From: Jiri Pirko <jpirko@redhat.com>
Date: Tue, 21 Apr 2009 14:49:27 +0200
Subject: [net] ipv6: assume loopback address in link-local scope
Message-id: 20090421124927.GA13494@psychotron.englab.brq.redhat.com
O-Subject: [RHEL5.4 patch] BZ487233 net: ipv6: Assume the loopback address in link-local scope.
Bugzilla: 487233
RH-Acked-by: David Miller <davem@redhat.com>
RH-Acked-by: Anton Arapov <aarapov@redhat.com>
RH-Acked-by: Rik van Riel <riel@redhat.com>
RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com>

BZ487233
https://bugzilla.redhat.com/show_bug.cgi?id=487233

Description:
Handle interface property strictly when looking up a route for the loopback
address (RFC4291 2.5.3):

"An IPv6 packet with a destination address of loopback must never be sent
outside of a single node and must never be forwarded by an IPv6 router."

This is direct upstream backport. It replaces previously posted patch for
bz487233 which covered only UDP. DonZ, please remove previous version from
your tracking.

Upstream:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=5ce83afaac956238c3c25f60a899c511e9d8cbf4

Brew:
https://brewweb.devel.redhat.com/taskinfo?taskID=1769077

Test:
Booted on x86_64, tested with the attached reproducer.

Jirka

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index ca3c300..616f682 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -239,7 +239,7 @@ static __inline__ int rt6_check_expired(const struct rt6_info *rt)
 static inline int rt6_need_strict(struct in6_addr *daddr)
 {
 	return (ipv6_addr_type(daddr) &
-		(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
+		(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK));
 }
 
 /*