virtio_net: reject XDP programs using header adjustment

commit 17bedab27231 ("bpf: xdp: Allow head adjustment in XDP prog")
added a new XDP helper to prepend and remove data from a frame.
Make virtio_net reject programs making use of this helper until
proper support is added.

Signed-off-by: Jakub Kicinski <[email protected]>
Acked-by: John Fastabend <[email protected]>
Acked-by: Jason Wang <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 4c6e9b43f1d3aa9c3c90c0d75110c9752ee0f3b4..765c2d6358daf38203cdb1a50a31cc04f65c1968 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1715,6 +1715,11 @@ static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog)
        u16 xdp_qp = 0, curr_qp;
        int i, err;
 
+       if (prog && prog->xdp_adjust_head) {
+               netdev_warn(dev, "Does not support bpf_xdp_adjust_head()\n");
+               return -EOPNOTSUPP;
+       }
+
        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_ECN) ||