From: mpi <mpi@openbsd.org>
Date: Wed, 17 Dec 2014 09:45:59 +0000 (+0000)
Subject: Use an interface index instead of a pointer for multicast options.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=ec0be06b6d983c7080de92e271b00734845072fd;p=openbsd

Use an interface index instead of a pointer for multicast options.

Output interface (port) selection for multicast traffic is not done via
route lookups.  Instead the output ifp is registred when setsockopt(2)
is called with the IP{V6,}_MULTICAST_IF option.  But since there is no
mechanism to invalidate such pointer stored in a pcb when an interface
is destroyed/removed, it might lead your kernel to fault.

Prevent a fault upon resume reported by frantisek holop, thanks!

ok mikeb@, claudio@
---

diff --git a/sys/net/if.c b/sys/net/if.c
index bcb7fbd613f..5008933b403 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if.c,v 1.306 2014/12/08 10:46:14 mpi Exp $	*/
+/*	$OpenBSD: if.c,v 1.307 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $	*/
 
 /*
@@ -533,11 +533,6 @@ do { \
 #endif
 #undef IF_DETACH_QUEUES
 
-	/*
-	 * XXX transient ifp refs?  inpcb.ip_moptions.imo_multicast_ifp?
-	 * Other network stacks than INET?
-	 */
-
 	/* Remove the interface from the list of all interfaces.  */
 	TAILQ_REMOVE(&ifnet, ifp, if_list);
 	if (ISSET(ifp->if_xflags, IFXF_TXREADY))
diff --git a/sys/net/if_pfsync.c b/sys/net/if_pfsync.c
index 82500e09c98..0653b4cb8fa 100644
--- a/sys/net/if_pfsync.c
+++ b/sys/net/if_pfsync.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_pfsync.c,v 1.212 2014/11/23 07:39:02 deraadt Exp $	*/
+/*	$OpenBSD: if_pfsync.c,v 1.213 2014/12/17 09:45:59 mpi Exp $	*/
 
 /*
  * Copyright (c) 2002 Michael Shalayeff
@@ -1354,7 +1354,7 @@ pfsyncioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
 			if (imo->imo_num_memberships > 0) {
 				in_delmulti(imo->imo_membership[
 				    --imo->imo_num_memberships]);
-				imo->imo_multicast_ifp = NULL;
+				imo->imo_ifidx = 0;
 			}
 			splx(s);
 			break;
@@ -1379,7 +1379,7 @@ pfsyncioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
 
 		if (imo->imo_num_memberships > 0) {
 			in_delmulti(imo->imo_membership[--imo->imo_num_memberships]);
-			imo->imo_multicast_ifp = NULL;
+			imo->imo_ifidx = 0;
 		}
 
 		if (sc->sc_sync_if &&
@@ -1401,7 +1401,7 @@ pfsyncioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
 				return (ENOBUFS);
 			}
 			imo->imo_num_memberships++;
-			imo->imo_multicast_ifp = sc->sc_sync_if;
+			imo->imo_ifidx = sc->sc_sync_if->if_index;
 			imo->imo_multicast_ttl = PFSYNC_DFLTTL;
 			imo->imo_multicast_loop = 0;
 		}
diff --git a/sys/net/if_vxlan.c b/sys/net/if_vxlan.c
index 947e9d555e9..6e6b330ff65 100644
--- a/sys/net/if_vxlan.c
+++ b/sys/net/if_vxlan.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_vxlan.c,v 1.17 2014/12/05 15:50:04 mpi Exp $	*/
+/*	$OpenBSD: if_vxlan.c,v 1.18 2014/12/17 09:45:59 mpi Exp $	*/
 
 /*
  * Copyright (c) 2013 Reyk Floeter <reyk@openbsd.org>
@@ -179,8 +179,9 @@ vxlan_multicast_cleanup(struct ifnet *ifp)
 {
 	struct vxlan_softc	*sc = (struct vxlan_softc *)ifp->if_softc;
 	struct ip_moptions	*imo = &sc->sc_imo;
-	struct ifnet		*mifp = imo->imo_multicast_ifp;
+	struct ifnet		*mifp;
 
+	mifp = if_get(imo->imo_ifidx);
 	if (mifp != NULL) {
 		if (sc->sc_ahcookie != NULL) {
 			hook_disestablish(mifp->if_addrhooks, sc->sc_ahcookie);
@@ -200,7 +201,7 @@ vxlan_multicast_cleanup(struct ifnet *ifp)
 
 	if (imo->imo_num_memberships > 0) {
 		in_delmulti(imo->imo_membership[--imo->imo_num_memberships]);
-		imo->imo_multicast_ifp = NULL;
+		imo->imo_ifidx = 0;
 	}
 }
 
