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Date: Sat, 13 Oct 2001 15:50:05 -0700
From: Aaron Lehmann <aaronl@vitelus.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Jamie Lokier <lk@tantalophile.demon.co.uk>, linux-kernel@vger.kernel.org
Subject: Re: Security question: "Text file busy" overwriting executables but not shared libraries?
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On Sat, Oct 13, 2001 at 04:27:48PM -0600, Eric W. Biederman wrote:
> > But it does have the advantage of allowing the sharing of memory, does
> > it not?
> 
> Only if you are going to write to the data.

Why? If gcc and another application read the source file with an
mmap() with the right parameters (read-only), it would only be shared
between them, as I understand it. If they both read() the file into
private buffers those can not be shared.
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