netfilter: nf_tables: add nft_expr_type_request_module()

This helper function makes sure the family specific extension is loaded.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index cae5c46e2dd460b585f2ecf77e92c7a6cfead6a4..582f4e475d6773475df8194535ea95deb8e11929 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2019,6 +2019,19 @@ static const struct nft_expr_type *__nft_expr_type_get(u8 family,
        return NULL;
 }
 
+#ifdef CONFIG_MODULES
+static int nft_expr_type_request_module(struct net *net, u8 family,
+                                       struct nlattr *nla)
+{
+       nft_request_module(net, "nft-expr-%u-%.*s", family,
+                          nla_len(nla), (char *)nla_data(nla));
+       if (__nft_expr_type_get(family, nla))
+               return -EAGAIN;
+
+       return 0;
+}
+#endif
+
 static const struct nft_expr_type *nft_expr_type_get(struct net *net,
                                                     u8 family,
                                                     struct nlattr *nla)
@@ -2035,9 +2048,7 @@ static const struct nft_expr_type *nft_expr_type_get(struct net *net,
        lockdep_nfnl_nft_mutex_not_held();
 #ifdef CONFIG_MODULES
        if (type == NULL) {
-               nft_request_module(net, "nft-expr-%u-%.*s", family,
-                                  nla_len(nla), (char *)nla_data(nla));
-               if (__nft_expr_type_get(family, nla))
+               if (nft_expr_type_request_module(net, family, nla) == -EAGAIN)
                        return ERR_PTR(-EAGAIN);
 
                nft_request_module(net, "nft-expr-%.*s",