virtio_blk: Fix an SG_IO regression

Avoid that submitting an SG_IO ioctl triggers a kernel oops that
is preceded by:

usercopy: kernel memory overwrite attempt detected to (null) (<null>) (6 bytes)
kernel BUG at mm/usercopy.c:72!

Reported-by: Dann Frazier <dann.frazier@canonical.com>
Fixes: commit ca18d6f769 ("block: Make most scsi_req_init() calls implicit")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: <stable@vger.kernel.org> # v4.13
Reviewed-by: Christoph Hellwig <hch@lst.de>

Moved virtblk_initialize_rq() inside CONFIG_VIRTIO_BLK_SCSI.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Bart Van Assche 2017-10-27 08:23:21 -06:00 committed by Jens Axboe
parent 93689a6031
commit efea2abcb0

View File

@ -593,10 +593,22 @@ static int virtblk_map_queues(struct blk_mq_tag_set *set)
return blk_mq_virtio_map_queues(set, vblk->vdev, 0);
}
#ifdef CONFIG_VIRTIO_BLK_SCSI
static void virtblk_initialize_rq(struct request *req)
{
struct virtblk_req *vbr = blk_mq_rq_to_pdu(req);
scsi_req_init(&vbr->sreq);
}
#endif
static const struct blk_mq_ops virtio_mq_ops = {
.queue_rq = virtio_queue_rq,
.complete = virtblk_request_done,
.init_request = virtblk_init_request,
#ifdef CONFIG_VIRTIO_BLK_SCSI
.initialize_rq_fn = virtblk_initialize_rq,
#endif
.map_queues = virtblk_map_queues,
};