From 3ce67e3793f48c1b9635beb9bb71116ca1e51b58 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Sun, 14 Jan 2024 23:53:39 +0100 Subject: netfilter: nf_tables: do not allow mismatch field size and set key length The set description provides the size of each field in the set whose sum should not mismatch the set key length, bail out otherwise. I did not manage to crash nft_set_pipapo with mismatch fields and set key length so far, but this is UB which must be disallowed. Fixes: f3a2181e16f1 ("netfilter: nf_tables: Support for sets with multiple ranged fields") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'net/netfilter/nf_tables_api.c') diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 50b595ef6389..e9fa4a32c093 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -4813,8 +4813,8 @@ static int nft_set_desc_concat_parse(const struct nlattr *attr, static int nft_set_desc_concat(struct nft_set_desc *desc, const struct nlattr *nla) { + u32 num_regs = 0, key_num_regs = 0; struct nlattr *attr; - u32 num_regs = 0; int rem, err, i; nla_for_each_nested(attr, nla, rem) { @@ -4829,6 +4829,10 @@ static int nft_set_desc_concat(struct nft_set_desc *desc, for (i = 0; i < desc->field_count; i++) num_regs += DIV_ROUND_UP(desc->field_len[i], sizeof(u32)); + key_num_regs = DIV_ROUND_UP(desc->klen, sizeof(u32)); + if (key_num_regs != num_regs) + return -EINVAL; + if (num_regs > NFT_REG32_COUNT) return -E2BIG; -- cgit