From: Mike Snitzer <snitzer@redhat.com>
Date: Thu, 22 Oct 2015 14:56:40 +0000 (-0400)
Subject: dm btree: fix leak of bufio-backed block in btree_split_beneath error path
X-Git-Tag: v4.2.6~42
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2b1033516c578caaf96354d338ea7e6ce3143afd;p=thirdparty%2Fkernel%2Fstable.git

dm btree: fix leak of bufio-backed block in btree_split_beneath error path

commit 4dcb8b57df3593dcb20481d9d6cf79d1dc1534be upstream.

btree_split_beneath()'s error path had an outstanding FIXME that speaks
directly to the potential for _not_ cleaning up a previously allocated
bufio-backed block.

Fix this by releasing the previously allocated bufio block using
unlock_block().

Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <thornber@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/md/persistent-data/dm-btree.c b/drivers/md/persistent-data/dm-btree.c
index c7726cebc4950..d6e47033b5e0d 100644
--- a/drivers/md/persistent-data/dm-btree.c
+++ b/drivers/md/persistent-data/dm-btree.c
@@ -523,7 +523,7 @@ static int btree_split_beneath(struct shadow_spine *s, uint64_t key)
 
 	r = new_block(s->info, &right);
 	if (r < 0) {
-		/* FIXME: put left */
+		unlock_block(s->info, left);
 		return r;
 	}