netfilter: nftables: add helper function to validate set element data

When binding sets to rule, validate set element data according to
set definition. This patch adds a helper function to be reused by
the catch-all set element support.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nf_tables_api.c

@@ -4499,10 +4499,9 @@ static int nft_validate_register_store(const struct nft_ctx *ctx,
 				       enum nft_data_types type,
 				       unsigned int len);
 
-static int nf_tables_bind_check_setelem(const struct nft_ctx *ctx,
-					struct nft_set *set,
-					const struct nft_set_iter *iter,
-					struct nft_set_elem *elem)
+static int nft_setelem_data_validate(const struct nft_ctx *ctx,
+				     struct nft_set *set,
+				     struct nft_set_elem *elem)
 {
 	const struct nft_set_ext *ext = nft_set_elem_ext(set, elem->priv);
 	enum nft_registers dreg;
@@ -4514,6 +4513,14 @@ static int nf_tables_bind_check_setelem(const struct nft_ctx *ctx,
 					   set->dlen);
 }
 
+static int nf_tables_bind_check_setelem(const struct nft_ctx *ctx,
+					struct nft_set *set,
+					const struct nft_set_iter *iter,
+					struct nft_set_elem *elem)
+{
+	return nft_setelem_data_validate(ctx, set, elem);
+}
+
 int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set,
 		       struct nft_set_binding *binding)
 {