From: Jan Kara <jack@suse.cz>
Date: Wed, 6 Sep 2017 06:25:51 +0000 (+0800)
Subject: bcache: Fix leak of bdev reference
X-Git-Tag: v4.14~380^2~13
X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=4b758df21ee7081ab41448d21d60367efaa625b3;p=mirror_ubuntu-bionic-kernel.git

bcache: Fix leak of bdev reference

If blkdev_get_by_path() in register_bcache() fails, we try to lookup the
block device using lookup_bdev() to detect which situation we are in to
properly report error. However we never drop the reference returned to
us from lookup_bdev(). Fix that.

Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Coly Li <colyli@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 974d832e54a6..c3fedd265d18 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1964,6 +1964,8 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
 			else
 				err = "device busy";
 			mutex_unlock(&bch_register_lock);
+			if (!IS_ERR(bdev))
+				bdput(bdev);
 			if (attr == &ksysfs_register_quiet)
 				goto out;
 		}