@@ -229,7 +230,7 @@ vxlan_multicast_join(struct ifnet *ifp, struct sockaddr_in *src,
 		return (ENOBUFS);
 
 	imo->imo_num_memberships++;
-	imo->imo_multicast_ifp = mifp;
+	imo->imo_ifidx = mifp->if_index;
 	if (sc->sc_ttl > 0)
 		imo->imo_multicast_ttl = sc->sc_ttl;
 	else
diff --git a/sys/netinet/igmp.c b/sys/netinet/igmp.c
index 81c56d62f5c..90254fc5cf1 100644
--- a/sys/netinet/igmp.c
+++ b/sys/netinet/igmp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: igmp.c,v 1.46 2014/11/18 02:37:31 tedu Exp $	*/
+/*	$OpenBSD: igmp.c,v 1.47 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$NetBSD: igmp.c,v 1.15 1996/02/13 23:41:25 christos Exp $	*/
 
 /*
@@ -641,7 +641,7 @@ igmp_sendpkt(struct in_multi *inm, int type, in_addr_t addr)
 	m->m_data -= sizeof(struct ip);
 	m->m_len += sizeof(struct ip);
 
-	imo.imo_multicast_ifp = if_get(inm->inm_ifidx);
+	imo.imo_ifidx = inm->inm_ifidx;
 	imo.imo_multicast_ttl = 1;
 
 	/*
diff --git a/sys/netinet/in_pcb.c b/sys/netinet/in_pcb.c
index 11e0938837e..c31e90c5c36 100644
--- a/sys/netinet/in_pcb.c
+++ b/sys/netinet/in_pcb.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in_pcb.c,v 1.164 2014/12/05 15:50:04 mpi Exp $	*/
+/*	$OpenBSD: in_pcb.c,v 1.165 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$NetBSD: in_pcb.c,v 1.25 1996/02/13 23:41:53 christos Exp $	*/
 
 /*
@@ -871,7 +871,7 @@ in_selectsrc(struct in_addr **insrc, struct sockaddr_in *sin,
 	if (IN_MULTICAST(sin->sin_addr.s_addr) && mopts != NULL) {
 		struct ifnet *ifp;
 
-		ifp = mopts->imo_multicast_ifp;
+		ifp = if_get(mopts->imo_ifidx);
 		if (ifp != NULL) {
 			if (ifp->if_rdomain == rtable_l2(rtableid))
 				IFP_TO_IA(ifp, ia);
diff --git a/sys/netinet/ip_carp.c b/sys/netinet/ip_carp.c
index 9d823a6e119..fe32f214c5f 100644
--- a/sys/netinet/ip_carp.c
+++ b/sys/netinet/ip_carp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_carp.c,v 1.240 2014/12/05 15:50:04 mpi Exp $	*/
+/*	$OpenBSD: ip_carp.c,v 1.241 2014/12/17 09:45:59 mpi Exp $	*/
 
 /*
  * Copyright (c) 2002 Michael Shalayeff. All rights reserved.
@@ -1643,7 +1643,7 @@ carp_multicast_cleanup(struct carp_softc *sc)
 		}
 	}
 	imo->imo_num_memberships = 0;
-	imo->imo_multicast_ifp = NULL;
+	imo->imo_ifidx = 0;
 
 #ifdef INET6
 	while (!LIST_EMPTY(&im6o->im6o_memberships)) {
@@ -1653,7 +1653,7 @@ carp_multicast_cleanup(struct carp_softc *sc)
 		LIST_REMOVE(imm, i6mm_chain);
 		in6_leavegroup(imm);
 	}
-	im6o->im6o_multicast_ifp = NULL;
+	im6o->im6o_ifidx = 0;
 #endif
 
 	/* And any other multicast memberships */
@@ -1930,7 +1930,7 @@ carp_join_multicast(struct carp_softc *sc)
 
 	imo->imo_membership[0] = imm;
 	imo->imo_num_memberships = 1;
-	imo->imo_multicast_ifp = &sc->sc_if;
+	imo->imo_ifidx = sc->sc_if.if_index;
 	imo->imo_multicast_ttl = CARP_DFLTTL;
 	imo->imo_multicast_loop = 0;
 	return (0);
@@ -2039,7 +2039,7 @@ carp_join_multicast6(struct carp_softc *sc)
 	}
 
