From: Pablo Neira Ayuso <pablo@netfilter.org> stable inclusion from stable-5.10.80 commit bc9199271c32ec104eac405f7d412283b86e0440 bugzilla: 185821 https://gitee.com/openeuler/kernel/issues/I4L7CG Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit b7b1d02fc43925a4d569ec221715db2dfa1ce4f5 ] The internal stream state sets the timeout to 120 seconds 2 seconds after the creation of the flow, attach this internal stream state to the IPS_ASSURED flag for consistent event reporting. Before this patch: [NEW] udp 17 30 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 [UNREPLIED] src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [UPDATE] udp 17 30 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [UPDATE] udp 17 30 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [ASSURED] [DESTROY] udp 17 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [ASSURED] Note IPS_ASSURED for the flow not yet in the internal stream state. after this update: [NEW] udp 17 30 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 [UNREPLIED] src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [UPDATE] udp 17 30 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [UPDATE] udp 17 120 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [ASSURED] [DESTROY] udp 17 src=10.246.11.13 dst=216.239.35.0 sport=37282 dport=123 src=216.239.35.0 dst=10.246.11.13 sport=123 dport=37282 [ASSURED] Before this patch, short-lived UDP flows never entered IPS_ASSURED, so they were already candidate flow to be deleted by early_drop under stress. Before this patch, IPS_ASSURED is set on regardless the internal stream state, attach this internal stream state to IPS_ASSURED. packet #1 (original direction) enters NEW state packet #2 (reply direction) enters ESTABLISHED state, sets on IPS_SEEN_REPLY paclet #3 (any direction) sets on IPS_ASSURED (if 2 seconds since the creation has passed by). Reported-by: Maciej Żenczykowski <zenczykowski@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Reviewed-by: Weilong Chen <chenweilong@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- net/netfilter/nf_conntrack_proto_udp.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/net/netfilter/nf_conntrack_proto_udp.c b/net/netfilter/nf_conntrack_proto_udp.c index af402f458ee0..0528e9c26ceb 100644 --- a/net/netfilter/nf_conntrack_proto_udp.c +++ b/net/netfilter/nf_conntrack_proto_udp.c @@ -105,10 +105,13 @@ int nf_conntrack_udp_packet(struct nf_conn *ct, */ if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) { unsigned long extra = timeouts[UDP_CT_UNREPLIED]; + bool stream = false; /* Still active after two seconds? Extend timeout. */ - if (time_after(jiffies, ct->proto.udp.stream_ts)) + if (time_after(jiffies, ct->proto.udp.stream_ts)) { extra = timeouts[UDP_CT_REPLIED]; + stream = true; + } nf_ct_refresh_acct(ct, ctinfo, skb, extra); @@ -117,7 +120,7 @@ int nf_conntrack_udp_packet(struct nf_conn *ct, return NF_ACCEPT; /* Also, more likely to be important, and not a probe */ - if (!test_and_set_bit(IPS_ASSURED_BIT, &ct->status)) + if (stream && !test_and_set_bit(IPS_ASSURED_BIT, &ct->status)) nf_conntrack_event_cache(IPCT_ASSURED, ct); } else { nf_ct_refresh_acct(ct, ctinfo, skb, timeouts[UDP_CT_UNREPLIED]); -- 2.20.1