inotify: fix coalesce duplicate events into a single event in special case

commit 3de0ef4f2067da58fa5126d821a56dcb98cdb565 upstream.

If we do rename a dir entry, like this:

  rename("/tmp/ino7UrgoJ.rename1", "/tmp/ino7UrgoJ.rename2")
  rename("/tmp/ino7UrgoJ.rename2", "/tmp/ino7UrgoJ")

The duplicate events should be coalesced into a single event. But those two
events do not be coalesced into a single event, due to some bad check in
event_compare(). It can not match the two NULL inodes as the same event.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/notify/notification.c b/fs/notify/notification.c
index 3816d5750dd55eb6f8b2c710b6a017a4694b450c..b8bf53b4c10897802c83db2c1ce1320aad16236e 100644 (file)
--- a/fs/notify/notification.c
+++ b/fs/notify/notification.c
@@ -143,7 +143,7 @@ static bool event_compare(struct fsnotify_event *old, struct fsnotify_event *new
                        /* remember, after old was put on the wait_q we aren't
                         * allowed to look at the inode any more, only thing
                         * left to check was if the file_name is the same */
-                       if (old->name_len &&
+                       if (!old->name_len ||
                            !strcmp(old->file_name, new->file_name))
                                return true;
                        break;