From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Date: Sun, 24 Aug 2014 08:48:17 -0700 Subject: [Cluster-devel] [PATCH 01/10] locks: close potential race in lease_get_mtime In-Reply-To: <1408804878-1331-2-git-send-email-jlayton@primarydata.com> References: <1408804878-1331-1-git-send-email-jlayton@primarydata.com> <1408804878-1331-2-git-send-email-jlayton@primarydata.com> Message-ID: <20140824154817.GA15908@infradead.org> List-Id: To: cluster-devel.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Sat, Aug 23, 2014 at 10:41:09AM -0400, Jeff Layton wrote: > lease_get_mtime is called without the i_lock held, so there's no > guarantee about the stability of the list. Between the time when we > assign "flock" and then dereference it to check whether it's a lease > and for write, the lease could be freed. > > Ensure that that doesn't occur by taking the i_lock before trying > to check the lease. Looks good. Also looks way cleaner than before by being just a tad more verbose.. Reviewed-by: Christoph Hellwig