Re: unable to attach to setuid program that as reverted it privilege

Mark Kettenis
2008-01-23T17:52:51Z

> Date: Tue, 22 Jan 2008 13:59:48 -0600
> From: "Michael Potter" <pottmi@gmail.com>
>
> Gdb Crew,
>
> I get this error when attaching to a setuid program that has
> _given_up_ its root privilege setuid(getuid()):
>
> ---------------------
> x~> gdb -p 19484
> GNU gdb 6.5
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> This GDB was configured as "i586-suse-linux".
> Attaching to process 19484
> ptrace: Operation not permitted. <<<<<=================

This is the only acceptable behaviour. The program might have dropped
root priviliges but it might still hold resources acquired when it
still had those priviliges and you might be able to exploit those.

You should be able to attach to the process as root. If not, complain
to the Linux kernel people.