From: Bart Van Assche <bart.vanassche@wdc.com>
Date: Fri, 27 Oct 2017 08:23:21 -0600
Subject: [PATCH] virtio_blk: Fix an SG_IO regression
Patch-mainline: v4.14-rc8
Git-commit: efea2abcb03215f2efadfe994ff7f652aaff196b
References: bsc#1085636
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 ca18d6f769d2 ("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>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
---
drivers/block/virtio_blk.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 34e17ee799be..68846897d213 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -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,
};
--
2.12.3