Index: rtsock.c
===================================================================
RCS file: /cvs/src/sys/net/rtsock.c,v
retrieving revision 1.259
diff -u -p -r1.259 rtsock.c
--- rtsock.c	18 Dec 2017 09:40:17 -0000	1.259
+++ rtsock.c	10 Feb 2018 02:00:53 -0000
@@ -138,6 +138,7 @@ struct routecb {
 	unsigned int		msgfilter;
 	unsigned int		flags;
 	u_int			rtableid;
+	int			seq;
 };
 #define	sotoroutecb(so)	((struct routecb *)(so)->so_pcb)
 
@@ -348,28 +349,32 @@ route_ctloutput(int op, struct socket *s
 void
 route_senddesync(void *data)
 {
-	struct rawcb	*rp;
-	struct routecb	*rop;
+	struct routecb	*rop = data;
 	struct mbuf	*desync_mbuf;
-
-	rp = (struct rawcb *)data;
-	rop = (struct routecb *)rp;
+	int		 seq;
 
 	/* If we are in a DESYNC state, try to send a RTM_DESYNC packet */
 	if ((rop->flags & ROUTECB_FLAG_DESYNC) == 0)
 		return;
 
+
 	/*
 	 * If we fail to alloc memory or if sbappendaddr()
 	 * fails, re-add timeout and try again.
 	 */
+	seq = rop->seq++;
 	desync_mbuf = rtm_msg1(RTM_DESYNC, NULL);
 	if (desync_mbuf != NULL) {
-		struct socket *so = rp->rcb_socket;
+		struct socket *so = rop->rcb.rcb_socket;
+		struct rt_msghdr *rtm;
+
+		rtm = mtod(desync_mbuf, struct rt_msghdr *);
+		rtm->rtm_seq = seq;
+
 		if (sbappendaddr(so, &so->so_rcv, &route_src,
 		    desync_mbuf, NULL) != 0) {
 			rop->flags &= ~ROUTECB_FLAG_DESYNC;
-			sorwakeup(rp->rcb_socket);
+			sorwakeup(so);
 			return;
 		}
 		m_freem(desync_mbuf);
@@ -379,13 +384,61 @@ route_senddesync(void *data)
 }
 
 void
+route_send(struct mbuf *m, struct socket *so, struct sockaddr *sosrc, int dup)
+{
+	struct routecb *rop = sotoroutecb(so);
+	struct rt_msghdr *rtm;
+	int seq;
+
+	seq = rop->seq++;
+
+	if (sbspace(so, &so->so_rcv) < m->m_pkthdr.len)
+		goto desync;
+
+	if (dup) {
+		m = m_dup_pkt(m, 0, M_NOWAIT);
+		if (m == NULL)
+			goto desync;
+	}
+
+	rtm = mtod(m, struct rt_msghdr *);
+
+        switch (rtm->rtm_type) { /* XXX check rtm_hdrlen ? */
+	case RTM_DELADDR:
+	case RTM_NEWADDR:
+        case RTM_IFINFO:
+        case RTM_IFANNOUNCE:
+#ifdef BFD
+        case RTM_BFD:
+#endif
+		break;
+        default:
+		rtm->rtm_seq = seq;
+                break;
+        }
+
+	if (sbappendaddr(so, &so->so_rcv, sosrc, m, NULL) == 0) {
+		m_freem(m);
+		goto desync;
+	}
+
+	sorwakeup(so);
+
+	return;
+
+desync:
+	/* Flag socket as desync'ed and flush required */
+	rop->flags |= ROUTECB_FLAG_DESYNC | ROUTECB_FLAG_FLUSH;
+	route_senddesync(rop);
+}
+
+void
 route_input(struct mbuf *m0, struct socket *so, sa_family_t sa_family)
 {
 	struct rawcb *rp;
 	struct routecb *rop;
 	struct rt_msghdr *rtm;
 	struct mbuf *m = m0;
-	int sockets = 0;
 	struct socket *last = NULL;
 	struct sockaddr *sosrc, *sodst;
 
@@ -455,43 +508,14 @@ route_input(struct mbuf *m0, struct sock
 		if ((rop->flags & ROUTECB_FLAG_FLUSH) != 0)
 			continue;
 
-		if (last) {
-			struct mbuf *n;
-			if ((n = m_copym(m, 0, M_COPYALL, M_NOWAIT)) != NULL) {
-				if (sbspace(last, &last->so_rcv) < (2*MSIZE) ||
-				    sbappendaddr(last, &last->so_rcv, sosrc,
-				    n, (struct mbuf *)NULL) == 0) {
-					/*
-					 * Flag socket as desync'ed and
-					 * flush required
-					 */
-					sotoroutecb(last)->flags |=
-					    ROUTECB_FLAG_DESYNC |
-					    ROUTECB_FLAG_FLUSH;
-					route_senddesync(sotorawcb(last));
-					m_freem(n);
-				} else {
-					sorwakeup(last);
-					sockets++;
-				}
-			}
-		}
+		if (last)
+			route_send(m, last, sosrc, 1);
+
 		last = rp->rcb_socket;
 	}
-	if (last) {
-		if (sbspace(last, &last->so_rcv) < (2 * MSIZE) ||
-		    sbappendaddr(last, &last->so_rcv, sosrc,
-		    m, (struct mbuf *)NULL) == 0) {
-			/* Flag socket as desync'ed and flush required */
-			sotoroutecb(last)->flags |=
-			    ROUTECB_FLAG_DESYNC | ROUTECB_FLAG_FLUSH;
-			route_senddesync(sotorawcb(last));
-			m_freem(m);
-		} else {
-			sorwakeup(last);
-			sockets++;
-		}
-	} else
+	if (last)
+		route_send(m, last, sosrc, 0);
+	else
 		m_freem(m);
 }