From: Bjørn Mork <bjorn@mork.no>
Date: Tue, 5 Jul 2011 23:04:13 +0000 (+0000)
Subject: Disable router anycast address for /127 prefixes
X-Git-Tag: v3.1-rc1~316^2~209
X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=2bda8a0c8af5294b869da1efd2c2b9a562f50dcf

Disable router anycast address for /127 prefixes

RFC 6164 requires that routers MUST disable Subnet-Router anycast
for the prefix when /127 prefixes are used.

No need for matching code in addrconf_leave_anycast() as it
will silently ignore any attempt to leave an unknown anycast
address.

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 05838c7fcf64..fc6d37723664 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1470,6 +1470,8 @@ void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
 {
 	struct in6_addr addr;
+	if (ifp->prefix_len == 127) /* RFC 6164 */
+		return;
 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
 	if (ipv6_addr_any(&addr))
 		return;