From bf5355cfdede3e30b30e63a5a74f6bdaafb26082 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Fri, 26 Jun 2026 13:40:42 +0200 Subject: [PATCH] netfilter: nfnetlink_cthelper: cap to maximum number of expectation per master If userspace helper policy updates sets maximum number of expectation to zero, cap it to NF_CT_EXPECT_MAX_CNT (255) on updates too. Fixes: 397c8300972f ("netfilter: nf_conntrack_helper: cap maximum number of expectation at helper registration") Signed-off-by: Pablo Neira Ayuso Signed-off-by: Florian Westphal --- net/netfilter/nfnetlink_cthelper.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c index f1460b683d7a..2cbcca9110db 100644 --- a/net/netfilter/nfnetlink_cthelper.c +++ b/net/netfilter/nfnetlink_cthelper.c @@ -163,6 +163,8 @@ nfnl_cthelper_expect_policy(struct nf_conntrack_expect_policy *expect_policy, tb[NFCTH_POLICY_NAME], NF_CT_HELPER_NAME_LEN); expect_policy->max_expected = ntohl(nla_get_be32(tb[NFCTH_POLICY_EXPECT_MAX])); + if (!expect_policy->max_expected) + expect_policy->max_expected = NF_CT_EXPECT_MAX_CNT; if (expect_policy->max_expected > NF_CT_EXPECT_MAX_CNT) return -EINVAL;