[PATCH 25/26] audit: fix mark refcounting

Eric Paris
2011-11-17T22:05:05Z

From: Miklos Szeredi <mszeredi@suse.cz>

Removing the parent of a watched file results in "kernel BUG at
fs/notify/mark.c:139".

To reproduce

add "-w /tmp/audit/dir/watched_file" to audit.rules
rm -rf /tmp/audit/dir

This is caused by fsnotify_destroy_mark() being called without an
extra reference taken by the caller.

Reported by Francesco Cosoleto here:

https://bugzilla.novell.com/show_bug.cgi?id=689860

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Al Viro <viro@zeniv.linux.org.uk>
CC: Eric Paris <eparis@redhat.com>
CC: stable@vger.kernel.org
Signed-off-by: Eric Paris <eparis@redhat.com>
---

kernel/audit_watch.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index e683869..4270d84 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -349,7 +349,9 @@ static void audit_remove_parent_watches(struct audit_parent *parent)
}
mutex_unlock(&audit_filter_mutex);

+ audit_get_parent(parent);
fsnotify_destroy_mark(&parent->mark);
+ audit_put_parent(parent);
}

/* Get path information necessary for adding watches. */