From 300cdd3c94d10f3e06bc22f78385b446ea581232 Mon Sep 17 00:00:00 2001
From: Bruce M Simpson <bms@FreeBSD.org>
Date: Tue, 27 Apr 2010 13:27:51 +0000
Subject: [PATCH] MFC 206454:   When embedding the scope ID in MLDv1 output,
 check if the scope of the address   being embedded is in fact link-local,
 before attempting to embed it.

  Note that this operation is a side-effect of trying to avoid recursion on
  the IN6 scope lock.

PR:		144560
Submitted by:	Petr Lampa
---
 sys/netinet6/mld6.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/sys/netinet6/mld6.c b/sys/netinet6/mld6.c
index cade0d2b208..21d9eabe363 100644
--- a/sys/netinet6/mld6.c
+++ b/sys/netinet6/mld6.c
@@ -195,8 +195,10 @@ static int	sysctl_mld_ifinfo(SYSCTL_HANDLER_ARGS);
 static struct mtx		 mld_mtx;
 MALLOC_DEFINE(M_MLD, "mld", "mld state");
 
-#define	MLD_EMBEDSCOPE(pin6, zoneid) \
-	(pin6)->s6_addr16[1] = htons((zoneid) & 0xFFFF)
+#define	MLD_EMBEDSCOPE(pin6, zoneid)					\
+	if (IN6_IS_SCOPE_LINKLOCAL(pin6) ||				\
+	    IN6_IS_ADDR_MC_INTFACELOCAL(pin6))				\
+		(pin6)->s6_addr16[1] = htons((zoneid) & 0xFFFF)		\
 
 /*
  * VIMAGE-wide globals.