Index: sys/netinet/in_pcb.h
===================================================================
--- sys/netinet/in_pcb.h
+++ sys/netinet/in_pcb.h
@@ -687,8 +687,8 @@
 void	in_pcbpurgeif0(struct inpcbinfo *, struct ifnet *);
 int	in_pcballoc(struct socket *, struct inpcbinfo *);
 int	in_pcbbind(struct inpcb *, struct sockaddr *, struct ucred *);
-int	in_pcb_lport(struct inpcb *, struct in_addr *, u_short *,
-	    struct ucred *, int);
+int	in_pcb_lport(struct inpcb *, struct sockaddr *, struct in_addr *,
+	    u_short *, struct ucred *, int);
 int	in_pcbbind_setup(struct inpcb *, struct sockaddr *, in_addr_t *,
 	    u_short *, struct ucred *);
 int	in_pcbconnect(struct inpcb *, struct sockaddr *, struct ucred *);
Index: sys/netinet/in_pcb.c
===================================================================
--- sys/netinet/in_pcb.c
+++ sys/netinet/in_pcb.c
@@ -372,8 +372,8 @@
  */
 #if defined(INET) || defined(INET6)
 int
-in_pcb_lport(struct inpcb *inp, struct in_addr *laddrp, u_short *lportp,
-    struct ucred *cred, int lookupflags)
+in_pcb_lport(struct inpcb *inp, struct sockaddr *nam, struct in_addr *laddrp,
+    u_short *lportp, struct ucred *cred, int lookupflags)
 {
 	struct inpcbinfo *pcbinfo;
 	struct inpcb *tmpinp;
@@ -382,6 +382,7 @@
 	u_short aux, first, last, lport;
 #ifdef INET
 	struct in_addr laddr;
+	struct sockaddr_in *sin = NULL;
 #endif
 
 	pcbinfo = inp->inp_pcbinfo;
@@ -448,6 +449,7 @@
 		KASSERT(laddrp != NULL, ("%s: laddrp NULL for v4 inp %p",
 		    __func__, inp));
 		laddr = *laddrp;
+		sin = (struct sockaddr_in *)nam;
 	}
 #endif
 	tmpinp = NULL;	/* Make compiler happy. */
@@ -467,16 +469,29 @@
 		lport = htons(*lastport);
 
 #ifdef INET6
-		if ((inp->inp_vflag & INP_IPV6) != 0)
-			tmpinp = in6_pcblookup_local(pcbinfo,
-			    &inp->in6p_laddr, lport, lookupflags, cred);
+		if ((inp->inp_vflag & INP_IPV6) != 0) {
+			struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
+			if (sin6 != NULL && (inp->inp_flags & INP_ANONPORT)) {
+				tmpinp = in6_pcblookup_hash_locked(pcbinfo,
+				    &sin6->sin6_addr, sin6->sin6_port,
+				    &inp->in6p_laddr, lport,
+				    lookupflags & (~INPLOOKUP_WILDCARD),
+				    NULL);
+			} else
+				tmpinp = in6_pcblookup_local(pcbinfo,
+				    &inp->in6p_laddr, lport, lookupflags, cred);
+		}
 #endif
 #if defined(INET) && defined(INET6)
 		else
 #endif
 #ifdef INET
-			tmpinp = in_pcblookup_local(pcbinfo, laddr,
-			    lport, lookupflags, cred);
+			if (sin != NULL && (inp->inp_flags & INP_ANONPORT))
+				tmpinp = in_pcblookup_hash_locked(pcbinfo, sin->sin_addr, sin->sin_port, laddr,
+				    lport, lookupflags & (~INPLOOKUP_WILDCARD), NULL);
+			else
+				tmpinp = in_pcblookup_local(pcbinfo, laddr,
+				    lport, lookupflags, cred);
 #endif
 	} while (tmpinp != NULL);
 
@@ -572,7 +587,7 @@
 		return (EINVAL);
 	if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0)
 		lookupflags = INPLOOKUP_WILDCARD;
-	if (nam == NULL) {
+	if (nam == NULL || ((*lportp) == 0 && (inp->inp_flags & INP_ANONPORT))) {
 		if ((error = prison_local_ip4(cred, &laddr)) != 0)
 			return (error);
 	} else {
@@ -693,7 +708,7 @@
 	if (*lportp != 0)
 		lport = *lportp;
 	if (lport == 0) {
-		error = in_pcb_lport(inp, &laddr, &lport, cred, lookupflags);
+		error = in_pcb_lport(inp, nam, &laddr, &lport, cred, lookupflags);
 		if (error != 0)
 			return (error);
 
Index: sys/netinet/tcp_usrreq.c
===================================================================
--- sys/netinet/tcp_usrreq.c
+++ sys/netinet/tcp_usrreq.c
@@ -1217,9 +1217,12 @@
 	INP_HASH_WLOCK(&V_tcbinfo);
 
 	if (inp->inp_lport == 0) {
-		error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
-		if (error)
+		inp->inp_flags |= INP_ANONPORT;
+		error = in_pcbbind(inp, nam, td->td_ucred);
+		if (error) {
+			inp->inp_flags &= ~INP_ANONPORT;
 			goto out;
+		}
 	}
 
