Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751169Ab2BVFhd (ORCPT ); Wed, 22 Feb 2012 00:37:33 -0500 Received: from mx1.redhat.com ([209.132.183.28]:51921 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750735Ab2BVFhc (ORCPT ); Wed, 22 Feb 2012 00:37:32 -0500 Date: Wed, 22 Feb 2012 00:36:52 -0500 From: "'Dave Jones'" To: Jack Wang Cc: "'Tejun Heo'" , "'Jun'ichi Nomura'" , "'Jens Axboe'" , linux-kernel@vger.kernel.org, "'linux-scsi'" , "'Naveen Goswamy'" , "'James Bottomley'" , "'Stefan Richter'" , sgruszka@redhat.com, "'Huajun Li'" Subject: Re: [PATCH] Fix NULL pointer dereference in sd_revalidate_disk Message-ID: <20120222053651.GA7891@redhat.com> Mail-Followup-To: 'Dave Jones' , Jack Wang , 'Tejun Heo' , 'Jun'ichi Nomura' , 'Jens Axboe' , linux-kernel@vger.kernel.org, 'linux-scsi' , 'Naveen Goswamy' , 'James Bottomley' , 'Stefan Richter' , sgruszka@redhat.com, 'Huajun Li' References: <4F443E81.2060402@ce.jp.nec.com> <20120222010435.GI12236@google.com> <95E22EAF20104309BF3938E7820F36D6@usish.com.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <95E22EAF20104309BF3938E7820F36D6@usish.com.cn> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4001 Lines: 131 On Wed, Feb 22, 2012 at 12:58:08PM +0800, Jack Wang wrote: > Should this need pick up into stable too? > > Jack The 3.2 backport seems fairly trivial (just some stuff moved to different files) Here's the patch I did for Fedora. Dave --- linux/fs/partitions/check.c~ 2012-02-20 18:32:55.314253719 -0500 +++ linux/fs/partitions/check.c 2012-02-20 18:34:46.509859745 -0500 @@ -539,17 +539,11 @@ static bool disk_unlock_native_capacity( } } -int rescan_partitions(struct gendisk *disk, struct block_device *bdev) +static int drop_partitions(struct gendisk *disk, struct block_device *bdev) { - struct parsed_partitions *state = NULL; struct disk_part_iter piter; struct hd_struct *part; - int p, highest, res; -rescan: - if (state && !IS_ERR(state)) { - kfree(state); - state = NULL; - } + int res; if (bdev->bd_part_count) return -EBUSY; @@ -562,6 +556,24 @@ rescan: delete_partition(disk, part->partno); disk_part_iter_exit(&piter); + return 0; +} + +int rescan_partitions(struct gendisk *disk, struct block_device *bdev) +{ + struct parsed_partitions *state = NULL; + struct hd_struct *part; + int p, highest, res; +rescan: + if (state && !IS_ERR(state)) { + kfree(state); + state = NULL; + } + + res = drop_partitions(disk, bdev); + if (res) + return res; + if (disk->fops->revalidate_disk) disk->fops->revalidate_disk(disk); check_disk_size_change(disk, bdev); @@ -665,6 +677,26 @@ rescan: return 0; } +int invalidate_partitions(struct gendisk *disk, struct block_device *bdev) +{ + int res; + + if (!bdev->bd_invalidated) + return 0; + + res = drop_partitions(disk, bdev); + if (res) + return res; + + set_capacity(disk, 0); + check_disk_size_change(disk, bdev); + bdev->bd_invalidated = 0; + /* tell userspace that the media / partition table may have changed */ + kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); + + return 0; +} + unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p) { struct address_space *mapping = bdev->bd_inode->i_mapping; --- linux/include/linux/genhd.h~ 2012-02-20 18:35:02.777802107 -0500 +++ linux/include/linux/genhd.h 2012-02-20 18:35:13.873762792 -0500 @@ -596,6 +596,7 @@ extern char *disk_name (struct gendisk * extern int disk_expand_part_tbl(struct gendisk *disk, int target); extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev); +extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev); extern struct hd_struct * __must_check add_partition(struct gendisk *disk, int partno, sector_t start, sector_t len, int flags, --- linux/fs/block_dev.c~ 2012-02-20 18:35:24.890723757 -0500 +++ linux/fs/block_dev.c 2012-02-20 18:36:25.166510197 -0500 @@ -1159,8 +1159,12 @@ static int __blkdev_get(struct block_dev * The latter is necessary to prevent ghost * partitions on a removed medium. */ - if (bdev->bd_invalidated && (!ret || ret == -ENOMEDIUM)) - rescan_partitions(disk, bdev); + if (bdev->bd_invalidated) { + if (!ret) + rescan_partitions(disk, bdev); + else if (ret == -ENOMEDIUM) + invalidate_partitions(disk, bdev); + } if (ret) goto out_clear; } else { @@ -1190,8 +1194,12 @@ static int __blkdev_get(struct block_dev if (bdev->bd_disk->fops->open) ret = bdev->bd_disk->fops->open(bdev, mode); /* the same as first opener case, read comment there */ - if (bdev->bd_invalidated && (!ret || ret == -ENOMEDIUM)) - rescan_partitions(bdev->bd_disk, bdev); + if (bdev->bd_invalidated) { + if (!ret) + rescan_partitions(bdev->bd_disk, bdev); + else if (ret == -ENOMEDIUM) + invalidate_partitions(bdev->bd_disk, bdev); + } if (ret) goto out_unlock_bdev; } -- 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/