netdev - Re: After a while of system running no incoming UDP any more?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 24 Jul 2017 16:19:10 +0200
From:   Paolo Abeni <pabeni@...hat.com>
To:     Marc Haber <mh+netdev@...schlus.de>, netdev@...r.kernel.org
Subject: Re: After a while of system running no incoming UDP any more?

Hi,

On Mon, 2017-07-24 at 14:09 +0200, Marc Haber wrote:
> Before I begin running older kernels on productive systems, I would like
> to ask wether there have been recent changes in the 4.11 => 4.12
> development cycle that might cause an issue like that.

While there has been some activity regarding the UDP protocol lately,
almost nothing touched UDP in the 4.11 release cycle.

The issue you describe looks similar to the bug fixed by the commit
9bd780f5e066 ("udp: fix poll()"), but the bugged code is only in later
kernels. 

> Any idea what might be happening here and what else I could try?

Once that a system enter the buggy status, do the packets reach the
relevant socket's queue?

ss -u
nstat |grep -e Udp -e Ip

will help checking that.

Thanks,

Paol