netfilter, bpf: Adjust timeouts of non-confirmed CTs in bpf_ct_insert_entry()

[ Upstream commit 837723b22a63cfbff584655b009b9d488d0e9087 ]

bpf_nf testcase fails on s390x: bpf_skb_ct_lookup() cannot find the entry
that was added by bpf_ct_insert_entry() within the same BPF function.

The reason is that this entry is deleted by nf_ct_gc_expired().

The CT timeout starts ticking after the CT confirmation; therefore
nf_conn.timeout is initially set to the timeout value, and
__nf_conntrack_confirm() sets it to the deadline value.

bpf_ct_insert_entry() sets IPS_CONFIRMED_BIT, but does not adjust the
timeout, making its value meaningless and causing false positives.

Fix the problem by making bpf_ct_insert_entry() adjust the timeout,
like __nf_conntrack_confirm().

Fixes: 2cdaa3eefed8 ("netfilter: conntrack: restore IPS_CONFIRMED out of nf_conntrack_hash_check_insert()")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/bpf/20230830011128.1415752-3-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Gbp-Pq: Topic bugfix/all
Gbp-Pq: Name netfilter-bpf-adjust-timeouts-of-non-confirmed-cts-i.patch

diff --git a/net/netfilter/nf_conntrack_bpf.c b/net/netfilter/nf_conntrack_bpf.c
index 8639e7efd0e22e5c4afd837f5191421b7be69629..816283f0aa593149691f3cbad15bdc6916b1ffdc 100644 (file)
--- a/net/netfilter/nf_conntrack_bpf.c
+++ b/net/netfilter/nf_conntrack_bpf.c
@@ -384,6 +384,8 @@ struct nf_conn *bpf_ct_insert_entry(struct nf_conn___init *nfct_i)
        struct nf_conn *nfct = (struct nf_conn *)nfct_i;
        int err;
 
+       if (!nf_ct_is_confirmed(nfct))
+               nfct->timeout += nfct_time_stamp;
        nfct->status |= IPS_CONFIRMED;
        err = nf_conntrack_hash_check_insert(nfct);
        if (err < 0) {