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Date: Wed, 23 May 2007 17:55:35 -0700
From: Julian Elischer <julian@elischer.org>
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To: Colin Percival <cperciva@freebsd.org>
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Cc: Poul-Henning Kamp <phk@phk.freebsd.dk>,
	"freebsd-arch@freebsd.org" <freebsd-arch@freebsd.org>
Subject: Re: RFC: Removing file(1)+libmagic(3) from the base system
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Colin Percival wrote:
> Poul-Henning Kamp wrote:
>> In message <46546E16.9070707@freebsd.org>, Colin Percival writes:
>>> I'd like to remove file(1) and libmagic(3) from the FreeBSD base system
>>> for the following reasons:
>> One mitigating option would be to open the magic file and input
>> and sequester the file process in a jail.
> 
> Last time I checked, unprivileged processes couldn't jail themselves.  We
> could make file(1) setuid root and use a privilege separation approach,
> but I'm not convinced that would be a net win.

How about a bit in the headers of a program that are set by the Makefile.
If the bit is not set then the elf program executor sets a bit that
forbids exec from ever running..

how many programs actually need to be able to run exec..
the average exploit does an exec(/bin/sh)


> 
> Colin Percival
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