1 files changed, 20 insertions, 1 deletions
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index 2688f3e82165..fc5000370030 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -229,6 +229,25 @@ static bool icmpv6_xrlim_allow(struct sock *sk, u8 type,
 	return res;
 }
 
+static bool icmpv6_rt_has_prefsrc(struct sock *sk, u8 type,
+				  struct flowi6 *fl6)
+{
+	struct net *net = sock_net(sk);
+	struct dst_entry *dst;
+	bool res = false;
+
+	dst = ip6_route_output(net, sk, fl6);
+	if (!dst->error) {
+		struct rt6_info *rt = (struct rt6_info *)dst;
+		struct in6_addr prefsrc;
+
+		rt6_get_prefsrc(rt, &prefsrc);
+		res = !ipv6_addr_any(&prefsrc);
+	}
+	dst_release(dst);
+	return res;
+}
+
 /*
  *	an inline helper for the "simple" if statement below
  *	checks if parameter problem report is caused by an
@@ -527,7 +546,7 @@ static void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info,
 		saddr = force_saddr;
 	if (saddr) {
 		fl6.saddr = *saddr;
-	} else {
+	} else if (!icmpv6_rt_has_prefsrc(sk, type, &fl6)) {
 		/* select a more meaningful saddr from input if */
 		struct net_device *in_netdev;