From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757806Ab2HJRZh (ORCPT ); Fri, 10 Aug 2012 13:25:37 -0400 Received: from mx1.redhat.com ([209.132.183.28]:9247 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754658Ab2HJRZf (ORCPT ); Fri, 10 Aug 2012 13:25:35 -0400 Date: Fri, 10 Aug 2012 13:25:24 -0400 From: Vivek Goyal To: Herton Ronaldo Krzesinski Cc: Jiri Kosina , Andrew Morton , Jens Axboe , Tejun Heo , linux-kernel@vger.kernel.org, Ben Hutchings Subject: Re: [PATCH 3/6] floppy: avoid leaking extra reference to queue on do_floppy_init error handling Message-ID: <20120810172524.GH5416@redhat.com> References: <1344542391-16474-1-git-send-email-herton.krzesinski@canonical.com> <1344542391-16474-4-git-send-email-herton.krzesinski@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1344542391-16474-4-git-send-email-herton.krzesinski@canonical.com> 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 On Thu, Aug 09, 2012 at 04:59:48PM -0300, Herton Ronaldo Krzesinski wrote: > After commit 3f9a5aa ("floppy: Cleanup disk->queue before caling > put_disk() if add_disk() was never called"), if something fails in the > add_disk loop, we unconditionally set disks[dr]->queue to NULL. But > that's wrong, since we may have succesfully done an add_disk on some of > the drives previously in the loop, and in this case we would end up with > an extra reference to the disks[dr]->queue. > > Add a new global array to mark "registered" disks, and use that to check > if we did an add_disk on one of the disks already. Using an array to > track added disks also will help to simplify/cleanup code later, as > suggested by Vivek Goyal. > > Signed-off-by: Herton Ronaldo Krzesinski > Cc: stable@vger.kernel.org Looks good to me. Acked-by: Vivek Goyal Vivek > --- > drivers/block/floppy.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c > index 1e09e99..9272203 100644 > --- a/drivers/block/floppy.c > +++ b/drivers/block/floppy.c > @@ -409,6 +409,7 @@ static struct floppy_drive_struct drive_state[N_DRIVE]; > static struct floppy_write_errors write_errors[N_DRIVE]; > static struct timer_list motor_off_timer[N_DRIVE]; > static struct gendisk *disks[N_DRIVE]; > +static bool disk_registered[N_DRIVE]; > static struct block_device *opened_bdev[N_DRIVE]; > static DEFINE_MUTEX(open_lock); > static struct floppy_raw_cmd *raw_cmd, default_raw_cmd; > @@ -4305,6 +4306,7 @@ static int __init do_floppy_init(void) > disks[drive]->flags |= GENHD_FL_REMOVABLE; > disks[drive]->driverfs_dev = &floppy_device[drive].dev; > add_disk(disks[drive]); > + disk_registered[drive] = true; > } > > return 0; > @@ -4328,7 +4330,8 @@ out_put_disk: > * put_disk() is not paired with add_disk() and > * will put queue reference one extra time. fix it. > */ > - disks[dr]->queue = NULL; > + if (!disk_registered[dr]) > + disks[dr]->queue = NULL; > } > put_disk(disks[dr]); > } > -- > 1.7.9.5