From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 9 Jan 2002 03:25:18 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 9 Jan 2002 03:25:09 -0500 Received: from 89dyn48.com21.casema.net ([62.234.20.48]:52705 "EHLO abraracourcix.bitwizard.nl") by vger.kernel.org with ESMTP id ; Wed, 9 Jan 2002 03:25:00 -0500 Message-Id: <200201090824.JAA25149@cave.bitwizard.nl> Subject: Re: lseek() on an iso9660 file In-Reply-To: from "H. Peter Anvin" at "Jan 7, 2002 09:48:35 am" To: "H. Peter Anvin" Date: Wed, 9 Jan 2002 09:24:56 +0100 (MET) CC: linux-kernel@vger.kernel.org From: R.E.Wolff@BitWizard.nl (Rogier Wolff) X-Mailer: ELM [version 2.4ME+ PL60 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org H. Peter Anvin wrote: > Followup to: > By author: "Richard B. Johnson" > In newsgroup: linux.dev.kernel > > > > Using Linux 2.4.1 I discovered a problem with lseek on CDROM files > > (iso9660). I just installed 2.4.17 and found the same problem. > > > > The problem: > > > > (1) A portion of the file, existing on a CDROM, is read and its the > > contents are written to an output file on writable media. > > > > (2) The current input file-position is obtained using > > pos = lseek(fd, 0, SEEK_CUR); The value returned is exactly > > the expected value. > > > > (3) The rest of the CDROM file is read and written to the output file. > > > > (4) The file-position of the CDROM file is then set back to the saved > > position using lseek(fd, pos, SEEK_SET); The value returned is > > exactly the expected value. > > > > (5) The CDROM file is then read and its contents are observed to be > > scrambled in some strange manner in which word-length groups of > > bytes from near the end of the file are interleaved with the > > correct bytes. Basically, the file ends up being about twice > > as long as the original, with every-other two-byte interval > > being filled with bytes from near the end of the file. > > > > a) How long is the file? > b) What is the offset? > c) What particular iso9660 options (RockRidge, Joliet, zisofs...) > does your disk use? > d) Mount options? > > This seems to be a rather serious bug, so I'd like to get to the > bottom with it. My questions would be: "What hardware?". Roger. -- ** R.E.Wolff@BitWizard.nl ** http://www.BitWizard.nl/ ** +31-15-2137555 ** *-- BitWizard writes Linux device drivers for any device you may have! --* * There are old pilots, and there are bold pilots. * There are also old, bald pilots.