On Tue, Mar 29, 2016 at 2:13 PM, Tom Herbert <t...@herbertland.com> wrote:
> 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]);
>>
Okay, I can update that and submit a v2. The only real reason why I
had the switch statements was out of an abundance of caution since
those were the only 3 cases where I knew we would run into issues.
- Alex
