From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Ricardo Leitner Subject: [PATCH stable] ipv6: restrict neighbor entry creation to output flow Date: Wed, 14 Aug 2013 10:53:27 -0300 Message-ID: Cc: hannes@stressinduktion.org, jiri@resnulli.us, dbanerje@akamai.com, yoshfuji@linux-ipv6.org To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:20554 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932317Ab3HNNyD (ORCPT ); Wed, 14 Aug 2013 09:54:03 -0400 Sender: netdev-owner@vger.kernel.org List-ID: This patch is based on 3.2.y branch, the one used by reported. Please let me know if it should be different. Thanks. ---8<--- Commit 0d6a77079c475033cb622c07c5a880b392ef664e introduced a regression on which routes to local delivery would not work anymore. Like this: $ ip -6 route add local 2001::/64 dev lo $ ping6 -c1 2001::9 PING 2001::9(2001::9) 56 data bytes ping: sendmsg: Invalid argument As this is a local delivery, that commit would not allow the creation of a neighbor entry and thus the packet cannot be sent. But as TPROXY scenario actually needs to avoid the neighbor entry creation only for input flow, this patch now limits previous patch to input flow, keeping output as before that patch. Reported-by: Debabrata Banerjee Signed-off-by: Marcelo Ricardo Leitner CC: Hannes Frederic Sowa --- net/ipv6/route.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 18ea73c..bc9103d 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -791,7 +791,7 @@ static struct rt6_info *rt6_alloc_clone(struct rt6_info *ort, } static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif, - struct flowi6 *fl6, int flags) + struct flowi6 *fl6, int flags, bool input) { struct fib6_node *fn; struct rt6_info *rt, *nrt; @@ -799,8 +799,11 @@ static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int attempts = 3; int err; int reachable = net->ipv6.devconf_all->forwarding ? 0 : RT6_LOOKUP_F_REACHABLE; + int local = RTF_NONEXTHOP; strict |= flags & RT6_LOOKUP_F_IFACE; + if (input) + local |= RTF_LOCAL; relookup: read_lock_bh(&table->tb6_lock); @@ -820,7 +823,7 @@ restart: read_unlock_bh(&table->tb6_lock); if (!dst_get_neighbour_raw(&rt->dst) - && !(rt->rt6i_flags & (RTF_NONEXTHOP | RTF_LOCAL))) + && !(rt->rt6i_flags & local)) nrt = rt6_alloc_cow(rt, &fl6->daddr, &fl6->saddr); else if (!(rt->dst.flags & DST_HOST)) nrt = rt6_alloc_clone(rt, &fl6->daddr); @@ -864,7 +867,7 @@ out2: static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table, struct flowi6 *fl6, int flags) { - return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags); + return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags, true); } void ip6_route_input(struct sk_buff *skb) @@ -890,7 +893,7 @@ void ip6_route_input(struct sk_buff *skb) static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table, struct flowi6 *fl6, int flags) { - return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags); + return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags, false); } struct dst_entry * ip6_route_output(struct net *net, const struct sock *sk, -- 1.8.3.1