From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Frederic Sowa Subject: Re: [PATCH net-next] net: ipv4: Add ability to have GRE ignore DF bit in IPv4 payloads Date: Tue, 07 Jun 2016 22:23:42 +0200 Message-ID: <1465331022.134529.630880921.787BED73@webmail.messagingengine.com> References: <20160607194846.11494-1-philipp@redfish-solutions.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Stephen Hemminger To: Philip Prindeville , netdev@vger.kernel.org Return-path: Received: from out2-smtp.messagingengine.com ([66.111.4.26]:40413 "EHLO out2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161315AbcFGUXn (ORCPT ); Tue, 7 Jun 2016 16:23:43 -0400 In-Reply-To: <20160607194846.11494-1-philipp@redfish-solutions.com> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, Jun 7, 2016, at 21:48, Philip Prindeville wrote: > static struct rtnl_link_ops ipgre_link_ops __read_mostly = { > diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c > index d8f5e0a..95649eb 100644 > --- a/net/ipv4/ip_tunnel.c > +++ b/net/ipv4/ip_tunnel.c > @@ -682,7 +682,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct > net_device *dev, > } > > df = tnl_params->frag_off; > - if (skb->protocol == htons(ETH_P_IP)) > + if (skb->protocol == htons(ETH_P_IP) && !tunnel->ignore_df) > df |= (inner_iph->frag_off&htons(IP_DF)); > > max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr) Is still enforce that we inherit the ttl from the inner header to the outer header if we don't set df bit? Thanks, Hannes