[PATCH 5.15 135/177] btrfs: fix missing blkdev_put() call in btrfs_scan_one_device()

From: Greg Kroah-Hartman
Date: Mon Dec 20 2021 - 10:20:46 EST


From: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx>

commit 4989d4a0aed3fb30f5b48787a689d7090de6f86d upstream.

The function btrfs_scan_one_device() calls blkdev_get_by_path() and
blkdev_put() to get and release its target block device. However, when
btrfs_sb_log_location_bdev() fails, blkdev_put() is not called and the
block device is left without clean up. This triggered failure of fstests
generic/085. Fix the failure path of btrfs_sb_log_location_bdev() to
call blkdev_put().

Fixes: 12659251ca5df ("btrfs: implement log-structured superblock for ZONED mode")
CC: stable@xxxxxxxxxxxxxxx # 5.15+
Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx>
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@xxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/btrfs/volumes.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1366,8 +1366,10 @@ struct btrfs_device *btrfs_scan_one_devi

bytenr_orig = btrfs_sb_offset(0);
ret = btrfs_sb_log_location_bdev(bdev, 0, READ, &bytenr);
- if (ret)
- return ERR_PTR(ret);
+ if (ret) {
+ device = ERR_PTR(ret);
+ goto error_bdev_put;
+ }

disk_super = btrfs_read_disk_super(bdev, bytenr, bytenr_orig);
if (IS_ERR(disk_super)) {