netdev - [PATCH net v2 2/2] ipv6/udp: use sticky pktinfo egress ifindex on connect()

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 29 Jan 2016 12:30:20 +0100
From:	Paolo Abeni <pabeni@...hat.com>
To:	netdev@...r.kernel.org
Cc:	"David S. Miller" <davem@...emloft.net>,
	David Ahern <dsa@...ulusnetworks.com>,
	Hajime Tazaki <thehajime@...il.com>, lucien.xin@...il.com,
	Marcelo Ricardo Leitner <marcelo.leitner@...il.com>,
	Hannes Frederic Sowa <hannes@...essinduktion.org>,
	YOSHIFUJI Hideaki <yoshfuji@...ux-ipv6.org>
Subject: [PATCH net v2 2/2] 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@...hat.com>
---
 net/ipv6/datagram.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 517c55b..4281621 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;
 
-- 
1.8.3.1