From 508b09046c0f21678652fb66fd1e9959d55591d2 Mon Sep 17 00:00:00 2001 From: Alin Nastac Date: Wed, 21 Nov 2018 14:00:30 +0100 Subject: [PATCH] netfilter: ipv6: Preserve link scope traffic original oif When ip6_route_me_harder is invoked, it resets outgoing interface of: - link-local scoped packets sent by neighbor discovery - multicast packets sent by MLD host - multicast packets send by MLD proxy daemon that sets outgoing interface through IPV6_PKTINFO ipi6_ifindex Link-local and multicast packets must keep their original oif after ip6_route_me_harder is called. Signed-off-by: Alin Nastac Signed-off-by: Pablo Neira Ayuso --- net/ipv6/netfilter.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/ipv6/netfilter.c +++ b/net/ipv6/netfilter.c @@ -24,7 +24,8 @@ int ip6_route_me_harder(struct net *net, unsigned int hh_len; struct dst_entry *dst; struct flowi6 fl6 = { - .flowi6_oif = sk ? sk->sk_bound_dev_if : 0, + .flowi6_oif = sk && sk->sk_bound_dev_if ? sk->sk_bound_dev_if : + rt6_need_strict(&iph->daddr) ? skb_dst(skb)->dev->ifindex : 0, .flowi6_mark = skb->mark, .flowi6_uid = sock_net_uid(net, sk), .daddr = iph->daddr,