[PATCH v3 2/3] vhost: Use vhost_get_used_size() in vhost_vring_set_addr()

[Greg Kurz]

The open-coded computation of the used size doesn't take the event
into account when the VIRTIO_RING_F_EVENT_IDX feature is present.
Fix that by using vhost_get_used_size().

Signed-off-by: Greg Kurz <groug@kaod.org>
---
 drivers/vhost/vhost.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index c3b49975dc28..9d2c225fb518 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1519,8 +1519,7 @@ static long vhost_vring_set_addr(struct vhost_dev *d,
                /* Also validate log access for used ring if enabled. */
                if ((a.flags & (0x1 << VHOST_VRING_F_LOG)) &&
                        !log_access_ok(vq->log_base, a.log_guest_addr,
-                               sizeof *vq->used +
-                               vq->num * sizeof *vq->used->ring))
+                                      vhost_get_used_size(vq, vq->num)))
                        return -EINVAL;
        }