From: Yu Kuai <yukuai3@huawei.com>

Date: Tue, 7 Mar 2023 18:55:52 +0800

Subject: [PATCH] block: fix wrong mode for blkdev_put() from

 disk_scan_partitions()

References: bsc#1012628

Patch-mainline: 6.2.7

Git-commit: 428913bce1e67ccb4dae317fd0332545bf8c9233

[ Upstream commit 428913bce1e67ccb4dae317fd0332545bf8c9233 ]

If disk_scan_partitions() is called with 'FMODE_EXCL',

blkdev_get_by_dev() will be called without 'FMODE_EXCL', however, follow

blkdev_put() is still called with 'FMODE_EXCL', which will cause

'bd_holders' counter to leak.

Fix the problem by using the right mode for blkdev_put().

Reported-by: syzbot+2bcc0d79e548c4f62a59@syzkaller.appspotmail.com

Link: https://lore.kernel.org/lkml/f9649d501bc8c3444769418f6c26263555d9d3be.camel@linux.ibm.com/T/

Tested-by: Julian Ruess <julianr@linux.ibm.com>

Fixes: e5cfefa97bcc ("block: fix scan partition for exclusively open device again")

Signed-off-by: Yu Kuai <yukuai3@huawei.com>

Reviewed-by: Jan Kara <jack@suse.cz>

Signed-off-by: Jens Axboe <axboe@kernel.dk>

Signed-off-by: Sasha Levin <sashal@kernel.org>

Signed-off-by: Jiri Slaby <jslaby@suse.cz>

---

 block/genhd.c | 2 +-

 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/genhd.c b/block/genhd.c

index 6cdaeb71..9c4c9aa5 100644

--- a/block/genhd.c

+++ b/block/genhd.c

@@ -385,7 +385,7 @@ int disk_scan_partitions(struct gendisk *disk, fmode_t mode)

 	if (IS_ERR(bdev))

 		ret =  PTR_ERR(bdev);

 	else

-		blkdev_put(bdev, mode);

+		blkdev_put(bdev, mode & ~FMODE_EXCL);

 	if (!(mode & FMODE_EXCL))

 		bd_abort_claiming(disk->part0, disk_scan_partitions);

-- 

2.35.3