From: Mike Snitzer <snitzer@redhat.com>
Date: Fri, 28 Mar 2014 06:15:02 +0000 (-0400)
Subject: dm thin: fix dangling bio in process_deferred_bios error path
X-Git-Tag: v3.4.90~1
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=53b67ae8d3d01efbdfd7ae431d8d46cba70084b9;p=thirdparty%2Fkernel%2Fstable.git

dm thin: fix dangling bio in process_deferred_bios error path

commit fe76cd88e654124d1431bb662a0fc6e99ca811a5 upstream.

If unable to ensure_next_mapping() we must add the current bio, which
was removed from the @bios list via bio_list_pop, back to the
deferred_bios list before all the remaining @bios.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index c540dfff1f811..b253744fc3c84 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -1446,9 +1446,9 @@ static void process_deferred_bios(struct pool *pool)
 		 */
 		if (ensure_next_mapping(pool)) {
 			spin_lock_irqsave(&pool->lock, flags);
+			bio_list_add(&pool->deferred_bios, bio);
 			bio_list_merge(&pool->deferred_bios, &bios);
 			spin_unlock_irqrestore(&pool->lock, flags);
-
 			break;
 		}