Re: [PATCH net 7/9] virtio-net: forbid XDP when VIRTIO_NET_F_GUEST_UFO is support

[John Fastabend]

On 16-12-23 06:37 AM, Jason Wang wrote:
> When VIRTIO_NET_F_GUEST_UFO is negotiated, host could still send UFO
> packet that exceeds a single page which could not be handled
> correctly by XDP. So this patch forbids setting XDP when GUEST_UFO is
> supported. While at it, forbid XDP for ECN (which comes only from GRO)
> too to prevent user from misconfiguration.
> 
> Cc: John Fastabend <john.r.fastabend@xxxxxxxxx>
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
> ---
>  drivers/net/virtio_net.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 77ae358..c1f66d8 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -1684,7 +1684,9 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog)
>  	int i, err;
>  
>  	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
> -	    virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6)) {
> +	    virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
> +	    virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
> +	    virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO)) {
>  		netdev_warn(dev, "can't set XDP while host is implementing LRO, disable LRO first\n");
>  		return -EOPNOTSUPP;
>  	}
> 

Acked-by: John Fastabend <john.r.fastabend@xxxxxxxxx>