diff --git a/sys/netinet/in_var.h b/sys/netinet/in_var.h
index 21062115196f..95a4558ef3eb 100644
--- a/sys/netinet/in_var.h
+++ b/sys/netinet/in_var.h
@@ -185,6 +185,7 @@ struct in_multistep {
 do { \
 	struct ifmultiaddr *ifma; \
 \
+	IF_ADDR_LOCK(ifp); \
 	TAILQ_FOREACH(ifma, &((ifp)->if_multiaddrs), ifma_link) { \
 		if (ifma->ifma_addr->sa_family == AF_INET \
 		    && ((struct sockaddr_in *)ifma->ifma_addr)->sin_addr.s_addr == \
@@ -192,6 +193,7 @@ do { \
 			break; \
 	} \
 	(inm) = ifma ? ifma->ifma_protospec : 0; \
+	IF_ADDR_UNLOCK(ifp); \
 } while(0)
 
 /*
diff --git a/sys/netinet6/in6_var.h b/sys/netinet6/in6_var.h
index 6e2be4f5d849..f9431f8e77f2 100644
--- a/sys/netinet6/in6_var.h
+++ b/sys/netinet6/in6_var.h
@@ -543,6 +543,7 @@ struct	in6_multistep {
 /* struct in6_multi *in6m; */					\
 do { \
 	struct ifmultiaddr *ifma; \
+	IF_ADDR_LOCK(ifp); \
 	TAILQ_FOREACH(ifma, &(ifp)->if_multiaddrs, ifma_link) { \
 		if (ifma->ifma_addr->sa_family == AF_INET6 \
 		    && IN6_ARE_ADDR_EQUAL(&((struct sockaddr_in6 *)ifma->ifma_addr)->sin6_addr, \
@@ -550,6 +551,7 @@ do { \
 			break; \
 	} \
 	(in6m) = (struct in6_multi *)(ifma ? ifma->ifma_protospec : 0); \
+	IF_ADDR_UNLOCK(ifp); \
 } while(0)
 
 /*
diff --git a/sys/netinet6/mld6.c b/sys/netinet6/mld6.c
index 4f621816a369..35236da2acd5 100644
--- a/sys/netinet6/mld6.c
+++ b/sys/netinet6/mld6.c
@@ -290,6 +290,7 @@ mld6_input(m, off)
 		if (timer == 0 && mldh->mld_maxdelay)
 			timer = 1;
 
+		IF_ADDR_LOCK(ifp);
 		TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
 			if (ifma->ifma_addr->sa_family != AF_INET6)
 				continue;
@@ -317,6 +318,7 @@ mld6_input(m, off)
 				}
 			}
 		}
+		IF_ADDR_UNLOCK(ifp);
 		break;
 
 	case MLD_LISTENER_REPORT: