lro_tcp_h_off
m->m_pkthdr.lro_tcp_h_off = ((uint8_t *)th - (uint8_t *)m->m_data);
m->m_pkthdr.lro_tcp_h_off));
tcp_hdr_offset = m->m_pkthdr.lro_tcp_h_off;
m->m_pkthdr.lro_tcp_h_off -= tcp_hdr_offset;