Add m_clrprotoflags() to clear protocol specific mbuf flags at up and

downwards layer crossings.

Consistently use it within IP, IPv6 and ethernet protocols.

Discussed with:	trociny, glebius

4 files changed, 5 insertions, 3 deletions

diff --git a/sys/netinet6/ip6_mroute.c b/sys/netinet6/ip6_mroute.c
index 194aaf5..40c8c44 100644
--- a/sys/netinet6/ip6_mroute.c
+++ b/sys/netinet6/ip6_mroute.c
@@ -1648,6 +1648,7 @@ phyint_send(struct ip6_hdr *ip6, struct mif6 *mifp, struct mbuf *m)
 		 * We just call if_output instead of nd6_output here, since
 		 * we need no ND for a multicast forwarded packet...right?
 		 */
+		m_clrprotoflags(m);	/* Avoid confusing lower layers. */
 		error = (*ifp->if_output)(ifp, mb_copy,
 		    (struct sockaddr *)&dst6, NULL);
 #ifdef MRT6DEBUG
diff --git a/sys/netinet6/mld6.c b/sys/netinet6/mld6.c
index 560e8d6..683a0d5 100644
--- a/sys/netinet6/mld6.c
+++ b/sys/netinet6/mld6.c
@@ -3098,7 +3098,7 @@ mld_dispatch_packet(struct mbuf *m)
 	}
 
 	mld_scrub_context(m0);
-	m->m_flags &= ~(M_PROTOFLAGS);
+	m_clrprotoflags(m);
 	m0->m_pkthdr.rcvif = V_loif;
 
 	ip6 = mtod(m0, struct ip6_hdr *);
diff --git a/sys/netinet6/nd6.c b/sys/netinet6/nd6.c
index 7dcf2e1..7755da1 100644
--- a/sys/netinet6/nd6.c
+++ b/sys/netinet6/nd6.c
@@ -2082,8 +2082,7 @@ nd6_output_lle(struct ifnet *ifp, struct ifnet *origifp, struct mbuf *m0,
 		}
 		return (error);
 	}
-	/* Reset layer specific mbuf flags to avoid confusing lower layers. */
-	m->m_flags &= ~(M_PROTOFLAGS);  
+	m_clrprotoflags(m);	/* Avoid confusing lower layers. */
 	if ((ifp->if_flags & IFF_LOOPBACK) != 0) {
 		return ((*ifp->if_output)(origifp, m, (struct sockaddr *)dst,
 		    NULL));
diff --git a/sys/netinet6/send.c b/sys/netinet6/send.c
index 5624366..233abdb 100644
--- a/sys/netinet6/send.c
+++ b/sys/netinet6/send.c
@@ -180,6 +180,8 @@ send_output(struct mbuf *m, struct ifnet *ifp, int direction)
 		dst.sin6_len = sizeof(dst);
 		dst.sin6_addr = ip6->ip6_dst;
 
+		m_clrprotoflags(m);	/* Avoid confusing lower layers. */
+
 		/*
 		 * Output the packet as nd6.c:nd6_output_lle() would do.
 		 * The mbuf is always consumed, so we do not have to care