From 86af0f992e2a5cfabcd431ec107bea0400cddb04 Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Wed, 27 Feb 2019 14:58:58 +0100
Subject: Revert "loop: Fix double mutex_unlock(&loop_ctl_mutex) in
 loop_control_ioctl()"

This reverts commit 5d3cf50105d007adc54949e0caeca1e944549723 which is
commit 628bd85947091830a8c4872adfd5ed1d515a9cf2 upstream.

It does not work properly in the 4.9.y tree and causes more problems
than it fixes, so revert it.

Reported-by: Thomas Lindroth <thomas.lindroth@gmail.com>
Reported-by: Jan Kara <jack@suse.cz>
Cc: syzbot <syzbot+c0138741c2290fc5e63f@syzkaller.appspotmail.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/block/loop.c | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'drivers/block/loop.c')

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 344f34746c10..4af7b080c6c7 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1929,10 +1929,12 @@ static long loop_control_ioctl(struct file *file, unsigned int cmd,
 			break;
 		if (lo->lo_state != Lo_unbound) {
 			ret = -EBUSY;
+			mutex_unlock(&loop_ctl_mutex);
 			break;
 		}
 		if (atomic_read(&lo->lo_refcnt) > 0) {
 			ret = -EBUSY;
+			mutex_unlock(&loop_ctl_mutex);
 			break;
 		}
 		lo->lo_disk->private_data = NULL;
-- 
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