Subject: Re: [PATCH] [request for inclusion] Realtime LSM
From: Lee Revell <rlrevell@joe-job.com>
To: Matt Mackall <mpm@selenic.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>, Andreas Steinmetz <ast@domdv.de>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@osdl.org>, Ingo Molnar <mingo@elte.hu>,
       "Jack O'Quin" <joq@io.com>
In-Reply-To: <20050107011820.GC2995@waste.org>
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Date: Thu, 06 Jan 2005 21:36:30 -0500
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On Thu, 2005-01-06 at 17:18 -0800, Matt Mackall wrote:
> Why can't this be done with a simple SUID helper to promote given
> tasks to RT with sched_setschedule, doing essentially all the checks
> this LSM is doing? 
> 
> Objections of "because it requires dangerous root or suid" don't fly,
> an RT app under user control can DoS the box trivially. Never mind you
> need root to configure the LSM anyway..

Yes but a bug in an app running as root can trash the filesystem.  The
worst you can do with RT privileges is lock up the machine.

Lee

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