nvmet: fix NULL pointer dereference in nvmet_execute_identify_ns_zns()

When a host issues an Identify command with CNS 05h (I/O Command Set
specific Identify Namespace) and CSI 02h (ZNS) targeting a file-backed
namespace, nvmet_execute_identify_ns_zns() calls bdev_is_zoned() on
req->ns->bdev. A file-backed namespace has no block device, so
req->ns->bdev is NULL and bdev_is_zoned() dereferences it, oopsing.

The I/O command set is selected by the host-supplied CSI field and the
command is routed here whenever CONFIG_BLK_DEV_ZONED is enabled,
independent of the namespace backing type, so any file-backed namespace
is exposed.

Reject the command with Invalid Field when the namespace is not backed
by a block device.

Fixes: aaf2e048af27 ("nvmet: add ZBD over ZNS backend support")
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Guixin Liu <kanie@linux.alibaba.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

0 files changed, 0 insertions, 0 deletions