From 7a3dea7e8ef7831bf445b52ab2c5981784d9068e Mon Sep 17 00:00:00 2001
From: bluhm <bluhm@openbsd.org>
Date: Mon, 19 Jun 2017 17:00:16 +0000
Subject: [PATCH] The IP multicast forward functions return an errno, call the
 variable error.  Make the ip_mforward() return value consistent.  Simplify
 the caller logic in ipv6_input() like in IPv4. OK mpi@

---
 sys/netinet/ip_input.c   |  8 ++++----
 sys/netinet/ip_mroute.c  |  5 ++---
 sys/netinet6/ip6_input.c | 22 ++++++++++++++--------
 3 files changed, 20 insertions(+), 15 deletions(-)

diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index 9c8c9ba0280..c4bbed9d015 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_input.c,v 1.310 2017/05/31 05:59:09 mpi Exp $	*/
+/*	$OpenBSD: ip_input.c,v 1.311 2017/06/19 17:00:16 bluhm Exp $	*/
 /*	$NetBSD: ip_input.c,v 1.30 1996/03/16 23:53:58 christos Exp $	*/
 
 /*
@@ -377,7 +377,7 @@ ipv4_input(struct ifnet *ifp, struct mbuf *m)
 
 #ifdef MROUTING
 		if (ipmforwarding && ip_mrouter[ifp->if_rdomain]) {
-			int rv;
+			int error;
 
 			if (m->m_flags & M_EXT) {
 				if ((m = m_pullup(m, hlen)) == NULL) {
@@ -399,9 +399,9 @@ ipv4_input(struct ifnet *ifp, struct mbuf *m)
 			 * ip_output().)
 			 */
 			KERNEL_LOCK();
-			rv = ip_mforward(m, ifp);
+			error = ip_mforward(m, ifp);
 			KERNEL_UNLOCK();
-			if (rv != 0) {
+			if (error) {
 				ipstat_inc(ips_cantforward);
 				goto bad;
 			}
diff --git a/sys/netinet/ip_mroute.c b/sys/netinet/ip_mroute.c
index 0c32da6c4e4..1f4e6da4478 100644
--- a/sys/netinet/ip_mroute.c
+++ b/sys/netinet/ip_mroute.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip_mroute.c,v 1.118 2017/05/16 13:09:21 rzalamena Exp $	*/
+/*	$OpenBSD: ip_mroute.c,v 1.119 2017/06/19 17:00:16 bluhm Exp $	*/
 /*	$NetBSD: ip_mroute.c,v 1.85 2004/04/26 01:31:57 matt Exp $	*/
 
 /*
@@ -1084,8 +1084,7 @@ ip_mforward(struct mbuf *m, struct ifnet *ifp)
 		if ((srctun++ % 1000) == 0)
 			log(LOG_ERR, "ip_mforward: received source-routed "
 			    "packet from %x\n", ntohl(ip->ip_src.s_addr));
-
-		return (1);
+		return (EOPNOTSUPP);
 	}
 
 	/*
diff --git a/sys/netinet6/ip6_input.c b/sys/netinet6/ip6_input.c
index 7018444ba98..b763c59e562 100644
--- a/sys/netinet6/ip6_input.c
+++ b/sys/netinet6/ip6_input.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ip6_input.c,v 1.194 2017/05/31 05:59:09 mpi Exp $	*/
+/*	$OpenBSD: ip6_input.c,v 1.195 2017/06/19 17:00:16 bluhm Exp $	*/
 /*	$KAME: ip6_input.c,v 1.188 2001/03/29 05:34:31 itojun Exp $	*/
 
 /*
@@ -381,6 +381,8 @@ ipv6_input(struct ifnet *ifp, struct mbuf *m)
 
 #ifdef MROUTING
 		if (ip6_mforwarding && ip6_mrouter[ifp->if_rdomain]) {
+			int error;
+
 			if (ip6_hbhchcheck(m, &off, &nxt, &ours))
 				goto out;
 
@@ -395,16 +397,20 @@ ipv6_input(struct ifnet *ifp, struct mbuf *m)
 			 * must be discarded, else it may be accepted below.
 			 */
 			KERNEL_LOCK();
-			if (ip6_mforward(ip6, ifp, m)) {
+			error = ip6_mforward(ip6, ifp, m);
+			KERNEL_UNLOCK();
+			if (error) {
 				ip6stat_inc(ip6s_cantforward);
-				m_freem(m);
-			} else if (ours) {
+				goto bad;
+			}
+
+			if (ours) {
+				KERNEL_LOCK();
 				ip6_deliver(&m, &off, nxt, AF_INET6);
-			} else {
-				m_freem(m);
+				KERNEL_UNLOCK();
+				goto out;
 			}
-			KERNEL_UNLOCK();
-			goto out;
+			goto bad;
 		}
 #endif
 		if (!ours) {
-- 
2.20.1