Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754045AbYKDEQa (ORCPT ); Mon, 3 Nov 2008 23:16:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751160AbYKDEQU (ORCPT ); Mon, 3 Nov 2008 23:16:20 -0500 Received: from hera.kernel.org ([140.211.167.34]:47682 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751112AbYKDEQT (ORCPT ); Mon, 3 Nov 2008 23:16:19 -0500 Message-ID: <490FCC87.1070205@kernel.org> Date: Tue, 04 Nov 2008 13:16:07 +0900 From: Tejun Heo User-Agent: Thunderbird 2.0.0.12 (X11/20071114) MIME-Version: 1.0 To: petkovbb@gmail.com CC: axboe@kernel.dk, bzolnier@gmail.com, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Subject: [PATCH] block: fix __blkdev_get() for removable devices References: <20081029071319.GA9205@gollum.tnic> <20081101201419.GA29462@gollum.tnic> <490F1AC6.8000109@kernel.org> <9ea470500811030956k209b2f2ci10bcde1ea4ac7334@mail.gmail.com> In-Reply-To: <9ea470500811030956k209b2f2ci10bcde1ea4ac7334@mail.gmail.com> X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.0 (hera.kernel.org [127.0.0.1]); Tue, 04 Nov 2008 04:16:15 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3333 Lines: 106 Commit 0762b8bde9729f10f8e6249809660ff2ec3ad735 moved disk_get_part() in front of recursive get on the whole disk, which caused removable devices to try disk_get_part() before rescanning after a new media is inserted, which might fail legit open attempts or give the old partition. This patch fixes the problem by moving disk_get_part() after __blkdev_get() on the whole disk. This problem was spotted by Borislav Petkov. Signed-off-by: Tejun Heo Cc: petkovbb@googlemail.com --- Borislav, can you please verify this patch? Thanks. fs/block_dev.c | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-) diff --git a/fs/block_dev.c b/fs/block_dev.c index 88a776f..db831ef 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -986,7 +986,6 @@ static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part); static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) { struct gendisk *disk; - struct hd_struct *part = NULL; int ret; int partno; int perm = 0; @@ -1004,24 +1003,25 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) return ret; } - ret = -ENXIO; - lock_kernel(); + ret = -ENXIO; disk = get_gendisk(bdev->bd_dev, &partno); if (!disk) goto out_unlock_kernel; - part = disk_get_part(disk, partno); - if (!part) - goto out_unlock_kernel; mutex_lock_nested(&bdev->bd_mutex, for_part); if (!bdev->bd_openers) { bdev->bd_disk = disk; - bdev->bd_part = part; bdev->bd_contains = bdev; if (!partno) { struct backing_dev_info *bdi; + + ret = -ENXIO; + bdev->bd_part = disk_get_part(disk, partno); + if (!bdev->bd_part) + goto out_clear; + if (disk->fops->open) { ret = disk->fops->open(bdev, mode); if (ret) @@ -1049,18 +1049,17 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) bdev->bd_contains = whole; bdev->bd_inode->i_data.backing_dev_info = whole->bd_inode->i_data.backing_dev_info; + bdev->bd_part = disk_get_part(disk, partno); if (!(disk->flags & GENHD_FL_UP) || - !part || !part->nr_sects) { + !bdev->bd_part || !bdev->bd_part->nr_sects) { ret = -ENXIO; goto out_clear; } - bd_set_size(bdev, (loff_t)part->nr_sects << 9); + bd_set_size(bdev, (loff_t)bdev->bd_part->nr_sects << 9); } } else { - disk_put_part(part); put_disk(disk); module_put(disk->fops->owner); - part = NULL; disk = NULL; if (bdev->bd_contains == bdev) { if (bdev->bd_disk->fops->open) { @@ -1080,6 +1079,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) return 0; out_clear: + disk_put_part(bdev->bd_part); bdev->bd_disk = NULL; bdev->bd_part = NULL; bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info; @@ -1091,7 +1091,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) out_unlock_kernel: unlock_kernel(); - disk_put_part(part); if (disk) module_put(disk->fops->owner); put_disk(disk); -- 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/