From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763969AbYHDU0v (ORCPT ); Mon, 4 Aug 2008 16:26:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763858AbYHDU0d (ORCPT ); Mon, 4 Aug 2008 16:26:33 -0400 Received: from cantor.suse.de ([195.135.220.2]:48933 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1763844AbYHDU0c (ORCPT ); Mon, 4 Aug 2008 16:26:32 -0400 Date: Mon, 4 Aug 2008 13:15:51 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Frank Seidel , Andreas Dilger , OGAWA Hirofumi Subject: [patch 17/33] fat: detect media without partition table correctly Message-ID: <20080804201551.GR1139@suse.de> References: <20080804200515.110033151@mini.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="fat-detect-media-without-partition-table-correctly.patch" In-Reply-To: <20080804201321.GA1139@suse.de> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.25-stable review patch. If anyone has any objections, please let us know. ------------------ From: Frank Seidel commit 0607fd02587a6b4b086dc746d63123c1f284db68 upstream I received a complaint that some FAT formated medias (e.g. sd memory cards) trigger a "unknown partition table" message even though there is no partition table and they work correctly, while in general (when e.g. formated with mkdosfs or even Windows Vista) this message is not shown. Currently this seems only to happen when the medias get formatted with Windows XP (and possibly Win 2000). Then the boot indicator byte contains garbage (part of text message) and so do the other parts checked by msdos_paritition which then later triggers this message. References: novell bug #364365 Most fat formatted media without partition table contains zeros in the boot indication and the other tested bytes and so falls through the checks in msdos_partition, leading it to return with 1 (all is fine). But some (e.g. WinXP formatted) fat fomated medias don't use boot_ind and so the check fails and causes a "unkown partition table" warning eventhough there is none and everything would be fine. This additional check directly verifies if there is a fat formatted medium without a partition table. Signed-off-by: Frank Seidel Cc: Andreas Dilger Acked-by: OGAWA Hirofumi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/partitions/msdos.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) --- a/fs/partitions/msdos.c +++ b/fs/partitions/msdos.c @@ -18,7 +18,7 @@ * * Re-organised Feb 1998 Russell King */ - +#include #include "check.h" #include "msdos.h" @@ -419,6 +419,7 @@ int msdos_partition(struct parsed_partit Sector sect; unsigned char *data; struct partition *p; + struct fat_boot_sector *fb; int slot; data = read_dev_sector(bdev, 0, §); @@ -444,8 +445,21 @@ int msdos_partition(struct parsed_partit p = (struct partition *) (data + 0x1be); for (slot = 1; slot <= 4; slot++, p++) { if (p->boot_ind != 0 && p->boot_ind != 0x80) { - put_dev_sector(sect); - return 0; + /* + * Even without a valid boot inidicator value + * its still possible this is valid FAT filesystem + * without a partition table. + */ + fb = (struct fat_boot_sector *) data; + if (slot == 1 && fb->reserved && fb->fats + && fat_valid_media(fb->media)) { + printk("\n"); + put_dev_sector(sect); + return 1; + } else { + put_dev_sector(sect); + return 0; + } } } --