 	/* apply v6 multicast membership */
-	im6o->im6o_multicast_ifp = &sc->sc_if;
+	im6o->im6o_ifidx = sc->sc_if.if_index;
 	if (imm)
 		LIST_INSERT_HEAD(&im6o->im6o_memberships, imm,
 		    i6mm_chain);
diff --git a/sys/netinet/ip_mroute.c b/sys/netinet/ip_mroute.c
index 3124e1e25cf..7370ffe58a6 100644
--- a/sys/netinet/ip_mroute.c
+++ b/sys/netinet/ip_mroute.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_mroute.c,v 1.72 2014/12/05 15:50:04 mpi Exp $	*/
+/*	$OpenBSD: ip_mroute.c,v 1.73 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$NetBSD: ip_mroute.c,v 1.85 2004/04/26 01:31:57 matt Exp $	*/
 
 /*
@@ -1653,7 +1653,7 @@ send_packet(struct vif *vifp, struct mbuf *m)
 		 */
 		struct ip_moptions imo;
 
-		imo.imo_multicast_ifp = vifp->v_ifp;
+		imo.imo_ifidx = vifp->v_ifp->if_index;
 		imo.imo_multicast_ttl = mtod(m, struct ip *)->ip_ttl - IPTTLDEC;
 		imo.imo_multicast_loop = 1;
 
diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c
index 9d7fa320ff0..bb0b01d4f32 100644
--- a/sys/netinet/ip_output.c
+++ b/sys/netinet/ip_output.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_output.c,v 1.274 2014/12/08 10:51:00 mpi Exp $	*/
+/*	$OpenBSD: ip_output.c,v 1.275 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$NetBSD: ip_output.c,v 1.28 1996/02/13 23:43:07 christos Exp $	*/
 
 /*
@@ -191,8 +191,7 @@ ip_output(struct mbuf *m0, struct mbuf *opt, struct route *ro, int flags,
 
 		if ((IN_MULTICAST(ip->ip_dst.s_addr) ||
 		    (ip->ip_dst.s_addr == INADDR_BROADCAST)) &&
-		    imo != NULL && imo->imo_multicast_ifp != NULL) {
-			ifp = imo->imo_multicast_ifp;
+		    imo != NULL && (ifp = if_get(imo->imo_ifidx)) != NULL) {
 			mtu = ifp->if_mtu;
 			IFP_TO_IA(ifp, ia);
 		} else {
@@ -342,8 +341,7 @@ reroute:
 
 		if ((IN_MULTICAST(ip->ip_dst.s_addr) ||
 		    (ip->ip_dst.s_addr == INADDR_BROADCAST)) &&
-		    imo != NULL && imo->imo_multicast_ifp != NULL) {
-			ifp = imo->imo_multicast_ifp;
+		    imo != NULL && (ifp = if_get(imo->imo_ifidx)) != NULL) {
 			mtu = ifp->if_mtu;
 			IFP_TO_IA(ifp, ia);
 		} else {
@@ -1679,7 +1677,7 @@ ip_setmoptions(int optname, struct ip_moptions **imop, struct mbuf *m,
 		    (sizeof(*immp) * IP_MIN_MEMBERSHIPS), M_IPMOPTS,
 		    M_WAITOK|M_ZERO);
 		*imop = imo;
-		imo->imo_multicast_ifp = NULL;
+		imo->imo_ifidx = 0;
 		imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
 		imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
 		imo->imo_num_memberships = 0;
@@ -1704,7 +1702,7 @@ ip_setmoptions(int optname, struct ip_moptions **imop, struct mbuf *m,
 		 * chosen every time a multicast packet is sent.
 		 */
 		if (addr.s_addr == INADDR_ANY) {
-			imo->imo_multicast_ifp = NULL;
+			imo->imo_ifidx = 0;
 			break;
 		}
 		/*
@@ -1723,7 +1721,7 @@ ip_setmoptions(int optname, struct ip_moptions **imop, struct mbuf *m,
 			error = EADDRNOTAVAIL;
 			break;
 		}
-		imo->imo_multicast_ifp = ifp;
+		imo->imo_ifidx = ifp->if_index;
 		break;
 
 	case IP_MULTICAST_TTL:
@@ -1923,7 +1921,7 @@ ip_setmoptions(int optname, struct ip_moptions **imop, struct mbuf *m,
 	/*
 	 * If all options have default values, no need to keep the data.
 	 */
-	if (imo->imo_multicast_ifp == NULL &&
+	if (imo->imo_ifidx == 0 &&
 	    imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL &&
 	    imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP &&
 	    imo->imo_num_memberships == 0) {
@@ -1945,6 +1943,7 @@ ip_getmoptions(int optname, struct ip_moptions *imo, struct mbuf **mp)
 	u_char *loop;
 	struct in_addr *addr;
 	struct in_ifaddr *ia;
+	struct ifnet *ifp;
 