 	/*
@@ -1275,9 +1278,12 @@
 	INP_HASH_WLOCK(&V_tcbinfo);
 
 	if (inp->inp_lport == 0) {
-		error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
-		if (error)
+		inp->inp_flags |= INP_ANONPORT;
+		error = in6_pcbbind(inp, nam, td->td_ucred);
+		if (error) {
+			inp->inp_flags &= ~INP_ANONPORT;
 			goto out;
+		}
 	}
 	error = in6_pcbconnect(inp, nam, td->td_ucred);
 	if (error != 0)
Index: sys/netinet6/in6_pcb.h
===================================================================
--- sys/netinet6/in6_pcb.h
+++ sys/netinet6/in6_pcb.h
@@ -112,7 +112,8 @@
 int	in6_mapped_sockaddr(struct socket *so, struct sockaddr **nam);
 int	in6_mapped_peeraddr(struct socket *so, struct sockaddr **nam);
 int	in6_selecthlim(struct in6pcb *, struct ifnet *);
-int	in6_pcbsetport(struct in6_addr *, struct inpcb *, struct ucred *);
+int	in6_pcbsetport(struct sockaddr *, struct in6_addr *, struct inpcb *,
+			    struct ucred *);
 void	init_sin6(struct sockaddr_in6 *sin6, struct mbuf *m);
 #endif /* _KERNEL */
 
Index: sys/netinet6/in6_pcb.c
===================================================================
--- sys/netinet6/in6_pcb.c
+++ sys/netinet6/in6_pcb.c
@@ -131,7 +131,7 @@
 		return (EINVAL);
 	if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0)
 		lookupflags = INPLOOKUP_WILDCARD;
-	if (nam == NULL) {
+	if (nam == NULL || (inp->inp_flags & INP_ANONPORT)) {
 		if ((error = prison_local_ip6(cred, &inp->in6p_laddr,
 		    ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0))) != 0)
 			return (error);
@@ -295,7 +295,7 @@
 		inp->in6p_laddr = sin6->sin6_addr;
 	}
 	if (lport == 0) {
-		if ((error = in6_pcbsetport(&inp->in6p_laddr, inp, cred)) != 0) {
+		if ((error = in6_pcbsetport(nam, &inp->in6p_laddr, inp, cred)) != 0) {
 			/* Undo an address bind that may have occurred. */
 			inp->in6p_laddr = in6addr_any;
 			return (error);
@@ -415,9 +415,12 @@
 	}
 	if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
 		if (inp->inp_lport == 0) {
-			error = in6_pcbbind(inp, (struct sockaddr *)0, cred);
-			if (error)
+			inp->inp_flags |= INP_ANONPORT;
+			error = in6_pcbbind(inp, nam, cred);
+			if (error) {
+				inp->inp_flags &= ~INP_ANONPORT;
 				return (error);
+			}
 		}
 		inp->in6p_laddr = addr6;
 	}
Index: sys/netinet6/in6_src.c
===================================================================
--- sys/netinet6/in6_src.c
+++ sys/netinet6/in6_src.c
@@ -956,7 +956,8 @@
  * share this function by all *bsd*...
  */
 int
-in6_pcbsetport(struct in6_addr *laddr, struct inpcb *inp, struct ucred *cred)
+in6_pcbsetport(struct sockaddr *nam6, struct in6_addr *laddr, struct inpcb *inp,
+    struct ucred *cred)
 {
 	struct socket *so = inp->inp_socket;
 	u_int16_t lport = 0;
@@ -979,7 +980,7 @@
 
 	inp->inp_flags |= INP_ANONPORT;
 
-	error = in_pcb_lport(inp, NULL, &lport, cred, lookupflags);
+	error = in_pcb_lport(inp, nam6, NULL, &lport, cred, lookupflags);
 	if (error != 0)
 		return (error);
 
Index: sys/netinet6/udp6_usrreq.c
===================================================================
--- sys/netinet6/udp6_usrreq.c
+++ sys/netinet6/udp6_usrreq.c
@@ -742,11 +742,16 @@
 				error = EADDRNOTAVAIL;
 			goto release;
 		}
-		if (inp->inp_lport == 0 &&
-		    (error = in6_pcbsetport(laddr, inp, td->td_ucred)) != 0) {
-			/* Undo an address bind that may have occurred. */
-			inp->in6p_laddr = in6addr_any;
-			goto release;
+		if (inp->inp_lport == 0) {
+			inp->inp_flags |= INP_ANONPORT;
+			error = in6_pcbsetport((struct sockaddr *)addr6, laddr,
+						inp, td->td_ucred);
+			if (error) {
+				inp->inp_flags &= ~INP_ANONPORT;
+				/* Undo an address bind that may have occurred. */
+				inp->in6p_laddr = in6addr_any;
+				goto release;
+			}
 		}
 	} else {
 		if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {