netfilter: ctnetlink: use helper function to calculate expect ID

Delete expectation path is missing a call to the nf_expect_get_id()
helper function to calculate the expectation ID, otherwise LSB of the
expectation object address is leaked to userspace.

Fixes: 3c79107631 ("netfilter: ctnetlink: don't use conntrack/expect object addresses as id")
Reported-by: zdi-disclosures@trendmicro.com
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Pablo Neira Ayuso 2024-07-13 16:47:38 +02:00
parent 0e03c643dc
commit 782161895e

View file

@ -3420,7 +3420,8 @@ static int ctnetlink_del_expect(struct sk_buff *skb,
if (cda[CTA_EXPECT_ID]) {
__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
if (ntohl(id) != (u32)(unsigned long)exp) {
if (id != nf_expect_get_id(exp)) {
nf_ct_expect_put(exp);
return -ENOENT;
}