From: Mike Snitzer <snitzer@redhat.com>
Date: Mon, 23 Nov 2015 21:24:45 +0000 (-0500)
Subject: dm btree: fix leak of bufio-backed block in btree_split_sibling error path
X-Git-Tag: v3.4.113~64
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=86325076e9777158fa4bd3946c7907b78d69f1eb;p=thirdparty%2Fkernel%2Fstable.git

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>
---

diff --git a/drivers/md/persistent-data/dm-btree.c b/drivers/md/persistent-data/dm-btree.c
index be86d59eaa900..77c615eaab44b 100644
--- 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 shadow_spine *s, dm_block_t root,
 
 	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);