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Date: Thu, 4 Oct 2001 01:44:57 -0400 (EDT)
From: Alexander Viro <viro@math.psu.edu>
To: Linus Torvalds <torvalds@transmeta.com>
cc: linux-kernel@vger.kernel.org
Subject: Re: Security question: "Text file busy" overwriting executables but
 not shared libraries?
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On Thu, 4 Oct 2001, Linus Torvalds wrote:

> The reason the kernel refuses to honour it, is that MAP_DENYWRITE is an
> excellent DoS-vehicle - you just mmap("/etc/passwd") with MAP_DENYWRITE,
> and even root cannot write to it.. Vary nasty.

<nit>
I _really_ doubt that something does write() on /etc/passwd.  Create a
file and rename it over the thing - sure, but that's it.
</nit>

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