From: Christoph Hellwig <hch@xxxxxx> [ Upstream commit d90db3b1c8676bc88b4309c5a571333de2263b8e ] Zero out the pointer to ->slave_dir so that the holder code doesn't incorrectly treat the object as alive when add_disk failed or after del_gendisk was called. Fixes: 89f871af1b26 ("dm: delay registering the gendisk") Reported-by: Yu Kuai <yukuai3@xxxxxxxxxx> Signed-off-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx> Reviewed-by: Mike Snitzer <snitzer@xxxxxxxxxx> Link: https://lore.kernel.org/r/20221115141054.1051801-2-yukuai1@xxxxxxxxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- block/genhd.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/block/genhd.c b/block/genhd.c index 0f9769db2de8..647f7d8d8831 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -530,6 +530,7 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk, rq_qos_exit(disk->queue); out_put_slave_dir: kobject_put(disk->slave_dir); + disk->slave_dir = NULL; out_put_holder_dir: kobject_put(disk->part0->bd_holder_dir); out_del_integrity: @@ -629,6 +630,7 @@ void del_gendisk(struct gendisk *disk) kobject_put(disk->part0->bd_holder_dir); kobject_put(disk->slave_dir); + disk->slave_dir = NULL; part_stat_set_all(disk->part0, 0); disk->part0->bd_stamp = 0; -- 2.35.1