NF_CT_EXT_NAT
return nf_ct_ext_find(ct, NF_CT_EXT_NAT);
[NF_CT_EXT_NAT] = sizeof(struct nf_conn_nat),
struct nf_conn_nat *nat = nf_ct_ext_find(ct, NF_CT_EXT_NAT);
if (!nat && !nf_ct_ext_add(ct, NF_CT_EXT_NAT, GFP_ATOMIC))
nat = nf_ct_ext_add(ct, NF_CT_EXT_NAT, GFP_ATOMIC);