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Date: Mon, 7 Apr 2014 07:25:22 -0500
From: Mark Felder <feld@freebsd.org>
To: freebsd-hackers@freebsd.org
Subject: Re: pipe() resource exhaustion
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On 2014-04-07 06:02, Ivan Voras wrote:
> Hello,
> 
> Last time I mentioned this it didn't get any attention, so I'll try
> again. By accident (via a buggy synergy server process) I found that a
> simple userland process can exhaust kernel pipe memory 
> (kern.ipc.pipekva
> sysctl) which as a consequence has that new processes which use pipe
> cannot be started, which includes "su", by which an administrator could
> kill such a process.
> 

That's a pretty painful local denial of service :(