Message ID | 20211129030841.3611-2-jasowang@redhat.com |
---|---|
State | New |
Headers | show |
Series | [V2,1/2] virtio-balloon: process all in sgs for free_page_vq | expand |
On 29.11.21 04:08, Jason Wang wrote: > Spec said: > > "and len the total of bytes written into the buffer." > > For inflateq, deflateq and statsq, we don't process in_sg so the used > length should be zero. For free_page_vq, tough the pages could be s/tough/though/ > changed by the device (in the destination), spec said: > > "Note: len is particularly useful for drivers using untrusted buffers: > if a driver does not know exactly how much has been written by the > device, the driver would have to zero the buffer in advance to ensure > no data leakage occurs." > > So 0 should be used as well here. > > Signed-off-by: Jason Wang <jasowang@redhat.com> > --- > Changes since V1: > - use 0 as used length for free_page_vq > --- > hw/virtio/virtio-balloon.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c > index 17de2558cb..9a4f491b54 100644 > --- a/hw/virtio/virtio-balloon.c > +++ b/hw/virtio/virtio-balloon.c > @@ -231,7 +231,7 @@ static void balloon_stats_poll_cb(void *opaque) > return; > } > > - virtqueue_push(s->svq, s->stats_vq_elem, s->stats_vq_offset); > + virtqueue_push(s->svq, s->stats_vq_elem, 0); > virtio_notify(vdev, s->svq); > g_free(s->stats_vq_elem); > s->stats_vq_elem = NULL; > @@ -438,7 +438,7 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) > memory_region_unref(section.mr); > } > > - virtqueue_push(vq, elem, offset); > + virtqueue_push(vq, elem, 0); > virtio_notify(vdev, vq); > g_free(elem); > virtio_balloon_pbp_free(&pbp); > @@ -552,7 +552,7 @@ static bool get_free_page_hints(VirtIOBalloon *dev) > } > > out: > - virtqueue_push(vq, elem, 1); > + virtqueue_push(vq, elem, 0); > g_free(elem); > return ret; > } > Reviewed-by: David Hildenbrand <david@redhat.com>
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index 17de2558cb..9a4f491b54 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -231,7 +231,7 @@ static void balloon_stats_poll_cb(void *opaque) return; } - virtqueue_push(s->svq, s->stats_vq_elem, s->stats_vq_offset); + virtqueue_push(s->svq, s->stats_vq_elem, 0); virtio_notify(vdev, s->svq); g_free(s->stats_vq_elem); s->stats_vq_elem = NULL; @@ -438,7 +438,7 @@ static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq) memory_region_unref(section.mr); } - virtqueue_push(vq, elem, offset); + virtqueue_push(vq, elem, 0); virtio_notify(vdev, vq); g_free(elem); virtio_balloon_pbp_free(&pbp); @@ -552,7 +552,7 @@ static bool get_free_page_hints(VirtIOBalloon *dev) } out: - virtqueue_push(vq, elem, 1); + virtqueue_push(vq, elem, 0); g_free(elem); return ret; }
Spec said: "and len the total of bytes written into the buffer." For inflateq, deflateq and statsq, we don't process in_sg so the used length should be zero. For free_page_vq, tough the pages could be changed by the device (in the destination), spec said: "Note: len is particularly useful for drivers using untrusted buffers: if a driver does not know exactly how much has been written by the device, the driver would have to zero the buffer in advance to ensure no data leakage occurs." So 0 should be used as well here. Signed-off-by: Jason Wang <jasowang@redhat.com> --- Changes since V1: - use 0 as used length for free_page_vq --- hw/virtio/virtio-balloon.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)