PFLOW_SET_HDRLEN
m_copyback(m, 0, PFLOW_SET_HDRLEN, (caddr_t)&set_hdr);
m_copyback(sc->sc_mbuf, PFLOW_SET_HDRLEN +
m_copyback(sc->sc_mbuf6, PFLOW_SET_HDRLEN +
m_copyback(sc->sc_mbuf_nat4, PFLOW_SET_HDRLEN +