This is a note to let you know that I've just added the patch titled
netfilter: nf_tables: do not allow mismatch field size and set key length
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
netfilter-nf_tables-do-not-allow-mismatch-field-size.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 50f596b1aa53ba7f6c15d6554c5c364178776ec9
Author: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Date: Sun Jan 14 23:53:39 2024 +0100
netfilter: nf_tables: do not allow mismatch field size and set key length
[ Upstream commit 3ce67e3793f48c1b9635beb9bb71116ca1e51b58 ]
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 <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index e1a06d5a386f..9f22f62a9b4d 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4453,8 +4453,8 @@ 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) {
@@ -4469,6 +4469,10 @@ 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;
