From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: Horrible denial of service bug in autmount 5
Date: Fri, 20 Jun 2008 12:03:28 -0700
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To: Ian Kent <raven@themaw.net>
Cc: autofs@linux.kernel.org, Anton Altaparmakov <aia21@cam.ac.uk>, Unix Support <unix-support@ucs.cam.ac.uk>

Ian Kent wrote:
>> Okay, I'm confused... what reason could there *possibly* be for 
>> searching /proc/*/cmdline? If there is a need for a mutex of some sort, 
>> one should typically create a /var/run directory and put in lock files, 
>> or some other solution to test the mutexing explicitly.  grepping ps, in 
>> effect, is hardly a good idea, to put it gently.
> 
> This is nothing more than a check to see if another instance of
> automount(8) is running.

But it is an utterly daft way to implement something like that.  If you 
want a lock, create an explicit lock, but doing string-matching on 
command lines is idiotic.

	-hpa