Re: [PATCH net] net/tunnel: set inner protocol in network gro hooks

[David Miller <davem@davemloft.net>]

From: Paolo Abeni <pabeni@redhat.com>
Date: Tue,  7 Mar 2017 18:33:31 +0100

> The gso code of several tunnels type (gre and udp tunnels)
> takes for granted that the skb->inner_protocol is properly
> initialized and drops the packet elsewhere.
> 
> On the forwarding path no one is initializing such field,
> so gro encapsulated packets are dropped on forward.
> 
> Since commit 38720352412a ("gre: Use inner_proto to obtain
> inner header protocol"), this can be reproduced when the
> encapsulated packets use gre as the tunneling protocol.
> 
> The issue happens also with vxlan and geneve tunnels since
> commit 8bce6d7d0d1e ("udp: Generalize skb_udp_segment"), if the
> forwarding host's ingress nic has h/w offload for such tunnel
> and a vxlan/geneve device is configured on top of it, regardless
> of the configured peer address and vni.
> 
> To address the issue, this change initialize the inner_protocol
> field for encapsulated packets in both ipv4 and ipv6 gro complete
> callbacks.
> 
> Fixes: 38720352412a ("gre: Use inner_proto to obtain inner header protocol")
> Fixes: 8bce6d7d0d1e ("udp: Generalize skb_udp_segment")
> Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Applied and queued up for -stable.