Commit fed13a54 authored by Mikulas Patocka's avatar Mikulas Patocka
Browse files

dm: fix a crash if blk_alloc_disk fails 



If blk_alloc_disk fails, the variable md->disk is set to an error value.
cleanup_mapped_device will see that md->disk is non-NULL and it will
attempt to access it, causing a crash on this statement
"md->disk->private_data = NULL;".

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Reported-by: default avatarChenyuan Yang <chenyuan0y@gmail.com>
Closes: https://marc.info/?l=dm-devel&m=172824125004329&w=2


Cc: stable@vger.kernel.org
Reviewed-by: default avatarNitesh Shetty <nj.shetty@samsung.com>
parent 8e929cb5

drivers/md/dm.c

+3 −1
Original line number Diff line number Diff line
@@ -2290,8 +2290,10 @@ static struct mapped_device *alloc_dev(int minor) 
	 * override accordingly.

	 */

	md->disk = blk_alloc_disk(NULL, md->numa_node_id);

	if (IS_ERR(md->disk))

	if (IS_ERR(md->disk)) {

		md->disk = NULL;

		goto bad;

	}

	md->queue = md->disk->queue;



	init_waitqueue_head(&md->wait);