 	*mp = m_get(M_WAIT, MT_SOOPTS);
 
@@ -1953,10 +1952,10 @@ ip_getmoptions(int optname, struct ip_moptions *imo, struct mbuf **mp)
 	case IP_MULTICAST_IF:
 		addr = mtod(*mp, struct in_addr *);
 		(*mp)->m_len = sizeof(struct in_addr);
-		if (imo == NULL || imo->imo_multicast_ifp == NULL)
+		if (imo == NULL || (ifp = if_get(imo->imo_ifidx)) == NULL)
 			addr->s_addr = INADDR_ANY;
 		else {
-			IFP_TO_IA(imo->imo_multicast_ifp, ia);
+			IFP_TO_IA(ifp, ia);
 			addr->s_addr = (ia == NULL) ? INADDR_ANY
 					: ia->ia_addr.sin_addr.s_addr;
 		}
diff --git a/sys/netinet/ip_var.h b/sys/netinet/ip_var.h
index c4abff43a44..c2dca5d0db3 100644
--- a/sys/netinet/ip_var.h
+++ b/sys/netinet/ip_var.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_var.h,v 1.57 2014/11/05 14:03:02 mpi Exp $	*/
+/*	$OpenBSD: ip_var.h,v 1.58 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$NetBSD: ip_var.h,v 1.16 1996/02/13 23:43:20 christos Exp $	*/
 
 /*
@@ -101,12 +101,12 @@ struct ipoption {
  * passed to ip_output when IP multicast options are in use.
  */
 struct ip_moptions {
-	struct	  ifnet *imo_multicast_ifp; /* ifp for outgoing multicasts */
+	struct in_multi **imo_membership; /* group memberships */
+	unsigned short imo_ifidx;	/* ifp index for outgoing multicasts */
 	u_int8_t  imo_multicast_ttl;	/* TTL for outgoing multicasts */
 	u_int8_t  imo_multicast_loop;	/* 1 => hear sends if a member */
 	u_int16_t imo_num_memberships;	/* no. memberships this socket */
 	u_int16_t imo_max_memberships;	/* max memberships this socket */
-	struct	  in_multi **imo_membership; /* group memberships */
 };
 
 #include <sys/queue.h>
diff --git a/sys/netinet6/in6_src.c b/sys/netinet6/in6_src.c
index f19dce62e86..aedab78a11f 100644
--- a/sys/netinet6/in6_src.c
+++ b/sys/netinet6/in6_src.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: in6_src.c,v 1.49 2014/12/05 15:50:04 mpi Exp $	*/
+/*	$OpenBSD: in6_src.c,v 1.50 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$KAME: in6_src.c,v 1.36 2001/02/06 04:08:17 itojun Exp $	*/
 
 /*
@@ -200,7 +200,7 @@ in6_selectsrc(struct in6_addr **in6src, struct sockaddr_in6 *dstsock,
 	 * choose a loopback interface as the outgoing interface.
 	 */
 	if (IN6_IS_ADDR_MULTICAST(dst)) {
-		ifp = mopts ? mopts->im6o_multicast_ifp : NULL;
+		ifp = mopts ? if_get(mopts->im6o_ifidx) : NULL;
 
 		if (!ifp && dstsock->sin6_scope_id)
 			ifp = if_get(htons(dstsock->sin6_scope_id));
@@ -345,7 +345,7 @@ selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts,
 	 * interface for the address is specified by the caller, use it.
 	 */
 	if (IN6_IS_ADDR_MULTICAST(dst) &&
-	    mopts != NULL && (ifp = mopts->im6o_multicast_ifp) != NULL) {
+	    mopts != NULL && (ifp = if_get(mopts->im6o_ifidx)) != NULL) {
 		goto done; /* we do not need a route for multicast. */
 	}
 
