From: Pablo Neira Ayuso Date: Tue, 28 Jan 2025 11:26:33 +0000 (+0100) Subject: netfilter: nf_tables: reject mismatching sum of field_len with set key length X-Git-Tag: v6.14-rc1~33^2^2 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1b9335a8000fb70742f7db10af314104b6ace220;p=thirdparty%2Flinux.git netfilter: nf_tables: reject mismatching sum of field_len with set key length The field length description provides the length of each separated key field in the concatenation, each field gets rounded up to 32-bits to calculate the pipapo rule width from pipapo_init(). The set key length provides the total size of the key aligned to 32-bits. Register-based arithmetics still allows for combining mismatching set key length and field length description, eg. set key length 10 and field description [ 5, 4 ] leading to pipapo width of 12. Cc: stable@vger.kernel.org Fixes: 3ce67e3793f4 ("netfilter: nf_tables: do not allow mismatch field size and set key length") Reported-by: Noam Rathaus Reviewed-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index c4af283356e74..e5662dc087c8c 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -5065,7 +5065,7 @@ 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; + u32 len = 0, num_regs; struct nlattr *attr; int rem, err, i; @@ -5079,12 +5079,12 @@ 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)); + len += round_up(desc->field_len[i], sizeof(u32)); - key_num_regs = DIV_ROUND_UP(desc->klen, sizeof(u32)); - if (key_num_regs != num_regs) + if (len != desc->klen) return -EINVAL; + num_regs = DIV_ROUND_UP(desc->klen, sizeof(u32)); if (num_regs > NFT_REG32_COUNT) return -E2BIG;