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-Url: http://git.mmlx.us/?a=commitdiff_plain;h=e2e8845036f5cd4391fc753367604562c65d8008;p=linux-edison.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 901aac27e52..7d0ac0a6e72 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -1322,9 +1322,9 @@ 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;
 		}