Subject: Re: denial of service shell script
To: Emmanuel Dreyfus <manu@netbsd.org>
From: Greg A. Woods <woods@weird.com>
List: tech-kern
Date: 12/18/2001 16:04:32
[ On Tuesday, December 18, 2001 at 20:03:36 (+0100), Emmanuel Dreyfus wrote: ]
> Subject: Re: denial of service shell script
>
> I don't really understand why, the script is able to eat 501 processes
> and it fills the whole table. The processes remain here when I log out,
> leaving the machine in a state where root cannot even log in.

How can't root login?  If you mean on the console or other hard-wired
terminal marked "secure" then there's definitely something wrong at a
much deeper level than the process table being filled.  Logging in on
such a tty normally does not require any new processes to be created.
'getty' execs 'login', which execs root's shell.  There's also always
supposed to be one slot left that only root can use (though I haven't
verified if this is still true on NetBSD).  What else was running as
root on your system?  I.e. was anything else running as root which could
have been forking new processes?

> the fifo stuff result is a bit unexpected. It's probably a local setup
> problem, but I'd like to understand what is wrong.

what else (that you think might be significant) is different about your
system from a default install?

-- 
								Greg A. Woods

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