netfilter: nf_tables: check NFT_SET_CONCAT flag if field_count is specified

Since f3a2181e16f1 ("netfilter: nf_tables: Support for sets with
multiple ranged fields"), it possible to combine intervals and
concatenations. Later on, ef516e8625dd ("netfilter: nf_tables:
reintroduce the NFT_SET_CONCAT flag") provides the NFT_SET_CONCAT flag
for userspace to report that the set stores a concatenation.

Make sure NFT_SET_CONCAT is set on if field_count is specified for
consistency. Otherwise, if NFT_SET_CONCAT is specified with no
field_count, bail out with EINVAL.

Fixes: ef516e8625dd ("netfilter: nf_tables: reintroduce the NFT_SET_CONCAT flag")
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 b1b12e0..62cfb0e 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4451,6 +4451,11 @@ static int nf_tables_newset(struct sk_buff *skb, const struct nfnl_info *info,
                err = nf_tables_set_desc_parse(&desc, nla[NFTA_SET_DESC]);
                if (err < 0)
                        return err;
+
+               if (desc.field_count > 1 && !(flags & NFT_SET_CONCAT))
+                       return -EINVAL;
+       } else if (flags & NFT_SET_CONCAT) {
+               return -EINVAL;
        }
 
        if (nla[NFTA_SET_EXPR] || nla[NFTA_SET_EXPRESSIONS])