diff --git a/sys/contrib/ipfilter/netinet/ip_fil_freebsd.c b/sys/contrib/ipfilter/netinet/ip_fil_freebsd.c
index 292a119e2c43..dce75517dd63 100644
--- a/sys/contrib/ipfilter/netinet/ip_fil_freebsd.c
+++ b/sys/contrib/ipfilter/netinet/ip_fil_freebsd.c
@@ -135,8 +135,8 @@ ipf_check_wrapper(struct mbuf **mp, struct ifnet *ifp, int flags,
 	pfil_return_t rv;
 
 	CURVNET_SET(ifp->if_vnet);
-	rv = ipf_check(&V_ipfmain, ip, ip->ip_hl << 2, ifp, (flags & PFIL_OUT),
-	    mp);
+	rv = ipf_check(&V_ipfmain, ip, ip->ip_hl << 2, ifp,
+	    !!(flags & PFIL_OUT), mp);
 	CURVNET_RESTORE();
 	return (rv == 0 ? PFIL_PASS : PFIL_DROPPED);
 }
@@ -150,7 +150,7 @@ ipf_check_wrapper6(struct mbuf **mp, struct ifnet *ifp, int flags,
 
 	CURVNET_SET(ifp->if_vnet);
 	rv = ipf_check(&V_ipfmain, mtod(*mp, struct ip *),
-	    sizeof(struct ip6_hdr), ifp, (flags & PFIL_OUT), mp);
+	    sizeof(struct ip6_hdr), ifp, !!(flags & PFIL_OUT), mp);
 	CURVNET_RESTORE();
 
 	return (rv == 0 ? PFIL_PASS : PFIL_DROPPED);