+int __nf_ct_try_assign_helper(struct nf_conn *ct, gfp_t flags)
+{
+ int ret = 0;
+ struct nf_conntrack_helper *helper;
+ struct nf_conn_help *help = nfct_help(ct);
+
+ helper = __nf_ct_helper_find(&ct->tuplehash[IP_CT_DIR_REPLY].tuple);
+ if (helper == NULL) {
+ if (help)
+ rcu_assign_pointer(help->helper, NULL);
+ goto out;
+ }
+
+ if (help == NULL) {
+ help = nf_ct_helper_ext_add(ct, flags);
+ if (help == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ } else {
+ memset(&help->help, 0, sizeof(help->help));
+ }
+
+ rcu_assign_pointer(help->helper, helper);
+out:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__nf_ct_try_assign_helper);
+