bcache: Fix leak of bdev reference

[ Upstream commit 4b758df21ee7081ab41448d21d60367efaa625b3 ]

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>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 2b4fae01381f3bace759797e306cab4421953dfe..38522cc6b26d133735471274c56df3c3ac08f75d 100644 (file)
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1997,6 +1997,8 @@ 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;
                }