Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id <S129480AbQK3Vxg>; Thu, 30 Nov 2000 16:53:36 -0500
Received: (majordomo@vger.kernel.org) by vger.kernel.org
	id <S130146AbQK3Vx0>; Thu, 30 Nov 2000 16:53:26 -0500
Received: from sith.mimuw.edu.pl ([193.0.97.1]:18950 "HELO sith.mimuw.edu.pl")
	by vger.kernel.org with SMTP id <S129480AbQK3VxP>;
	Thu, 30 Nov 2000 16:53:15 -0500
Date: Thu, 30 Nov 2000 22:24:22 +0100
From: Jan Rekorajski <baggins@sith.mimuw.edu.pl>
To: Pavel Machek <pavel@suse.cz>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] no RLIMIT_NPROC for root, please
Message-ID: <20001130222422.E2605@sith.mimuw.edu.pl>
Mail-Followup-To: Jan Rekorajski <baggins@sith.mimuw.edu.pl>,
	Pavel Machek <pavel@suse.cz>, linux-kernel@vger.kernel.org
In-Reply-To: <20001128214309.F2680@sith.mimuw.edu.pl> <Pine.LNX.4.21.0011282049470.1940-100000@penguin.homenet> <20001128221155.G2680@sith.mimuw.edu.pl> <20001130010057.B124@bug.ucw.cz>
Mime-Version: 1.0
Content-Type: text/plain; charset=iso-8859-2
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
User-Agent: Mutt/1.2.5i
In-Reply-To: <20001130010057.B124@bug.ucw.cz>; from pavel@suse.cz on Thu, Nov 30, 2000 at 01:00:57AM +0100
X-Operating-System: Linux 2.4.0-test11-pre6 i686
Sender: linux-kernel-owner@vger.kernel.org
X-Mailing-List: linux-kernel@vger.kernel.org

On Thu, 30 Nov 2000, Pavel Machek wrote:

> Hi!
> 
> > > On Tue, 28 Nov 2000, Jan Rekorajski wrote:
> > > > --- linux/kernel/fork.c~	Tue Sep  5 23:48:59 2000
> > > > +++ linux/kernel/fork.c	Sun Nov 26 20:22:20 2000
> > > > @@ -560,7 +560,8 @@
> > > >  	*p = *current;
> > > >  
> > > >  	retval = -EAGAIN;
> > > > -	if (atomic_read(&p->user->processes) >= p->rlim[RLIMIT_NPROC].rlim_cur)
> > > > +	if (p->user->uid &&
> > > > +	   (atomic_read(&p->user->processes) >= p->rlim[RLIMIT_NPROC].rlim_cur))
> > > 
> > > Jan,
> > > 
> > > Hardcoding things signifying special treatment of uid=0 is almost always a
> > > bad idea. If you _really_ think that superuser (whatever entity that might
> > > be) should be exempt from RLIMIT_NPROC and can prove that (SuSv2 seems to
> > > be silent so you may be right), then you should use capable() to do proper
> > > capability test and not that horrible explicit uid test as in your patch
> > > above.
> > 
> > Ok, how about setting limits on login? When this looks like:
> > 
> > --- uid = 0 here
> > setrlimit(RLIMIT_NPROC, n)
> > fork()		<- this will fail if root has >n processes
> > setuid(user)
> > 
> > and it is hard to change this sequence, all PAM enabled apps depend
> > on it :(
> 
> So PAM dictates kernel changes? Fix pam, do not break kernel.

Fixed :)

Jan
-- 
Jan R?korajski            |  ALL SUSPECTS ARE GUILTY. PERIOD!
baggins<at>mimuw.edu.pl   |  OTHERWISE THEY WOULDN'T BE SUSPECTS, WOULD THEY?
BOFH, type MANIAC         |                   -- TROOPS by Kevin Rubio
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/