CentOS - Mar 2012 - How to restrict reboot/poweroff from non-admins?

I just noticed that CentOS (6.2) by default allows any user to 
reboot/poweroff system without any admin rights, or without any further 
questions, if using commands 'reboot' or 'poweroff'. But
'shutdown' still
requires admin rights.

What is the preferred way to restrict any regular user from rebooting / 
powering off the system (by accident)?

IMHO, sudo should be required for this purpose (at least in a system with 
shared remote access from multiple users, single-user laptops etc may be a 
different case)

--
TiN

Timo Neuvonen wrote on 03/28/2012 09:17 AM:
> I just noticed that CentOS (6.2) by default allows any user to
> reboot/poweroff system without any admin rights, or without any further
> questions, if using commands 'reboot' or 'poweroff'. But
'shutdown' still
> requires admin rights.
>
> What is the preferred way to restrict any regular user from rebooting /
> powering off the system (by accident)?
>
> IMHO, sudo should be required for this purpose (at least in a system with
> shared remote access from multiple users, single-user laptops etc may be a
> different case)
>
OUCH! This seems to qualify as a CentOS bug.  I confirm that a normal 
user can reboot or poweroff the system on 6.2.  On RHEL:

$ rpm -qa redhat-release\*
redhat-release-server-6Server-6.2.0.3.el6.x86_64
$ poweroff
poweroff: Need to be root
$ reboot
reboot: Need to be root

Phil