On Mon, Mar 28, 2016 at 4:58 PM, Alexander Duyck <adu...@mirantis.com> wrote:
> 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 <adu...@mirantis.com>
> ---
>
> This should allow us to keep the fix that Jesse added without breaking the
> 3 cases that Tom called out in terms of FOU/GUE.
>
> Additional work will be needed in net-next as we probably need to make it
> so that offloads work correctly when we get around to supporting
> NETIF_F_GSO_GRE_CSUM.
>
> net/ipv4/fou.c | 32 ++++++++++++++++++++++++++++++++
> 1 file changed, 32 insertions(+)
>
> diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
> index 4136da9275b2..2c30256ee959 100644
> --- a/net/ipv4/fou.c
> +++ b/net/ipv4/fou.c
> @@ -195,6 +195,22 @@ static struct sk_buff **fou_gro_receive(struct sk_buff
> **head,
> u8 proto = NAPI_GRO_CB(skb)->proto;
> const struct net_offload **offloads;
>
> + switch (proto) {
> + case IPPROTO_IPIP:
> + case IPPROTO_IPV6:
> + case IPPROTO_GRE:
> + /* We can clear the encap_mark for these 3 protocols as
> + * 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;
> + /* fall-through */
> + default:
> + break;
> + }
Switch statement is not needed, just do 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]);
> @@ -359,6 +375,22 @@ static struct sk_buff **gue_gro_receive(struct sk_buff
> **head,
> NAPI_GRO_CB(p)->flush |= NAPI_GRO_CB(p)->flush_id;
> }
>
> + switch (guehdr->proto_ctype) {
> + case IPPROTO_IPIP:
> + case IPPROTO_IPV6:
> + case IPPROTO_GRE:
> + /* We can clear the encap_mark for these 3 protocols as
> + * 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;
> + /* fall-through */
> + default:
> + break;
> + }
> +
Here also.
> rcu_read_lock();
> offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
> ops = rcu_dereference(offloads[guehdr->proto_ctype]);
>
