Re: O_NOLINK for open()

Bodo Eggert
2007-09-14T17:26:49Z

On Fri, 14 Sep 2007, Andreas Schwab wrote:
> Bodo Eggert <7eggert@gmx.de> writes:

> > ~/tmp > cp /bin/sleep .
> > ~/tmp > chmod u+s sleep
> > ~/tmp > ./sleep 2147483647 &
> > [1] 2823
> > ~/tmp > strace -p 2823
> > Process 2823 attached - interrupt to quit
> > setup(
>
> You didn't change the owner, so this is not a setuid execution.

I expected that, but I wanted to be sure before telling bull****.
Besides that, if the suid program was owned by the suid-to user,
that user could modify the binary in order to prepare a future attack.
--
Top 100 things you don't want the sysadmin to say:
16. find /usr2 -name nethack -exec rm -f {};