inotify_watch.
+/* Associate the given rule with an existing parent.
* Caller must hold audit_filter_mutex. */
static void audit_add_to_parent(struct audit_krule *krule,
struct audit_parent *parent)
@@ -397,6 +408,8 @@ static void audit_add_to_parent(struct audit_krule *krule,
struct audit_watch *w, *watch = krule->watch;
int watch_found = 0;
+ BUG_ON(!mutex_is_locked(&audit_filter_mutex));
+
list_for_each_entry(w, &parent->watches, wlist) {
if (strcmp(watch->path, w->path))
continue;
@@ -413,7 +426,7 @@ static void audit_add_to_parent(struct audit_krule *krule,
}
if (!watch_found) {
- get_inotify_watch(&parent->wdata);
+ audit_get_parent(parent);
watch->parent = parent;
list_add(&watch->wlist, &parent->watches);
@@ -423,13 +436,12 @@ 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);
@@ -441,47 +453,38 @@ int audit_add_watch(struct audit_krule *krule)
goto error;
}
+ mutex_lock(&audit_filter_mutex);
+
/* update watch filter fields */
if (ndw) {
watch->dev = ndw->path.dentry->d_inode->i_sb->s_dev;
watch->ino = ndw->path.dentry->d_inode->i_ino;
}
- /* The audit_filter_mutex must not be held during inotify calls because
- * we hold it during inotify event callback processing. If an existing
- * inotify watch is found, inotify_find_watch() grabs a reference before
- * returning.
- */
- if (inotify_find_watch(audit_ih, ndp->path.dentry->d_inode,
- &i_watch) < 0) {
+ /* either find an old parent or attach a new one */
+ parent = audit_find_parent(ndp->path.dentry->d_inode);
+ if (!parent) {
parent = audit_init_parent(ndp);
if (IS_ERR(parent)) {
- /* caller expects mutex locked */
- mutex_lock(&audit_filter_mutex);
ret = PTR_ERR(parent);
goto error;
}
- } else
- parent = container_of(i_watch, struct audit_parent, wdata);
-
- mutex_lock(&audit_filter_mutex);
+ }
- /* parent was moved before we took audit_filter_mutex */
- if (parent->flags & AUDIT_PARENT_INVALID)
- ret = -ENOENT;
- else
- audit_add_to_parent(krule, parent);
+ audit_add_to_parent(krule, parent);
- /* match get in audit_init_parent or inotify_find_watch */
- put_inotify_watch(&parent->wdata);
+ /* match get in audit_find_parent or audit_init_parent */
+ audit_put_parent(parent);
+ h = audit_hash_ino((u32)watch->ino);
+ *list = &audit_inode_hash[h];
error:
audit_put_nd(ndp, ndw); /* NULL args OK */
return ret;
}
-void audit_remove_watch_rule(struct audit_krule *krule, struct list_head *list)
+void audit_remove_watch_rule(struct audit_krule *krule)
{
struct audit_watch *watch = krule->watch;
struct audit_parent *parent = watch->parent;
@@ -492,53 +495,74 @@ void audit_remove_watch_rule(struct audit_krule *krule, struct list_head *list)
audit_remove_watch(watch);
if (list_empty(&parent->watches)) {
- /* Put parent on the inotify un-registration
- * list. Grab a reference before releasing
- * audit_filter_mutex, to be released in
- * audit_inotify_unregister().
- * If filesystem is going away, just leave
- * the sucker alone, eviction will take
- * care of it. */
- if (pin_inotify_watch(&parent->wdata))
- list_add(&parent->ilist, list);
+ audit_get_parent(parent);
+ fsnotify_destroy_mark(&parent->mark);
+ audit_put_parent(parent);
}
}
}
-/* Update watch data in audit rules based on inotify events. */
-static void audit_handle_ievent(struct inotify_watch *i_watch, u32 wd, u32 mask,
- u32 cookie, const char *dname, struct inode *inode)
+static bool audit_watch_should_send_event(struct fsnotify_group *group, struct inode *inode,
+ struct fsnotify_mark *inode_mark,
+ struct fsnotify_mark *vfsmount_mark,
+ __u32 mask, void *data, int data_type)
+{
+ return true;
+}
+
+/* Update watch data in audit rules based on fsnotify events. */
+static int audit_watch_handle_event(struct fsnotify_group *group,
+ struct fsnotify_mark *inode_mark,
+ struct fsnotify_mark *vfsmount_mark,
+ struct fsnotify_event *event)
{
+ struct inode *inode;
+ __u32 mask = event->mask;
+ const char *dname = event->file_name;
struct audit_parent *parent;
- parent = container_of(i_watch, struct audit_parent, wdata);
+ parent = container_of(inode_mark, struct audit_parent, mark);
- if (mask & (IN_CREATE|IN_MOVED_TO) && inode)
- audit_update_watch(parent, dname, inode->i_sb->s_dev,
- inode->i_ino, 0);
- else if (mask & (IN_DELETE|IN_MOVED_FROM))
+ BUG_ON(group != audit_watch_group);
+
+ switch (event->data_type) {
+ case (FSNOTIFY_EVENT_FILE):
+ inode = event->file->f_path.dentry->d_inode;
+ break;
+ case (FSNOTIFY_EVENT_INODE):
+ inode = event->inode;
+ break;
+ default:
+ BUG();
+ inode = NULL;
+ break;
+ };
+
+ if (mask & (FS_CREATE|FS_MOVED_TO) && inode)
+ audit_update_watch(parent, dname, inode->i_sb->s_dev, inode->i_ino, 0);
+ else if (mask & (FS_DELETE|FS_MOVED_FROM))
audit_update_watch(parent, dname, (dev_t)-1, (unsigned long)-1, 1);
- /* inotify automatically removes the watch and sends IN_IGNORED */
- else if (mask & (IN_DELETE_SELF|IN_UNMOUNT))
- audit_remove_parent_watches(parent);
- /* inotify does not remove the watch, so remove it manually */
- else if(mask & IN_MOVE_SELF) {
+ else if (mask & (FS_DELETE_SELF|FS_UNMOUNT|FS_MOVE_SELF))
audit_remove_parent_watches(parent);
- inotify_remove_watch_locked(audit_ih, i_watch);
- } else if (mask & IN_IGNORED)
- put_inotify_watch(i_watch);
+
+ return 0;
}
-static const struct inotify_operations audit_inotify_ops = {
- .handle_event = audit_handle_ievent,
- .destroy_watch = audit_free_parent,
+static const struct fsnotify_ops audit_watch_fsnotify_ops = {
+ .should_send_event = audit_watch_should_send_event,
+ .handle_event = audit_watch_handle_event,
+ .free_group_priv = NULL,
+ .freeing_mark = NULL,
+ .free_event_priv = NULL,
};
static int __init audit_watch_init(void)
{
- audit_ih = inotify_init(&audit_inotify_ops);
- if (IS_ERR(audit_ih))
- audit_panic("cannot initialize inotify handle");
+ audit_watch_group = fsnotify_alloc_group(&audit_watch_fsnotify_ops);
+ if (IS_ERR(audit_watch_group)) {
+ audit_watch_group = NULL;
+ audit_panic("cannot create audit fsnotify group");
+ }
return 0;
}
-subsys_initcall(audit_watch_init);
+device_initcall(audit_watch_init);
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