@@ -617,8 +617,7 @@ in6_embedscope(struct in6_addr *in6, const struct sockaddr_in6 *sin6,
 			in6->s6_addr16[1] = htons(pi->ipi6_ifindex);
 		} else if (in6p && IN6_IS_ADDR_MULTICAST(in6) &&
 			   in6p->inp_moptions6 &&
-			   in6p->inp_moptions6->im6o_multicast_ifp) {
-			ifp = in6p->inp_moptions6->im6o_multicast_ifp;
+			   (ifp = if_get(in6p->inp_moptions6->im6o_ifidx))) {
 			in6->s6_addr16[1] = htons(ifp->if_index);
 		} else if (scopeid) {
 			ifp = if_get(scopeid);
diff --git a/sys/netinet6/ip6_mroute.c b/sys/netinet6/ip6_mroute.c
index 7b33c20b650..0e62941c189 100644
--- a/sys/netinet6/ip6_mroute.c
+++ b/sys/netinet6/ip6_mroute.c
@@ -1437,7 +1437,7 @@ phyint_send(struct ip6_hdr *ip6, struct mif6 *mifp, struct mbuf *m)
 	if (m->m_pkthdr.rcvif == NULL) {
 		struct ip6_moptions im6o;
 
-		im6o.im6o_multicast_ifp = ifp;
+		im6o.im6o_ifidx = ifp->if_index;
 		/* XXX: ip6_output will override ip6->ip6_hlim */
 		im6o.im6o_multicast_hlim = ip6->ip6_hlim;
 		im6o.im6o_multicast_loop = 1;
diff --git a/sys/netinet6/ip6_output.c b/sys/netinet6/ip6_output.c
index 12aa01ebffe..4e052947b12 100644
--- a/sys/netinet6/ip6_output.c
+++ b/sys/netinet6/ip6_output.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip6_output.c,v 1.163 2014/12/05 15:50:04 mpi Exp $	*/
+/*	$OpenBSD: ip6_output.c,v 1.164 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$KAME: ip6_output.c,v 1.172 2001/03/25 09:55:56 itojun Exp $	*/
 
 /*
@@ -2329,7 +2329,7 @@ ip6_setmoptions(int optname, struct ip6_moptions **im6op, struct mbuf *m)
 		if (im6o == NULL)
 			return (ENOBUFS);
 		*im6op = im6o;
-		im6o->im6o_multicast_ifp = NULL;
+		im6o->im6o_ifidx = 0;
 		im6o->im6o_multicast_hlim = ip6_defmcasthlim;
 		im6o->im6o_multicast_loop = IPV6_DEFAULT_MULTICAST_LOOP;
 		LIST_INIT(&im6o->im6o_memberships);
@@ -2359,7 +2359,7 @@ ip6_setmoptions(int optname, struct ip6_moptions **im6op, struct mbuf *m)
 				break;
 			}
 		}
-		im6o->im6o_multicast_ifp = ifp;
+		im6o->im6o_ifidx = ifindex;
 		break;
 
 	case IPV6_MULTICAST_HOPS:
@@ -2572,7 +2572,7 @@ ip6_setmoptions(int optname, struct ip6_moptions **im6op, struct mbuf *m)
 	 * If all options have default values, no need to keep the option
 	 * structure.
 	 */
-	if (im6o->im6o_multicast_ifp == NULL &&
+	if (im6o->im6o_ifidx == 0 &&
 	    im6o->im6o_multicast_hlim == ip6_defmcasthlim &&
 	    im6o->im6o_multicast_loop == IPV6_DEFAULT_MULTICAST_LOOP &&
 	    LIST_EMPTY(&im6o->im6o_memberships)) {
@@ -2598,10 +2598,10 @@ ip6_getmoptions(int optname, struct ip6_moptions *im6o, struct mbuf **mp)
 	case IPV6_MULTICAST_IF:
 		ifindex = mtod(*mp, u_int *);
 		(*mp)->m_len = sizeof(u_int);
-		if (im6o == NULL || im6o->im6o_multicast_ifp == NULL)
+		if (im6o == NULL || im6o->im6o_ifidx == 0)
 			*ifindex = 0;
 		else
-			*ifindex = im6o->im6o_multicast_ifp->if_index;
+			*ifindex = im6o->im6o_ifidx;
 		return (0);
 
 	case IPV6_MULTICAST_HOPS:
diff --git a/sys/netinet6/ip6_var.h b/sys/netinet6/ip6_var.h
index fcbedc4af0d..371da75783b 100644
--- a/sys/netinet6/ip6_var.h
+++ b/sys/netinet6/ip6_var.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip6_var.h,v 1.49 2014/07/11 16:39:06 henning Exp $	*/
+/*	$OpenBSD: ip6_var.h,v 1.50 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$KAME: ip6_var.h,v 1.33 2000/06/11 14:59:20 jinmei Exp $	*/
 
