NETMAP_REQ_MAXSIZE
if (rqsz > NETMAP_REQ_MAXSIZE) {
bufsz = (2 + NETMAP_REQ_OPT_MAX) * sizeof(void *) + NETMAP_REQ_MAXSIZE +
if ((optsz > NETMAP_REQ_MAXSIZE) || (opt->nro_size > NETMAP_REQ_MAXSIZE)
|| (rqsz + optsz > NETMAP_REQ_MAXSIZE)