From: bluhm <bluhm@openbsd.org>
Date: Fri, 22 Apr 2022 12:10:57 +0000 (+0000)
Subject: ARP, ND6 and PPPoE are not MP safe.  Protect them with kernel lock
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=a4551fe8d769711606b758f980be5edf29edccd1;p=openbsd

ARP, ND6 and PPPoE are not MP safe.  Protect them with kernel lock
for now.  Then IP forward can run in parallel and this can be fixed
later.
OK sashan@
---

diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index c154241e91f..45dbd6c4d2d 100644
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ethersubr.c,v 1.278 2022/02/22 01:15:02 guenther Exp $	*/
+/*	$OpenBSD: if_ethersubr.c,v 1.279 2022/04/22 12:10:57 bluhm Exp $	*/
 /*	$NetBSD: if_ethersubr.c,v 1.19 1996/05/07 02:40:30 thorpej Exp $	*/
 
 /*
@@ -221,7 +221,10 @@ ether_resolve(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 
 	switch (af) {
 	case AF_INET:
+		KERNEL_LOCK();
+		/* XXXSMP there is a MP race in arpresolve() */
 		error = arpresolve(ifp, rt, m, dst, eh->ether_dhost);
+		KERNEL_UNLOCK();
 		if (error)
 			return (error);
 		eh->ether_type = htons(ETHERTYPE_IP);
@@ -244,7 +247,10 @@ ether_resolve(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 		break;
 #ifdef INET6
 	case AF_INET6:
+		KERNEL_LOCK();
+		/* XXXSMP there is a MP race in nd6_resolve() */
 		error = nd6_resolve(ifp, rt, m, dst, eh->ether_dhost);
+		KERNEL_UNLOCK();
 		if (error)
 			return (error);
 		eh->ether_type = htons(ETHERTYPE_IPV6);
@@ -270,13 +276,19 @@ ether_resolve(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 			break;
 #ifdef INET6
 		case AF_INET6:
+			KERNEL_LOCK();
+			/* XXXSMP there is a MP race in nd6_resolve() */
 			error = nd6_resolve(ifp, rt, m, dst, eh->ether_dhost);
+			KERNEL_UNLOCK();
 			if (error)
 				return (error);
 			break;
 #endif
 		case AF_INET:
+			KERNEL_LOCK();
+			/* XXXSMP there is a MP race in arpresolve() */
 			error = arpresolve(ifp, rt, m, dst, eh->ether_dhost);
+			KERNEL_UNLOCK();
 			if (error)
 				return (error);
 			break;
@@ -528,12 +540,14 @@ ether_input(struct ifnet *ifp, struct mbuf *m)
 	case ETHERTYPE_PPPOE:
 		if (m->m_flags & (M_MCAST | M_BCAST))
 			goto dropanyway;
+		KERNEL_LOCK();
 #ifdef PIPEX
 		if (pipex_enable) {
 			struct pipex_session *session;
 
 			if ((session = pipex_pppoe_lookup_session(m)) != NULL) {
 				pipex_pppoe_input(m, session);
+				KERNEL_UNLOCK();
 				return;
 			}
 		}
@@ -542,6 +556,7 @@ ether_input(struct ifnet *ifp, struct mbuf *m)
 			pppoe_disc_input(m);
 		else
 			pppoe_data_input(m);
+		KERNEL_UNLOCK();
 		return;
 #endif
 #ifdef MPLS