netfilter: nf_tables_offload: return EOPNOTSUPP if rule specifies no actions

If the rule only specifies the matching side, return EOPNOTSUPP.
Otherwise, the front-end relies on the drivers to reject this rule.

Fixes: c9626a2cbdb2 ("netfilter: nf_tables: add hardware offload support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nf_tables_offload.c b/net/netfilter/nf_tables_offload.c
index d7a35da..22fb189 100644 (file)
--- a/net/netfilter/nf_tables_offload.c
+++ b/net/netfilter/nf_tables_offload.c
@@ -44,6 +44,9 @@ struct nft_flow_rule *nft_flow_rule_create(struct net *net,
                expr = nft_expr_next(expr);
        }
 
+       if (num_actions == 0)
+               return ERR_PTR(-EOPNOTSUPP);
+
        flow = nft_flow_rule_alloc(num_actions);
        if (!flow)
                return ERR_PTR(-ENOMEM);