From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ahmed Abdelsalam Subject: [net-next] ipv6:sr: Use the right next-hop value for neighbor discovery in End.DX4 Date: Sat, 25 Aug 2018 16:15:41 +0200 Message-ID: <20180825141541.960-1-amsalam20@gmail.com> Cc: linux-kernel@vger.kernel.org, amsalam20@gmail.com To: davem@davemloft.net, dlebrun@google.com, netdev@vger.kernel.org Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org The SRv6 End.DX4 behaviour supports the use-case of L3VPN, where a FIB lookup in a specific tenant table at the egress PE is not required [1]. In the implementation of the behaviour, after the packet being decapsulated, the lookup in the routing sub-system is done based on next-hop specified form the control plane (using iproute2) or the destination address of the packet. However, the neighbour discovery process always fall back on the destination address of the packet (in ip_finish_output2 ()), if "rt_gateway" value is not present in the "struct rtable rt". nexthop = (__force u32) rt_nexthop(rt, ip_hdr(skb)->daddr); This patch makes sure that "rt_gateway" has the value of the next-hop configured from the control plane. The patch is tested for inner IPv4 packets having destination address different from the next-hop configured using iproute2 [1] https://tools.ietf.org/html/draft-filsfils-spring-srv6-network-programming-05 Signed-off-by: Ahmed Abdelsalam --- net/ipv6/seg6_local.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c index 60325dbfe88b..d346f0d19c09 100644 --- a/net/ipv6/seg6_local.c +++ b/net/ipv6/seg6_local.c @@ -374,6 +374,8 @@ static int input_action_end_dx4(struct sk_buff *skb, if (err) goto drop; + ((struct rtable *)skb_dst(skb))->rt_gateway = nhaddr; + return dst_input(skb); drop: -- 2.11.0