Patch "bcache: Fix leak of bdev reference" has been added to the 4.4-stable tree

Patch "bcache: Fix leak of bdev reference" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    bcache: Fix leak of bdev reference

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     bcache-fix-leak-of-bdev-reference.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 4b758df21ee7081ab41448d21d60367efaa625b3 Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@suse.cz>
Date: Wed, 6 Sep 2017 14:25:51 +0800
Subject: bcache: Fix leak of bdev reference

From: Jan Kara <jack@suse.cz>

commit 4b758df21ee7081ab41448d21d60367efaa625b3 upstream.

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>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/md/bcache/super.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1960,6 +1960,8 @@ static ssize_t register_bcache(struct ko
 			else
 				err = "device busy";
 			mutex_unlock(&bch_register_lock);
+			if (!IS_ERR(bdev))
+				bdput(bdev);
 			if (attr == &ksysfs_register_quiet)
 				goto out;
 		}


Patches currently in stable-queue which might be from jack@suse.cz are

queue-4.4/ext4-fix-quota-inconsistency-during-orphan-cleanup-for-read-only-mounts.patch
queue-4.4/bcache-fix-leak-of-bdev-reference.patch
queue-4.4/ext4-fix-incorrect-quotaoff-if-the-quota-feature-is-enabled.patch