Commit 81e759fb authored by Josh Durgin's avatar Josh Durgin Committed by Sage Weil
Browse files

rbd: return an error when an invalid header is read 



This protects against opening future rbd images that have incompatible format changes.

Signed-off-by: default avatarJosh Durgin <josh.durgin@dreamhost.com>
parent 2151937d

drivers/block/rbd.c

+10 −1
Original line number Diff line number Diff line
@@ -461,6 +461,10 @@ static int rbd_header_from_disk(struct rbd_image_header *header, 
	u32 snap_count = le32_to_cpu(ondisk->snap_count);

	int ret = -ENOMEM;



	if (memcmp(ondisk, RBD_HEADER_TEXT, sizeof(RBD_HEADER_TEXT))) {

		return -ENXIO;

	}



	init_rwsem(&header->snap_rwsem);

	header->snap_names_len = le64_to_cpu(ondisk->snap_names_len);

	header->snapc = kmalloc(sizeof(struct ceph_snap_context) +
@@ -1610,8 +1614,13 @@ static int rbd_read_header(struct rbd_device *rbd_dev, 
			goto out_dh;



		rc = rbd_header_from_disk(header, dh, snap_count, GFP_KERNEL);

		if (rc < 0)

		if (rc < 0) {

			if (rc == -ENXIO) {

				pr_warning("unrecognized header format"

					   " for image %s", rbd_dev->obj);

			}

			goto out_dh;

		}



		if (snap_count != header->total_snaps) {

			snap_count = header->total_snaps;