Index: pf.c
===================================================================
RCS file: /cvs/src/sys/net/pf.c,v
retrieving revision 1.1107
diff -u -p -r1.1107 pf.c
--- pf.c	3 Feb 2021 07:41:12 -0000	1.1107
+++ pf.c	4 Feb 2021 22:43:11 -0000
@@ -6015,7 +6015,7 @@ pf_route(struct pf_pdesc *pd, struct pf_
 	rtableid = m0->m_pkthdr.ph_rtableid;
 
 	rt = rtalloc(sintosa(dst), RT_RESOLVE, rtableid);
-	if (!rtisvalid(rt)) {
+	if (!rtisvalid(rt) || ISSET(rt->rt_flags, RTF_LOCAL)) {
 		if (s->rt != PF_DUPTO) {
 			pf_send_icmp(m0, ICMP_UNREACH, ICMP_UNREACH_HOST,
 			    0, pd->af, s->rule.ptr, pd->rdomain);
@@ -6025,7 +6025,7 @@ pf_route(struct pf_pdesc *pd, struct pf_
 	}
 
 	ifp = if_get(rt->rt_ifidx);
-	if (ifp == NULL)
+	if (ifp == NULL || ISSET(ifp->if_flags, IFF_LOOPBACK))
 		goto bad;
 
 	/* A locally generated packet may have invalid source address. */
@@ -6159,7 +6159,7 @@ pf_route6(struct pf_pdesc *pd, struct pf
 	if (IN6_IS_SCOPE_EMBED(&dst->sin6_addr))
 		dst->sin6_addr.s6_addr16[1] = htons(ifp->if_index);
 	rt = rtalloc(sin6tosa(dst), RT_RESOLVE, rtableid);
-	if (!rtisvalid(rt)) {
+	if (!rtisvalid(rt) || ISSET(rt->rt_flags, RTF_LOCAL)) {
 		if (s->rt != PF_DUPTO) {
 			pf_send_icmp(m0, ICMP6_DST_UNREACH,
 			    ICMP6_DST_UNREACH_NOROUTE, 0,
@@ -6170,7 +6170,7 @@ pf_route6(struct pf_pdesc *pd, struct pf
 	}
 
 	ifp = if_get(rt->rt_ifidx);
-	if (ifp == NULL)
+	if (ifp == NULL || ISSET(ifp->if_flags, IFF_LOOPBACK))
 		goto bad;
 
 	/* A locally generated packet may have invalid source address. */