Re: [patch] updated inotify for 2.6.12-rc3.

[Robert Love <rml@novell.com>]

On Fri, 2005-04-22 at 22:13 +0100, Al Viro wrote:

> Or it would, if remove_watch() had been called only once.  In the scenario
> above that will not be true.

Thanks.

	Robert Love


Double check that we don't race.

Signed-off-by: Robert Love <rml@novell.com>

 fs/inotify.c |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

diff -urN linux-2.6.12-rc3-inotify/fs/inotify.c linux/fs/inotify.c
--- linux-2.6.12-rc3-inotify/fs/inotify.c	2005-04-22 19:20:14.000000000 -0400
+++ linux/fs/inotify.c	2005-04-22 19:25:44.000000000 -0400
@@ -861,12 +861,17 @@
 		return -EINVAL;
 	}
 	get_inotify_watch(watch);
+	inode = watch->inode;	
 	up(&dev->sem);
 
-	inode = watch->inode;
 	down(&inode->inotify_sem);
 	down(&dev->sem);
-	remove_watch(watch, dev);
+
+	/* make sure we did not race */
+	watch = idr_find(&dev->idr, wd);
+	if (likely(watch))
+		remove_watch(watch, dev);
+
 	up(&dev->sem);
 	up(&inode->inotify_sem);
 	put_inotify_watch(watch);