patches/dm-btree-fix-leak-of-bufio-backed-block-in-btree_split_sibling-error-path.patch

From 30ce6e1cc5a0f781d60227e9096c86e188d2c2bd Mon Sep 17 00:00:00 2001
From: Mike Snitzer <snitzer@redhat.com>
Date: Mon, 23 Nov 2015 16:24:45 -0500
Subject: dm btree: fix leak of bufio-backed block in btree_split_sibling error
 path

commit 30ce6e1cc5a0f781d60227e9096c86e188d2c2bd upstream.

The block allocated at the start of btree_split_sibling() is never
released if later insert_at() fails.

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>
Signed-off-by: Zefan Li <lizefan@huawei.com>
---
 drivers/md/persistent-data/dm-btree.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/md/persistent-data/dm-btree.c
+++ b/drivers/md/persistent-data/dm-btree.c
@@ -450,8 +450,10 @@ static int btree_split_sibling(struct sh
 
 	r = insert_at(sizeof(__le64), pn, parent_index + 1,
 		      le64_to_cpu(rn->keys[0]), &location);
-	if (r)
+	if (r) {
+		unlock_block(s->info, right);
 		return r;
+	}
 
 	if (key < le64_to_cpu(rn->keys[0])) {
 		unlock_block(s->info, right);