Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751647AbXANTka (ORCPT ); Sun, 14 Jan 2007 14:40:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751648AbXANTka (ORCPT ); Sun, 14 Jan 2007 14:40:30 -0500 Received: from moutng.kundenserver.de ([212.227.126.179]:55157 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751646AbXANTk3 (ORCPT ); Sun, 14 Jan 2007 14:40:29 -0500 From: Bodo Eggert <7eggert@gmx.de> Subject: Re: O_DIRECT question To: Bill Davidsen , Michael Tokarev , Chris Mason , dean gaudet , Viktor , Aubrey , Hua Zhong , Hugh Dickins , linux-kernel@vger.kernel.org, hch@infradead.org, kenneth.w.chen@intel.com, akpm@osdl.org Reply-To: 7eggert@gmx.de Date: Sun, 14 Jan 2007 20:39:50 +0100 References: <7BYkO-5OV-17@gated-at.bofh.it> <7BYul-6gz-5@gated-at.bofh.it> <7C74B-2A4-23@gated-at.bofh.it> <7CaYA-mT-19@gated-at.bofh.it> <7Cpuz-64X-1@gated-at.bofh.it> <7Cz0T-4PH-17@gated-at.bofh.it> <7CBcl-86B-9@gated-at.bofh.it> <7CBvH-52-9@gated-at.bofh.it> <7CBFn-hw-1@gated-at.bofh.it> <7CBP1-KI-3@gated-at.bofh.it> <7CBYG-WK-3@gated-at.bofh.it> <7CXmz-88G-29@gated-at.bofh.it> <7CXFR-8vZ-15@gated-at.bofh.it> <7DfMP-2ak-19@gated-at.bofh.it> User-Agent: KNode/0.7.2 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7Bit Message-Id: X-be10.7eggert.dyndns.org-MailScanner-Information: See www.mailscanner.info for information X-be10.7eggert.dyndns.org-MailScanner: Found to be clean X-be10.7eggert.dyndns.org-MailScanner-From: 7eggert@gmx.de X-Provags-ID: kundenserver.de abuse@kundenserver.de login:9b3b2cc444a07783f194c895a09f1de9 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 663 Lines: 9 Bill Davidsen wrote: > My point is, that there is code to handle sparse data now, without > O_DIRECT involved, and if O_DIRECT bypasses that, it's not a problem > with the idea of O_DIRECT, the kernel has a security problem. The idea of O_DIRECT is to bypass the pagecache, and the pagecache is what provides the security against reading someone else's data using sparse files or partial-block-IO. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/