Re: PATCH: proc_do_stop and rpctrace

[Marcus Brinkmann]

On Sat, Aug 09, 2003 at 05:33:29PM -0400, Roland McGrath wrote:
> The concern I have about this patch per se is proc calling thread_resume on
> a random port from the user.  This is at least a DoS opportunity.

Oh yeah, that's true, and I admit I didn't really think of it.

> It also
> points to a more general problem rpctrace has--servers make comparisons
> between ports from the user (rpctrace) and ports outside rpctrace's sphere
> of interposition.  I bet "rpctrace ln foo bar" (dir_link) gets EXDEV too.

That could be expected.  This is probably unfixable.

I have mixed feelings about this.  One thing is that there are lots of
problems in the Hurd like the DoS attack above.  But of course that's not
really a good reason to put in another one.  So if you think I should revert
the patch, I will do.

For the future, I am really working on the L4 port, and there things will be
different enough to not worry much about what would be a way to do it in
Mach. 

Thanks,
Marcus


-- 
`Rhubarb is no Egyptian god.' GNU      http://www.gnu.org    address@hidden
Marcus Brinkmann              The Hurd http://www.gnu.org/software/hurd/
address@hidden
http://www.marcus-brinkmann.de/