From: YOSHIFUJI Hideaki / 吉藤英明 <yoshfuji@linux-ipv6.org>
Date: Mon, 10 Sep 2012 18:41:07 +0000 (+0000)
Subject: ipv6: Compare addresses only bits up to the prefix length (RFC6724).
X-Git-Tag: v3.7-rc1~145^2~169
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=91b4b04ff85de9086c959138d747d2808cc83a46;p=platform%2Fkernel%2Flinux-3.10.git

ipv6: Compare addresses only bits up to the prefix length (RFC6724).

Compare bits up to the source address's prefix length only to
allows DNS load balancing to continue to be used as a tie breaker.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 1237d5d..5fd8ec8 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1070,8 +1070,10 @@ static int ipv6_get_saddr_eval(struct net *net,
 		break;
 	case IPV6_SADDR_RULE_PREFIX:
 		/* Rule 8: Use longest matching prefix */
-		score->matchlen = ret = ipv6_addr_diff(&score->ifa->addr,
-						       dst->addr);
+		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
+		if (ret > score->ifa->prefix_len)
+			ret = score->ifa->prefix_len;
+		score->matchlen = ret;
 		break;
 	default:
 		ret = 0;