diff mbox series

[v7,1/8] virtio-blk: store opt_io_size with correct size

Message ID 20200528213946.1636444-2-rvkagan@yandex-team.ru (mailing list archive)
State New, archived
Headers show
Series block: enhance handling of size-related BlockConf properties | expand

Commit Message

Roman Kagan May 28, 2020, 9:39 p.m. UTC 
The width of opt_io_size in virtio_blk_config is 32bit.  However, it's
written with virtio_stw_p; this may result in value truncation, and on
big-endian systems with legacy virtio in completely bogus readings in
the guest.

Use the appropriate accessor to store it.

Signed-off-by: Roman Kagan <rvkagan@yandex-team.ru>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
v4 -> v5:
- split out into separate patch [Philippe]

 hw/block/virtio-blk.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index f5f6fc925e..413083e62f 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -918,7 +918,7 @@  static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
     virtio_stw_p(vdev, &blkcfg.geometry.cylinders, conf->cyls);
     virtio_stl_p(vdev, &blkcfg.blk_size, blk_size);
     virtio_stw_p(vdev, &blkcfg.min_io_size, conf->min_io_size / blk_size);
-    virtio_stw_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size);
+    virtio_stl_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size);
     blkcfg.geometry.heads = conf->heads;
     /*
      * We must ensure that the block device capacity is a multiple of