Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759231AbYJINBX (ORCPT ); Thu, 9 Oct 2008 09:01:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758019AbYJINBN (ORCPT ); Thu, 9 Oct 2008 09:01:13 -0400 Received: from turing-police.cc.vt.edu ([128.173.14.107]:41353 "EHLO turing-police.cc.vt.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757436AbYJINBN (ORCPT ); Thu, 9 Oct 2008 09:01:13 -0400 X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.2 To: Pavel Machek Cc: Matthew Wilcox , Nick Piggin , Peter Zijlstra , torvalds@linux-foundation.org, Andrew Morton , Andi Kleen , Hisashi Hifumi , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, "Aneesh Kumar K.V" , "Theodore Ts'o" Subject: Re: [RESEND] [PATCH] VFS: make file->f_pos access atomic on 32bit arch In-Reply-To: Your message of "Thu, 09 Oct 2008 14:23:19 +0200." <20081009122319.GC1623@ucw.cz> From: Valdis.Kletnieks@vt.edu References: <6.0.0.20.2.20081007140438.0580f110@172.19.0.2> <20081007105056.16d9e785.akpm@linux-foundation.org> <1223405963.26330.83.camel@lappy.programming.kicks-ass.net> <200810081335.44576.nickpiggin@yahoo.com.au> <20081008025209.GO25780@parisc-linux.org> <20081009122319.GC1623@ucw.cz> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1223556574_7177P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Thu, 09 Oct 2008 08:49:35 -0400 Message-ID: <52983.1223556575@turing-police.cc.vt.edu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1078 Lines: 32 --==_Exmh_1223556574_7177P Content-Type: text/plain; charset=us-ascii On Thu, 09 Oct 2008 14:23:19 +0200, Pavel Machek said: > We have append-only files, and normal users should not be able to work > around that restriction. Can you give an example of two *plausible* starting offsets, and 2 write lengths, which when subjected to this race manage to override the append-only attribute? I believe somebody already checked the code, and for append-only we force the offset in the kernel for *each* write. --==_Exmh_1223556574_7177P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Exmh version 2.5 07/13/2001 iD8DBQFI7f3ecC3lWbTT17ARAiRdAJ9x0IisngS+YWbT5aoCoZ9zQsOZGwCdGV5b svTuBKuLM49zwoQGHq0rEKo= =W/qm -----END PGP SIGNATURE----- --==_Exmh_1223556574_7177P-- -- 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/