From 0b045bd1c1c2819b33f4522e3efa4666d1ecf1a4 Mon Sep 17 00:00:00 2001
From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Mon, 11 Sep 2017 21:43:23 +0200
Subject: [PATCH] mm/backing-dev.c: fix an error handling path in
 'cgwb_create()'

If the 'kmalloc' fails, we must go through the existing error handling
path.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Fixes: 52ebea749aae ("writeback: make backing_dev_info host cgroup-specific bdi_writebacks")
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 mm/backing-dev.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index f028a9a472fd9b..e19606bb41a0b5 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -569,8 +569,10 @@ static int cgwb_create(struct backing_dev_info *bdi,
 
 	/* need to create a new one */
 	wb = kmalloc(sizeof(*wb), gfp);
-	if (!wb)
-		return -ENOMEM;
+	if (!wb) {
+		ret = -ENOMEM;
+		goto out_put;
+	}
 
 	ret = wb_init(wb, bdi, blkcg_css->id, gfp);
 	if (ret)