From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Bart Van Assche To: Jens Axboe Cc: linux-block@vger.kernel.org, Christoph Hellwig , Bart Van Assche , "Michael S . Tsirkin" , Dann Frazier , stable@vger.kernel.org Subject: [PATCH v3] virtio_blk: Fix an SG_IO regression Date: Thu, 26 Oct 2017 07:30:30 +0200 Message-Id: <20171026053030.12456-1-bart.vanassche@wdc.com> List-ID: Avoid that submitting an SG_IO ioctl triggers a kernel oops that is preceded by: usercopy: kernel memory overwrite attempt detected to (null) () (6 bytes) kernel BUG at mm/usercopy.c:72! Reported-by: Dann Frazier Fixes: commit ca18d6f769d2 ("block: Make most scsi_req_init() calls implicit") Signed-off-by: Bart Van Assche Cc: Michael S. Tsirkin Cc: Dann Frazier Cc: # 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