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Message-ID: <4592C038.8010407@madrabbit.org>
Date: Wed, 27 Dec 2006 10:49:28 -0800
From: Ray Lee <ray-lk@madrabbit.org>
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To: Rob Landley <rob@landley.net>
Cc: Vadim Lobanov <vlobanov@speakeasy.net>, ray-gmail@madrabbit.org,
       linux-kernel@vger.kernel.org,
       David McCullough <david_mccullough@au.securecomputing.com>
Subject: Re: Feature request: exec self for NOMMU.
References: <200612261823.07927.rob@landley.net> <200612270051.52690.rob@landley.net> <1167199716.5616.3.camel@localhost.localdomain> <200612270329.16320.rob@landley.net>
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Rob Landley wrote:
> On Wednesday 27 December 2006 1:08 am, Vadim Lobanov wrote:
>> On Wed, 2006-12-27 at 00:51 -0500, Rob Landley wrote:
>>> On Wednesday 27 December 2006 12:13 am, Ray Lee wrote:
>>>> How about openning an fd to yourself at the beginning of execution, then
>>>> calling fexecve later?
>>> I haven't got a man page for fexecve.  Does libc have it?
>> It's implemented inside glibc, and uses /proc to execve() the file that
>> the fd points to.

Oh, hmm. Then I think it won't work, will it? I'd assumed fexecve was
implemented in kernel.

> Cute, and I can do that.  Assuming /proc is mounted in the chroot 
> environment...

Maybe I'm just confused -- wouldn't be the first time -- but if it's
implemented inside userspace, then once you chroot() you won't be able
to execute the path you find via /proc, will you?