netfilter: nf_tables: reject mismatching sum of field_len with set key length

commit 1b9335a8000fb70742f7db10af314104b6ace220 upstream.

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 <noamr@ssd-disclosure.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Pablo Neira Ayuso 2025-01-28 12:26:33 +01:00 committed by Greg Kroah-Hartman
parent cbfb30ae17
commit 82e491e085
1 changed files with 4 additions and 4 deletions

View File

@ -4875,7 +4875,7 @@ 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;
@ -4889,12 +4889,12 @@ 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;