On Mon, Feb 24, 2020 at 10:19:12AM +0000, anton.ivanov@xxxxxxxxxxxxxxxxxx wrote:
> From: Anton Ivanov <anton.ivanov@xxxxxxxxxxxxxxxxxx>
>
> Some of the locally generated frames marked as GSO which
> arrive at virtio_net_hdr_from_skb() have no GSO_TYPE, no
> fragments (data_len = 0) and length significantly shorter
> than the MTU (752 in my experiments).
>
> This is observed on raw sockets reading off vEth interfaces
> in all 4.x and 5.x kernels I tested.
A bit more info on how to reproduce couldn't hurt here.
>
> These frames are reported as invalid while they are in fact
> gso-less frames.
>
> This patch marks the vnet header as no-GSO for them instead
> of reporting it as invalid.
>
> Signed-off-by: Anton Ivanov <anton.ivanov@xxxxxxxxxxxxxxxxxx>
Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
Eric - as you looked at this in the past, would you mind acking please?
> ---
> include/linux/virtio_net.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h
> index 0d1fe9297ac6..94fb78c3a2ab 100644
> --- a/include/linux/virtio_net.h
> +++ b/include/linux/virtio_net.h
> @@ -100,8 +100,8 @@ static inline int virtio_net_hdr_from_skb(const struct sk_buff *skb,
> {
> memset(hdr, 0, sizeof(*hdr)); /* no info leak */
>
> - if (skb_is_gso(skb)) {
> - struct skb_shared_info *sinfo = skb_shinfo(skb);
> + struct skb_shared_info *sinfo = skb_shinfo(skb);
> + if (skb_is_gso(skb) && sinfo->gso_type) {
>
> /* This is a hint as to how much should be linear. */
> hdr->hdr_len = __cpu_to_virtio16(little_endian,
> --
> 2.20.1
_______________________________________________
Virtualization mailing list
Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
