From f1d4884d6871ded0592604b0e72e4a7bd292eab9 Mon Sep 17 00:00:00 2001 From: Yuya Kusakabe Date: Tue, 25 Feb 2020 12:32:11 +0900 Subject: [PATCH] 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: f6b10209b90d ("virtio-net: switch to use build_skb() for small buffer") Signed-off-by: Yuya Kusakabe Signed-off-by: Daniel Borkmann Acked-by: Jason Wang Acked-by: Michael S. Tsirkin Link: https://lore.kernel.org/bpf/20200225033212.437563-1-yuya.kusakabe@gmail.com --- drivers/net/virtio_net.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 2fe7a3188282..f39d0218bdaa 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -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; -- 2.11.0