From 96dc809514fb2328605198a0602b67554d8cce7b Mon Sep 17 00:00:00 2001 From: Julian Anastasov Date: Sun, 20 Oct 2013 15:43:03 +0300 Subject: [PATCH] ipv6: always prefer rt6i_gateway if present In v3.9 6fd6ce2056de2709 ("ipv6: Do not depend on rt->n in ip6_finish_output2()." changed the behaviour of ip6_finish_output2() such that the recently introduced rt6_nexthop() is used instead of an assigned neighbor. As rt6_nexthop() prefers rt6i_gateway only for gatewayed routes this causes a problem for users like IPVS, xt_TEE and RAW(hdrincl) if they want to use different address for routing compared to the destination address. Another case is when redirect can create RTF_DYNAMIC route without RTF_GATEWAY flag, we ignore the rt6i_gateway in rt6_nexthop(). Fix the above problems by considering the rt6i_gateway if present, so that traffic routed to address on local subnet is not wrongly diverted to the destination address. Thanks to Simon Horman and Phil Oester for spotting the problematic commit. Thanks to Hannes Frederic Sowa for his review and help in testing. Reported-by: Phil Oester Reported-by: Mark Brooks Signed-off-by: Julian Anastasov Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller --- include/net/ip6_route.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h index f525e7038cca..481404abdf65 100644 --- a/include/net/ip6_route.h +++ b/include/net/ip6_route.h @@ -196,7 +196,7 @@ static inline int ip6_skb_dst_mtu(struct sk_buff *skb) static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt, struct in6_addr *dest) { - if (rt->rt6i_flags & RTF_GATEWAY) + if (rt->rt6i_flags & RTF_GATEWAY || !ipv6_addr_any(&rt->rt6i_gateway)) return &rt->rt6i_gateway; return dest; }