 /*
@@ -92,10 +92,10 @@ struct	ip6asfrag {
 #define IP6_REASS_MBUF(ip6af) ((ip6af)->ip6af_m)
 
 struct	ip6_moptions {
-	struct	ifnet *im6o_multicast_ifp; /* ifp for outgoing multicasts */
+	LIST_HEAD(, in6_multi_mship) im6o_memberships;
+	unsigned short im6o_ifidx;	/* ifp index for outgoing multicasts */
 	u_char	im6o_multicast_hlim;	/* hoplimit for outgoing multicasts */
 	u_char	im6o_multicast_loop;	/* 1 >= hear sends if a member */
-	LIST_HEAD(, in6_multi_mship) im6o_memberships;
 };
 
 /*
diff --git a/sys/netinet6/mld6.c b/sys/netinet6/mld6.c
index 1e0cc208b34..8364d591c38 100644
--- a/sys/netinet6/mld6.c
+++ b/sys/netinet6/mld6.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mld6.c,v 1.39 2014/11/18 02:37:31 tedu Exp $	*/
+/*	$OpenBSD: mld6.c,v 1.40 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$KAME: mld6.c,v 1.26 2001/02/16 14:50:35 itojun Exp $	*/
 
 /*
@@ -438,7 +438,7 @@ mld6_sendpkt(struct in6_multi *in6m, int type, const struct in6_addr *dst)
 
 	/* construct multicast option */
 	bzero(&im6o, sizeof(im6o));
-	im6o.im6o_multicast_ifp = ifp;
+	im6o.im6o_ifidx = ifp->if_index;
 	im6o.im6o_multicast_hlim = 1;
 
 	/*
diff --git a/sys/netinet6/nd6_nbr.c b/sys/netinet6/nd6_nbr.c
index b08a9368aed..c3c488aa441 100644
--- a/sys/netinet6/nd6_nbr.c
+++ b/sys/netinet6/nd6_nbr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: nd6_nbr.c,v 1.86 2014/12/05 15:50:04 mpi Exp $	*/
+/*	$OpenBSD: nd6_nbr.c,v 1.87 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$KAME: nd6_nbr.c,v 1.61 2001/02/10 16:06:14 jinmei Exp $	*/
 
 /*
@@ -398,7 +398,7 @@ nd6_ns_output(struct ifnet *ifp, struct in6_addr *daddr6,
 
 	if (daddr6 == NULL || IN6_IS_ADDR_MULTICAST(daddr6)) {
 		m->m_flags |= M_MCAST;
-		im6o.im6o_multicast_ifp = ifp;
+		im6o.im6o_ifidx = ifp->if_index;
 		im6o.im6o_multicast_hlim = 255;
 		im6o.im6o_multicast_loop = 0;
 	}
@@ -949,7 +949,7 @@ nd6_na_output(struct ifnet *ifp, struct in6_addr *daddr6,
 
 	if (IN6_IS_ADDR_MULTICAST(daddr6)) {
 		m->m_flags |= M_MCAST;
-		im6o.im6o_multicast_ifp = ifp;
+		im6o.im6o_ifidx = ifp->if_index;
 		im6o.im6o_multicast_hlim = 255;
 		im6o.im6o_multicast_loop = 0;
 	}
diff --git a/sys/netinet6/nd6_rtr.c b/sys/netinet6/nd6_rtr.c
index 0d24392c5e9..b5656990849 100644
--- a/sys/netinet6/nd6_rtr.c
+++ b/sys/netinet6/nd6_rtr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: nd6_rtr.c,v 1.92 2014/12/05 15:50:04 mpi Exp $	*/
+/*	$OpenBSD: nd6_rtr.c,v 1.93 2014/12/17 09:45:59 mpi Exp $	*/
 /*	$KAME: nd6_rtr.c,v 1.97 2001/02/07 11:09:13 itojun Exp $	*/
 
 /*
@@ -202,7 +202,7 @@ nd6_rs_output(struct ifnet* ifp, struct in6_ifaddr *ia6)
 	m->m_flags |= M_MCAST;
 	m->m_pkthdr.csum_flags |= M_ICMP_CSUM_OUT;
 
-	im6o.im6o_multicast_ifp = ifp;
+	im6o.im6o_ifidx = ifp->if_index;
 	im6o.im6o_multicast_hlim = 255;
 	im6o.im6o_multicast_loop = 0;