Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 26 Jul 2005 09:17:17 -0500
From:      Eric Anderson <anderson@centtech.com>
To:        bv@wjv.com
Cc:        freebsd-isp@freebsd.org
Subject:   Re: preventing a user to start a process
Message-ID:  <42E645ED.8050408@centtech.com>
In-Reply-To: <20050726141149.GC14374@wjv.com>
References:  <42E54654.1090705@chef-ingenieur.de> <42E549E7.4070606@centtech.com> <20050726141149.GC14374@wjv.com>

next in thread | previous in thread | raw e-mail | index | archive | help
Bill Vermillion wrote:
> -segmentation fault- 
> press any key to reboot 
> Damn damn damn Eric Anderson said, after restarting his 
> PC and mailer on Mon, Jul 25, 2005 at 15:21 .
> 
> 
>>Thomas Krause wrote:
>>
>>>Hello,
>>>is it possible to bar a user (www) from starting a process?
>>>I've a irc daemon running under the uid www. I think
>>>this was done by php. What would be the best way to prevent
>>>this (php should be remain usable)? I've installed ipfw rules,
>>>but this doesn't prevent the starting of the process.
> 
> 
>>Change the permissions on the file to not allow world execution?
> 
> 
>>chmod 750 /path/to/irc-daemon
> 
> 
>>and make sure it isn't owner by www user, and the www user is not in the 
>>group that owns the daemon.
> 
> 
> Well that would mean that anyone else who might need to execute
> that file can only do so if they 1) own it or 2) are in the group.
> 
> To get around this change the modes of the program in a way that is
> non-intuitive.
> 
> Change the group of that daemon to www and the change the mode
> to 705.  Since this evaluates left to right it will fail at www
> while all others will be able to use the file.  This seems to be
> overlooked by many who think that 'world' means everyone, while
> it means everyone who doesn't match in owner or group.

Ahh, great idea.. Unfortunately, his problem was worse than our 
solutions :(

Eric




-- 
------------------------------------------------------------------------
Eric Anderson        Sr. Systems Administrator        Centaur Technology
A lost ounce of gold may be found, a lost moment of time never.
------------------------------------------------------------------------



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?42E645ED.8050408>