From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id 0F07A6B006A for ; Sun, 31 May 2009 02:34:15 -0400 (EDT) Message-ID: <4A2223FE.3000309@cs.helsinki.fi> Date: Sun, 31 May 2009 09:30:22 +0300 From: Pekka Enberg MIME-Version: 1.0 Subject: Re: [patch 0/5] Support for sanitization flag in low-level page allocator References: <20090530082048.GM29711@oblivion.subreption.com> <20090530173428.GA20013@elte.hu> <20090530180333.GH6535@oblivion.subreption.com> <20090530182113.GA25237@elte.hu> <20090530184534.GJ6535@oblivion.subreption.com> <20090530190828.GA31199@elte.hu> <4A21999E.5050606@redhat.com> <84144f020905301353y2f8c232na4c5f9dfb740eec4@mail.gmail.com> <20090530213311.GM6535@oblivion.subreption.com> <20090531001318.093e3665@lxorguk.ukuu.org.uk> <20090530231813.GP6535@oblivion.subreption.com> In-Reply-To: <20090530231813.GP6535@oblivion.subreption.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: "Larry H." Cc: Alan Cox , Rik van Riel , Ingo Molnar , linux-kernel@vger.kernel.org, Linus Torvalds , linux-mm@kvack.org, Ingo Molnar , pageexec@freemail.hu, Linus Torvalds List-ID: Larry H. wrote: > OK, I'm going to squeeze some time and provide patches that perform the > same my original page bit ones did, but using kzfree. Behold code like > in the tty buffer management, which uses the page allocator directly for > allocations greater than PAGE_SIZE in length. That needs special > treatment, and is exactly the reason I've proposed unconditional > sanitization since the original patches were rejected. You might want to also do the patch Alan suggested for the security conscious people. That is, do a memset() in every page free and wrap that under CONFIG_SECURITY_PARANOIA or something. There's no reason the kzfree() patches and that can't co-exist. Pekka -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org