Commit a26116c1 authored by Rafael Mendonca's avatar Rafael Mendonca Committed by Michael S. Tsirkin
Browse files

virtio_blk: Fix signedness bug in virtblk_prep_rq() 



The virtblk_map_data() function returns negative error codes, however, the
'nents' field of vbr->sg_table is an unsigned int, which causes the error
handling not to work correctly.

Cc: stable@vger.kernel.org
Fixes: 0e9911fa ("virtio-blk: support mq_ops->queue_rqs()")
Signed-off-by: default avatarRafael Mendonca <rafaelmendsr@gmail.com>
Message-Id: <20221021204126.927603-1-rafaelmendsr@gmail.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Reviewed-by: default avatarSuwan Kim <suwan.kim027@gmail.com>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Acked-by: default avatarJason Wang <jasowang@redhat.com>
parent 72455a11

drivers/block/virtio_blk.c

+4 −2
Original line number Diff line number Diff line
@@ -334,14 +334,16 @@ static blk_status_t virtblk_prep_rq(struct blk_mq_hw_ctx *hctx, 
					struct virtblk_req *vbr)

{

	blk_status_t status;

	int num;



	status = virtblk_setup_cmd(vblk->vdev, req, vbr);

	if (unlikely(status))

		return status;



	vbr->sg_table.nents = virtblk_map_data(hctx, req, vbr);

	if (unlikely(vbr->sg_table.nents < 0))

	num = virtblk_map_data(hctx, req, vbr);

	if (unlikely(num < 0))

		return virtblk_fail_to_queue(req, -ENOMEM);

	vbr->sg_table.nents = num;



	blk_mq_start_request(req);