Re: Fwd: question about using conntrack to change the mark

[Pablo Neira Ayuso <pablo@netfilter.org>]

On Tue, Aug 22, 2023 at 10:11:00AM +0800, Tony He wrote:
[...]
> I confirm this issue have been fixed. I even tried about 1000 flow entries.
> root@OpenWrt:~# ./conntrack -L -p tcp |wc -l
> conntrack v1.4.7 (conntrack-tools): 1024 flow entries have been shown.
> 1024
> root@OpenWrt:~# ./conntrack -U -p tcp  -m 1
> tcp      6 7423 ESTABLISHED src=192.168.1.30 dst=10.40.9.83
> sport=53786 dport=80 packets=2 bytes=112 src=10.40.9.83
> dst=10.40.9.165 sport=80 dport=53786 packets=1 bytes=60 [ASSURED]
> mark=1 use=2
> tcp      6 103 TIME_WAIT src=192.168.1.30 dst=10.40.9.83 sport=57656
> dport=80 packets=6 bytes=398 src=10.40.9.83 dst=10.40.9.165 sport=80
> dport=57656 packets=6 bytes=11265 [ASSURED] mark=1 use=2
> tcp      6 103 TIME_WAIT src=192.168.1.30 dst=10.40.9.83 sport=57000
> dport=80 packets=7 bytes=450 src=10.40.9.83 dst=10.40.9.165 sport=80
> dport=57000 packets=7 bytes=11317 [ASSURED] mark=1 use=2
> tcp      6 103 TIME_WAIT src=192.168.1.30 dst=10.40.9.83 sport=55730
> dport=80 packets=6 bytes=398 src=10.40.9.83 dst=10.40.9.165 sport=80
> dport=55730 packets=6 bytes=11265 [ASSURED] mark=1 use=2
> ......
> conntrack v1.4.7 (conntrack-tools): 1023 flow entries have been updated.
> 
> After above issue is fixed, I can not reproduce "-f ipv4" issue. Seems
> that we don't need patch
>
> https://patchwork.ozlabs.org/project/netfilter-devel/patch/20230821102739.4893-1-pablo@netfilter.org/

This is also required because conntrack -U/-D dumps the table from the
kernel, then it iterates over the list of entries. If the entry
expires, -U/-D will hit ENOENT, which should be ignored. This is
another regressions from 1.4.6.

> We only need
> https://patchwork.ozlabs.org/project/netfilter-devel/patch/20230821101751.4083-1-pablo@netfilter.org/
> and
> https://patchwork.ozlabs.org/project/netfilter-devel/patch/20230821120105.29538-1-pablo@netfilter.org/

Applied, thanks for reporting.

I have also pushed out this test:

  f088ba22246b ("tests/conntrack: add initial stress test for conntrack")

which covers these two bugs.