Index: ip_carp.c
===================================================================
RCS file: /cvs/src/sys/netinet/ip_carp.c,v
retrieving revision 1.338
diff -u -p -r1.338 ip_carp.c
--- ip_carp.c	10 Jun 2019 16:32:51 -0000	1.338
+++ ip_carp.c	4 Nov 2019 11:44:16 -0000
@@ -950,10 +950,9 @@ carpdetach(void *arg)
 	if_ih_remove(ifp0, carp_input, NULL);
 
 	SRPL_REMOVE_LOCKED(&carp_sc_rc, cif, sc, carp_softc, sc_list);
-	if (SRPL_EMPTY_LOCKED(cif))
-		ifpromisc(ifp0, 0);
 	sc->sc_carpdev = NULL;
 
+	ifpromisc(ifp0, 0);
 	hook_disestablish(ifp0->if_linkstatehooks, sc->lh_cookie);
 	hook_disestablish(ifp0->if_detachhooks, sc->dh_cookie);
 }
@@ -1685,6 +1684,10 @@ carp_set_ifp(struct carp_softc *sc, stru
 	if (ifp0->if_type != IFT_ETHER)
 		return (EINVAL);
 
+	cif = &ifp0->if_carp;
+	if (carp_check_dup_vhids(sc, cif, NULL))
+		return (EINVAL);
+
 	sc->dh_cookie = hook_establish(ifp0->if_detachhooks, 0,
             carpdetach, sc);
 	if (sc->dh_cookie == NULL)
@@ -1697,15 +1700,9 @@ carp_set_ifp(struct carp_softc *sc, stru
 		goto rm_dh;
 	}
 
-	cif = &ifp0->if_carp;
-	if (SRPL_EMPTY_LOCKED(cif)) {
-		if ((error = ifpromisc(ifp0, 1)))
-			goto rm_lh;
-
-	} else if (carp_check_dup_vhids(sc, cif, NULL)) {
-		error = EINVAL;
+	error = ifpromisc(ifp0, 1);
+	if (error != 0)
 		goto rm_lh;
-	}
 
 	/* detach from old interface */
 	if (sc->sc_carpdev != NULL)