Posted by Jerry Stuckle on 12/05/07 12:23

Toby A Inkster wrote:
> Jerry Stuckle wrote:
>
>> If your system is set up properly, inly the owner or root can chown() a
>> file.
>
> Actually, unless you've set your system up unusually, only root can.
>
> Technically, the owner of the file *can* chown it, but they can't assign
> ownership to any other user -- they can only chown it to themself, which
> is rather pointless.
>
> In short, unless you're root, you can't use chown to assign ownership to
> someone else.
>
> This is for very valid security reasons. You could, for instance, write
> and compile a C program which did the equivalent of "rm -fr /", give it
> permissions 4755 (executable and readable, with setuid bit), chown it to
> root and then run it, wiping out the entire system.
>

Nope, I can do it just find on my system. But your idea of rm -fr won't
work - the script will execute under the user's permissions. You would
have to change the su bit on the shell's executable - and only root can
do that.

Even chown'ing it to root will not make any difference as far as the
script goes. Ownership of the script does not affect permissions of the
user running the script.

--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attglobal.net
==================

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