MLPIPHDRLEN
#if !defined(MLPIPHDRLEN) || LPIPHDRLEN > MLPIPHDRLEN
sc->sc_ifbuf = kmalloc(sc->sc_if.if_mtu + MLPIPHDRLEN,
sc->sc_ifbuf = kmalloc(ifr->ifr_mtu+MLPIPHDRLEN, M_DEVBUF, M_WAITOK);
if (len > sc->sc_if.if_mtu + MLPIPHDRLEN)