On Thu, Jan 19, 2006 at 05:11:33PM +0200, Efraim Yawitz wrote:
> The system call mknod can only be used by root to make special
> device files, but once those files exist they can be copied by
> anyone. What is to stop me from becoming root on my own machine and
> creating a whole set of /dev files which are world-readable and
> writable, putting them in a tar archive and then untarring that on
> another machine where I would now have raw access to all the
> devices. It seems like the only safeguard against such a thing
> would be to prevent users from bringing any files into the system,
> but this is ridiculous if Internet access is to be allowed.
>
> Any reactions? Am I making some obvious mistake?
(as me, not root) tar cvf - -C /dev fd0 |tar xvf -
fd0
fd0
tar: fd0: Cannot mknod: Operation not permitted
tar: Error exit delayed from previous errors
Seems like you are ok.
Geoff.
--
Geoffrey S. Mendelson, Jerusalem, Israel [EMAIL PROTECTED] N3OWJ/4X1GM
IL Voice: (07)-7424-1667 IL Fax: 972-2-648-1443 U.S. Voice: 1-215-821-1838
The trouble with being a futurist is that when people get around to believing
you, it's too late. We lost. Google 2,000,000:Hams 0.
=================================================================
To unsubscribe, send mail to [EMAIL PROTECTED] with
the word "unsubscribe" in the message body, e.g., run the command
echo unsubscribe | mail [EMAIL PROTECTED]
