ipv4: fix tunneled VM traffic over hw VXLAN/GRE GSO NIC
VM to VM GSO traffic is broken if it goes through VXLAN or GRE
tunnel and the physical NIC on the host supports hardware VXLAN/GRE
GSO offload (e.g. bnx2x and next-gen mlx4).
Two issues -
(VXLAN) VM traffic has SKB_GSO_DODGY and SKB_GSO_UDP_TUNNEL with
SKB_GSO_TCP/UDP set depending on the inner protocol. GSO header
integrity check fails in udp4_ufo_fragment if inner protocol is
TCP. Also gso_segs is calculated incorrectly using skb->len that
includes tunnel header. Fix: robust check should only be applied
to the inner packet.
(VXLAN & GRE) Once GSO header integrity check passes, NULL segs
is returned and the original skb is sent to hardware. However the
tunnel header is already pulled. Fix: tunnel header needs to be
restored so that hardware can perform GSO properly on the original
packet.
Signed-off-by: Wei-Chun Chao <weichunc@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 7514b9c..5faaadb 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3017,6 +3017,19 @@
dev->gso_max_size = size;
}
+static inline void skb_gso_error_unwind(struct sk_buff *skb, __be16 protocol,
+ int pulled_hlen, u16 mac_offset,
+ int mac_len)
+{
+ skb->protocol = protocol;
+ skb->encapsulation = 1;
+ skb_push(skb, pulled_hlen);
+ skb_reset_transport_header(skb);
+ skb->mac_header = mac_offset;
+ skb->network_header = skb->mac_header + mac_len;
+ skb->mac_len = mac_len;
+}
+
static inline bool netif_is_macvlan(struct net_device *dev)
{
return dev->priv_flags & IFF_MACVLAN;