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Date: Sat, 30 May 2009 19:04:43 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
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To: "Larry H." <research@subreption.com>
cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
       Rik van Riel <riel@redhat.com>, Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: [PATCH] Use kzfree in tty buffer management to enforce data
 sanitization
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On Sat, 30 May 2009, Larry H. wrote:
>
> This patch doesn't affect fastpaths.

This patch is ugly as hell.

You already know the size of the data to clear.

If we actually wanted this (and I am in _no_way_ saying we do), the only 
sane thing to do is to just do

	memset(buf->data, 0, N_TTY_BUF_SIZE);
	if (PAGE_SIZE != N_TTY_BUF_SIZE)
		kfree(...)
	else
		free_page(...)


but quite frankly, I'm not convinced about these patches at all.

I'm also not in the least convinced about how you just dismiss everybodys 
concerns.

		Linus