CGW_FDMOD_XOR
if (nla_put(skb, CGW_FDMOD_XOR, sizeof(mb), &mb) < 0)
[CGW_FDMOD_XOR] = { .len = sizeof(struct cgw_fdframe_mod) },
if (tb[CGW_FDMOD_XOR]) {
nla_memcpy(&mb, tb[CGW_FDMOD_XOR], CGW_FDMODATTR_LEN);