From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751283AbWDERC2 (ORCPT ); Wed, 5 Apr 2006 13:02:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751284AbWDERC2 (ORCPT ); Wed, 5 Apr 2006 13:02:28 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:50873 "EHLO ZenIV.linux.org.uk") by vger.kernel.org with ESMTP id S1751283AbWDERC1 (ORCPT ); Wed, 5 Apr 2006 13:02:27 -0400 Date: Wed, 5 Apr 2006 18:02:26 +0100 From: Al Viro To: Jon Smirl Cc: gregkh@suse.de, linux-kernel@vger.kernel.org, stable@kernel.org Subject: Re: [patch 03/26] sysfs: zero terminate sysfs write buffers (CVE-2006-1055) Message-ID: <20060405170226.GL27946@ftp.linux.org.uk> References: <20060404235634.696852000@quad.kroah.org> <20060404235947.GD27049@kroah.com> <20060405190928.17b9ba6a.vsu@altlinux.ru> <20060405152123.GH27946@ftp.linux.org.uk> <9e4733910604050934s46ec20fbr905f78832431d91d@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9e4733910604050934s46ec20fbr905f78832431d91d@mail.gmail.com> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 05, 2006 at 12:34:49PM -0400, Jon Smirl wrote: > On 4/5/06, Al Viro wrote: > > On Wed, Apr 05, 2006 at 07:09:28PM +0400, Sergey Vlasov wrote: > > > This will break the "color_map" sysfs file for framebuffers - > > > drivers/video/fbsysfs.c:store_cmap() expects to get exactly 4096 bytes > > > for a colormap with 256 entries. In fact, the original patch which > > > changed PAGE_SIZE - 1 to PAGE_SIZE: > > > > ... cheerfully assuming that nobody assumes NUL-termination and > > everyone (sysfs patch writers!) certainly uses the length argument. > > Fscking brilliant, that. > > Why does sysfs have two string length determination methods - both > NULL termination and a length parameter. It should be one or the > other, not both. Having both simply cause problems when some > developers implement one scheme and others only implement the other. Which part of "sysfs patches can be written by idiots and usually are" is too hard to understand? Oh, wait. I see... Well, nevermind, then...