Messages in this thread | | | Date | Wed, 14 Aug 2019 13:17:30 +0200 (CEST) | From | Jakub Jankowski <> | Subject | Re: [PATCH AUTOSEL 4.19 04/42] netfilter: conntrack: always store window size un-scaled |
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On 2019-08-14, Reindl Harald wrote:
> that's still not in 5.2.8
It will make its way into next 5.2.x release, as it is now in the pending queue: https://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/tree/queue-5.2
Regards, Jakub.
> > without the exception and "nf_conntrack_tcp_timeout_max_retrans = 60" a > vnc-over-ssh session having the VNC view in the background freezes > within 60 secods > > ----------------------------------------------------------------------------------------------- > IPV4 TABLE MANGLE (STATEFUL PRE-NAT/FILTER) > ----------------------------------------------------------------------------------------------- > Chain PREROUTING (policy ACCEPT 100 packets, 9437 bytes) > num pkts bytes target prot opt in out source > destination > 1 6526 3892K ACCEPT all -- * * 0.0.0.0/0 > 0.0.0.0/0 ctstate RELATED,ESTABLISHED > 2 125 6264 ACCEPT all -- lo * 0.0.0.0/0 > 0.0.0.0/0 > 3 64 4952 ACCEPT all -- vmnet8 * 0.0.0.0/0 > 0.0.0.0/0 > 4 1 40 DROP all -- * * 0.0.0.0/0 > 0.0.0.0/0 ctstate INVALID > > -------- Weitergeleitete Nachricht -------- > Betreff: [PATCH AUTOSEL 5.2 07/76] netfilter: conntrack: always store > window size un-scaled > > Am 08.08.19 um 11:02 schrieb Thomas Jarosch: >> Hello together, >> >> You wrote on Fri, Aug 02, 2019 at 09:22:24AM -0400: >>> From: Florian Westphal <fw@strlen.de> >>> >>> [ Upstream commit 959b69ef57db00cb33e9c4777400ae7183ebddd3 ] >>> >>> Jakub Jankowski reported following oddity: >>> >>> After 3 way handshake completes, timeout of new connection is set to >>> max_retrans (300s) instead of established (5 days). >>> >>> shortened excerpt from pcap provided: >>> 25.070622 IP (flags [DF], proto TCP (6), length 52) >>> 10.8.5.4.1025 > 10.8.1.2.80: Flags [S], seq 11, win 64240, [wscale 8] >>> 26.070462 IP (flags [DF], proto TCP (6), length 48) >>> 10.8.1.2.80 > 10.8.5.4.1025: Flags [S.], seq 82, ack 12, win 65535, [wscale 3] >>> 27.070449 IP (flags [DF], proto TCP (6), length 40) >>> 10.8.5.4.1025 > 10.8.1.2.80: Flags [.], ack 83, win 512, length 0 >>> >>> Turns out the last_win is of u16 type, but we store the scaled value: >>> 512 << 8 (== 0x20000) becomes 0 window. >>> >>> The Fixes tag is not correct, as the bug has existed forever, but >>> without that change all that this causes might cause is to mistake a >>> window update (to-nonzero-from-zero) for a retransmit. >>> >>> Fixes: fbcd253d2448b8 ("netfilter: conntrack: lower timeout to RETRANS seconds if window is 0") >>> Reported-by: Jakub Jankowski <shasta@toxcorp.com> >>> Tested-by: Jakub Jankowski <shasta@toxcorp.com> >>> Signed-off-by: Florian Westphal <fw@strlen.de> >>> Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> >>> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> >>> Signed-off-by: Sasha Levin <sashal@kernel.org> >> >> Also: >> Tested-by: Thomas Jarosch <thomas.jarosch@intra2net.com> >> >> ;) >> >> We've hit the issue with the wrong conntrack timeout at two different sites, >> long-lived connections to a SAP server over IPSec VPN were constantly dropping. >> >> For us this was a regression after updating from kernel 3.14 to 4.19. >> Yesterday I've applied the patch to kernel 4.19.57 and the problem is fixed. >> >> The issue was extra hard to debug as we could just boot the new kernel >> for twenty minutes in the evening on these productive systems. >> >> The stable kernel patch from last Friday came right on time. I was just >> about the replay the TCP connection with tcpreplay, so this saved >> me from another week of debugging. Thanks everyone! >
-- Jakub Jankowski|shasta@toxcorp.com|https://toxcorp.com/
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