From: Hou Tao <houtao1@huawei.com>
Date: Fri, 3 Feb 2017 09:19:07 +0000 (+0800)
Subject: blkcg: fix double free of new_blkg in blkcg_init_queue
X-Git-Tag: v4.4.123~130
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=633a5a5235d697b145171ca1e702d3a4f6778131;p=thirdparty%2Fkernel%2Fstable.git

blkcg: fix double free of new_blkg in blkcg_init_queue

commit 9b54d816e00425c3a517514e0d677bb3cec49258 upstream.

If blkg_create fails, new_blkg passed as an argument will
be freed by blkg_create, so there is no need to free it again.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 8161090a19708..46ba2402c8f97 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1078,10 +1078,8 @@ int blkcg_init_queue(struct request_queue *q)
 	if (preloaded)
 		radix_tree_preload_end();
 
-	if (IS_ERR(blkg)) {
-		blkg_free(new_blkg);
+	if (IS_ERR(blkg))
 		return PTR_ERR(blkg);
-	}
 
 	q->root_blkg = blkg;
 	q->root_rl.blkg = blkg;