making secure limitations for non-root users

Tom Moore tom at
Fri Sep 19 17:52:58 EDT 2008

By default users can not read files in /var/log so you don't have to worry
about that.

If your running a system and don't trust the users who you are allowing on
to the system not to do anything wrong while you yourself are still learning
how to secure the system up you could be asking for real trouble.
Remember as a residential user and this may to apply to business users as
well you are responsible for anything that goes in to or out of your
internet connection, and if you don't trust who is actively using it at the
end of the day it could be your head on the chopping block when it comes to
issues with your isp.



-----Original Message-----
From: speakup-bounces at [mailto:speakup-bounces at]
On Behalf Of Tyler Littlefield
Sent: Friday, September 19, 2008 5:40 PM
To: Speakup is a screen review system for Linux.
Subject: Re: making secure limitations for non-root users

I'll dig around for that kernel patch.
Like, limiting them to viewing home dirs, other people's dirs. I can do 
chmod a-r /home, and then chmod o-rx /home/user, but would there be anything

else I'd need to limit for security reasons? I'd not like to scrue up perms 
on logs, but would rather not them see /var/log.

_|_|_|_|_|  _|        _|_|_|_|
    _|      _|_|_|    _|          _|_|_|
    _|      _|    _|  _|_|_|    _|
    _|      _|    _|  _|        _|
    _|      _|    _|  _|_|_|_|    _|_|_|
Visit TDS for quality software and website production
msn: tyler at
aim: st8amnd2005
skype: st8amnd127
----- Original Message ----- 
From: "Gregory Nowak" <greg at>
To: "Speakup is a screen review system for Linux." <speakup at>
Sent: Friday, September 19, 2008 3:38 PM
Subject: Re: making secure limitations for non-root users

> Hash: SHA1
> Tom has already told you what the best approach would be. However, let
> me try to specifically answer your questions.
> On Thu, Sep 18, 2008 at 12:39:40PM -0600, Tyler Littlefield wrote:
>> I would, however like to limit them in disk space (I can figure that
> one out),
> Ok.
>> in port usage (not sure how to do this one, would like to limit what
> ports they can open),
> The only thing I can think of for that is the obvious, a
> firewall. However, that would apply to everyone on the system. There
> is something called owner match support, when you're configuring the
> firewall stuff in the kernel, however, I'm not sure if that does what
> it actually suggests, or something else. Sorry, that's all I can tell
> you there, maybe a firewall howto somewhere would tell you more.
>> programs they can run,
> The best way I can think of to do that, is to create a group on your
> system, where all the binaries you want users to access are a part of
> that group. Then, add the users you want to be able to access those
> binaries to that group as well, and leave the rest binaries/users
> out. On my debian system, there is a group called bin, but most of my
> binaries are in root's group. I'm not sure if the bin group is
> reserved for something else, or if it is there for what its name
> suggests, and it's up to the system admin to use it as he/she wishes.
>> and also what they can view on the system.
> You need to be more specific. What do you want them to be able to
> view, man pages, text files, contents of specific directories, what?
> Greg
> - --
> web site:
> gpg public key:
> skype: gregn1
> (authorization required, add me to your contacts list first)
> - --
> Free domains: or mail dns-manager at
> Version: GnuPG v1.4.9 (GNU/Linux)
> iEYEARECAAYFAkjUG8gACgkQ7s9z/XlyUyDY8QCeMyiUbYUWG+XeixZqmeq2vnxW
> zckAoLvhv/znPYpTPB1hr6BxFVZl81/r
> =+v8G
> _______________________________________________
> Speakup mailing list
> Speakup at
> __________ NOD32 3457 (20080919) Information __________
> This message was checked by NOD32 antivirus system.

Speakup mailing list
Speakup at

More information about the Speakup mailing list