From 2703c9ba28276575c15656af63a859377bf89f1e Mon Sep 17 00:00:00 2001
From: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Date: Tue, 4 Dec 2012 01:03:07 +0000
Subject: [PATCH] --- yaml --- r: 341892 b: refs/heads/master c:
 8caaf7b608ae27f7e7d5f5df6f87039db556d4bb h: refs/heads/master v: v3

---
 [refs]                 |  2 +-
 trunk/net/ipv4/route.c | 23 +++++++++++++++++++++--
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 7db6534dbc72..a8d7faed89a2 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: e3d8fabee3b66ce158b2603f270479b84b6e4ba7
+refs/heads/master: 8caaf7b608ae27f7e7d5f5df6f87039db556d4bb
diff --git a/trunk/net/ipv4/route.c b/trunk/net/ipv4/route.c
index baa9b289d7ab..844a9ef60dbd 100644
--- a/trunk/net/ipv4/route.c
+++ b/trunk/net/ipv4/route.c
@@ -2232,8 +2232,27 @@ static int rt_fill_info(struct net *net,  __be32 dst, __be32 src,
 	error = rt->dst.error;
 
 	if (rt_is_input_route(rt)) {
-		if (nla_put_u32(skb, RTA_IIF, rt->rt_iif))
-			goto nla_put_failure;
+#ifdef CONFIG_IP_MROUTE
+		if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) &&
+		    IPV4_DEVCONF_ALL(net, MC_FORWARDING)) {
+			int err = ipmr_get_route(net, skb,
+						 fl4->saddr, fl4->daddr,
+						 r, nowait);
+			if (err <= 0) {
+				if (!nowait) {
+					if (err == 0)
+						return 0;
+					goto nla_put_failure;
+				} else {
+					if (err == -EMSGSIZE)
+						goto nla_put_failure;
+					error = err;
+				}
+			}
+		} else
+#endif
+			if (nla_put_u32(skb, RTA_IIF, rt->rt_iif))
+				goto nla_put_failure;
 	}
 
 	if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, error) < 0)