From c3483384ee511ee2af40b4076366cd82a6a47b86 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Tue, 29 Mar 2016 14:55:22 -0700 Subject: [PATCH] gro: Allow tunnel stacking in the case of FOU/GUE This patch should fix the issues seen with a recent fix to prevent tunnel-in-tunnel frames from being generated with GRO. The fix itself is correct for now as long as we do not add any devices that support NETIF_F_GSO_GRE_CSUM. When such a device is added it could have the potential to mess things up due to the fact that the outer transport header points to the outer UDP header and not the GRE header as would be expected. Fixes: fac8e0f579695 ("tunnels: Don't apply GRO to multiple layers of encapsulation.") Signed-off-by: Alexander Duyck Signed-off-by: David S. Miller --- net/ipv4/fou.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c index a0586b4a197d..5a94aea280d3 100644 --- a/net/ipv4/fou.c +++ b/net/ipv4/fou.c @@ -195,6 +195,14 @@ static struct sk_buff **fou_gro_receive(struct sk_buff **head, u8 proto = NAPI_GRO_CB(skb)->proto; const struct net_offload **offloads; + /* We can clear the encap_mark for FOU as we are essentially doing + * one of two possible things. We are either adding an L4 tunnel + * header to the outer L3 tunnel header, or we are are simply + * treating the GRE tunnel header as though it is a UDP protocol + * specific header such as VXLAN or GENEVE. + */ + NAPI_GRO_CB(skb)->encap_mark = 0; + rcu_read_lock(); offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads; ops = rcu_dereference(offloads[proto]); @@ -352,6 +360,14 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head, } } + /* We can clear the encap_mark for GUE as we are essentially doing + * one of two possible things. We are either adding an L4 tunnel + * header to the outer L3 tunnel header, or we are are simply + * treating the GRE tunnel header as though it is a UDP protocol + * specific header such as VXLAN or GENEVE. + */ + NAPI_GRO_CB(skb)->encap_mark = 0; + rcu_read_lock(); offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads; ops = rcu_dereference(offloads[guehdr->proto_ctype]);