From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756695AbZIPWSs (ORCPT ); Wed, 16 Sep 2009 18:18:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757540AbZIPWSl (ORCPT ); Wed, 16 Sep 2009 18:18:41 -0400 Received: from kroah.org ([198.145.64.141]:49800 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756978AbZIPWSd (ORCPT ); Wed, 16 Sep 2009 18:18:33 -0400 X-Mailbox-Line: From gregkh@mini.kroah.org Wed Sep 16 15:15:06 2009 Message-Id: <20090916221506.492585155@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Wed, 16 Sep 2009 15:13:26 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Tejun Heo , Jeff Garzik Subject: [patch 06/10] libata: fix off-by-one error in ata_tf_read_block() References: <20090916221320.283781925@mini.kroah.org> Content-Disposition: inline; filename=libata-fix-off-by-one-error-in-ata_tf_read_block.patch In-Reply-To: <20090916221529.GA28162@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Tejun Heo commit ac8672ea922bde59acf50eaa1eaa1640a6395fd2 upstream. ata_tf_read_block() has off-by-one error when converting CHS address to LBA. The bug isn't very visible because ata_tf_read_block() is used only when generating sense data for a failed RW command and CHS addressing isn't used too often these days. This problem was spotted by Atsushi Nemoto. Signed-off-by: Tejun Heo Reported-by: Atsushi Nemoto Signed-off-by: Jeff Garzik Signed-off-by: Greg Kroah-Hartman --- drivers/ata/libata-core.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -565,7 +565,13 @@ u64 ata_tf_read_block(struct ata_taskfil head = tf->device & 0xf; sect = tf->lbal; - block = (cyl * dev->heads + head) * dev->sectors + sect; + if (!sect) { + ata_dev_printk(dev, KERN_WARNING, "device reported " + "invalid CHS sector 0\n"); + sect = 1; /* oh well */ + } + + block = (cyl * dev->heads + head) * dev->sectors + sect - 1; } return block;