Commit f1d4884d authored Feb 25, 2020 by Yuya Kusakabe Committed by Daniel Borkmann Feb 25, 2020

virtio_net: Keep vnet header zeroed if XDP is loaded for small buffer



We do not want to care about the vnet header in receive_small() if XDP
is loaded, since we can not know whether or not the packet is modified
by XDP.

Fixes: f6b10209 ("virtio-net: switch to use build_skb() for small buffer")
Signed-off-by: Yuya Kusakabe <yuya.kusakabe@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/bpf/20200225033212.437563-1-yuya.kusakabe@gmail.com

parent 9fb156bb

drivers/net/virtio_net.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -735,10 +735,10 @@ static struct sk_buff receive_small(struct net_device dev,
		}
		skb_reserve(skb, headroom - delta);
		skb_put(skb, len);
		if (!delta) {
		if (!xdp_prog) {
		buf += header_offset;
		memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
		} /* keep zeroed vnet hdr since packet was changed by bpf */
		} /* keep zeroed vnet hdr since XDP is loaded */

		err:
		return skb;

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