From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754578AbaEFXtn (ORCPT ); Tue, 6 May 2014 19:49:43 -0400 Received: from SpacedOut.fries.net ([67.64.210.234]:60883 "EHLO SpacedOut.fries.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751105AbaEFXtl (ORCPT ); Tue, 6 May 2014 19:49:41 -0400 Date: Tue, 6 May 2014 18:49:30 -0500 From: David Fries To: Alexey Khoroshilov Cc: Evgeniy Polyakov , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, ldv-project@linuxtesting.org Subject: Re: [PATCH v2] w1: do not unlock unheld list_mutex in __w1_remove_master_device() Message-ID: <20140506234930.GU21508@spacedout.fries.net> References: <20140501034759.GG5096@spacedout.fries.net> <1399411564-16172-1-git-send-email-khoroshilov@ispras.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1399411564-16172-1-git-send-email-khoroshilov@ispras.ru> User-Agent: Mutt/1.5.21 (2010-09-15) X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.3.9 (SpacedOut.fries.net [127.0.0.1]); Tue, 06 May 2014 18:49:31 -0500 (CDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Acked-by: David Fries On Wed, May 07, 2014 at 01:26:04AM +0400, Alexey Khoroshilov wrote: > w1_process_callbacks() expects to be called with dev->list_mutex held, > but it is the fact only in w1_process(). __w1_remove_master_device() > calls w1_process_callbacks() after it releases list_mutex. > > The patch fixes __w1_remove_master_device() to acquire list_mutex > for w1_process_callbacks(). > > Found by Linux Driver Verification project (linuxtesting.org). > > Signed-off-by: Alexey Khoroshilov > --- > drivers/w1/w1.c | 2 ++ > drivers/w1/w1_int.c | 4 ++++ > 2 files changed, 6 insertions(+) > > diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c > index ff52618cafbe..5d7341520544 100644 > --- a/drivers/w1/w1.c > +++ b/drivers/w1/w1.c > @@ -1078,6 +1078,8 @@ static void w1_search_process(struct w1_master *dev, u8 search_type) > * w1_process_callbacks() - execute each dev->async_list callback entry > * @dev: w1_master device > * > + * The w1 master list_mutex must be held. > + * > * Return: 1 if there were commands to executed 0 otherwise > */ > int w1_process_callbacks(struct w1_master *dev) > diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c > index 9b084db739c7..728039d2efe1 100644 > --- a/drivers/w1/w1_int.c > +++ b/drivers/w1/w1_int.c > @@ -219,9 +219,13 @@ void __w1_remove_master_device(struct w1_master *dev) > > if (msleep_interruptible(1000)) > flush_signals(current); > + mutex_lock(&dev->list_mutex); > w1_process_callbacks(dev); > + mutex_unlock(&dev->list_mutex); > } > + mutex_lock(&dev->list_mutex); > w1_process_callbacks(dev); > + mutex_unlock(&dev->list_mutex); > > memset(&msg, 0, sizeof(msg)); > msg.id.mst.id = dev->id; > -- > 1.8.3.2 -- David Fries PGP pub CB1EE8F0 http://fries.net/~david/