Re: allowing a "normal" user to work efficiently

[Deryk Barker <dbarker@turing.cs.camosun.bc.ca>]

Thus spake Ken Bloom (kabloom@ucdavis.edu):

> On Tue, 21 Oct 2003 18:20:22 +0200, Bijan Soleymani wrote:
> 
> > On Tue, Oct 21, 2003 at 11:34:52AM -0400, Roberto Sanchez wrote:
> > For example imagine you make "cat" suid...
> > 
> > Then someone can do:
> > cat /bin/rm /bin/cat
> 
> Interesting attack in theory, but it doesn't work.
> the correct command is cat /bin/rm > /bin/cat
> and when you run that command, the pipe is handled by the unprivileged
> shell.
> 
> > cat -rf /

Ah, but there's another thing: overwriting a setuid file turns the
setuid bit off. (I think this was originally put into *nix for C2
certification) So it still wouldn't work.

-- 
|Deryk Barker, Computer Science Dept. | Music does not have to be understood|
|Camosun College, Victoria, BC, Canada| It has to be listened to.           |
|email: dbarker@camosun.bc.ca         |                                     |
|phone: +1 250 370 4452               |         Hermann Scherchen.          |