From: Paolo Abeni <pabeni@redhat.com>
Date: Fri, 29 Jan 2016 11:30:20 +0000 (+0100)
Subject: ipv6/udp: use sticky pktinfo egress ifindex on connect()
X-Git-Tag: v4.5-rc3~21^2~4^2
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=1cdda91871470f15e79375991bd2eddc6e86ddb1;p=users%2Fjedix%2Flinux-maple.git

ipv6/udp: use sticky pktinfo egress ifindex on connect()

Currently, the egress interface index specified via IPV6_PKTINFO
is ignored by __ip6_datagram_connect(), so that RFC 3542 section 6.7
can be subverted when the user space application calls connect()
before sendmsg().
Fix it by initializing properly flowi6_oif in connect() before
performing the route lookup.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 517c55b01ba8..428162155280 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -162,6 +162,9 @@ ipv4_connected:
 	fl6.fl6_dport = inet->inet_dport;
 	fl6.fl6_sport = inet->inet_sport;
 
+	if (!fl6.flowi6_oif)
+		fl6.flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
+
 	if (!fl6.flowi6_oif && (addr_type&IPV6_ADDR_MULTICAST))
 		fl6.flowi6_oif = np->mcast_oif;