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@xxxxxxxxxxxxx>
Fixes: commit ca18d6f769d2 ("block: Make most scsi_req_init() calls implicit")
Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx>
Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
Cc: Dann Frazier <dann.frazier@xxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v4.13
---
drivers/block/virtio_blk.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 34e17ee799be..b44f5b7e68f6 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -593,10 +593,18 @@ static int virtblk_map_queues(struct blk_mq_tag_set *set)
return blk_mq_virtio_map_queues(set, vblk->vdev, 0);
}
+static void virtblk_initialize_rq(struct request *req)
+{
+ struct virtblk_req *vbr = blk_mq_rq_to_pdu(req);
+
+ scsi_req_init(&vbr->sreq);
+}
+
static const struct blk_mq_ops virtio_mq_ops = {
.queue_rq = virtio_queue_rq,
.complete = virtblk_request_done,
.init_request = virtblk_init_request,
+ .initialize_rq_fn = virtblk_initialize_rq,
.map_queues = virtblk_map_queues,
};
--
2.14.2