From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [BUG] ati_remote2.c: possible mutex_lock without mutex_unlock Date: Wed, 14 Oct 2009 00:14:28 -0700 Message-ID: <20091014071428.GA5318@core.coreip.homeip.net> References: <1255456327.22233.0@pamir> <20091014062902.GA2971@core.coreip.homeip.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pz0-f188.google.com ([209.85.222.188]:58349 "EHLO mail-pz0-f188.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755572AbZJNHPI (ORCPT ); Wed, 14 Oct 2009 03:15:08 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Jiri Kosina Cc: iceberg , Vojtech Pavlik , Linux Kernlel Mailing List , linux-input@vger.kernel.org On Wed, Oct 14, 2009 at 09:11:06AM +0200, Jiri Kosina wrote: > On Tue, 13 Oct 2009, Dmitry Torokhov wrote: > > > Umm, I don't like assuming that EAGAIN can only mean that > > mutex_lock_interruptible() failed, seq_file core may theoretically > > return -EAGAIN too. In fact, looking through seq_file.c traverse() does > > return -EAGAIN in certain cases... > > Damn, you are right -- I explicitly checked for this, but have completely > overlooked the "Eoveflow:" branch in traverse(), which returns EAGAIN. So > my previous patch is of course incorrect. > > > Input: fix locking issue in /proc/bus/input/ handlers > > > > From: Dmitry Torokhov > > > > input_devices_seq_start() uses mutex_lock_interruptible() to acquire > > the input_mutex, but doesn't properly handle the situation when the > > call fails (for example due to interrupt). Instead of returning NULL > > (which indicates that there is no more data) we should return > > ERR_PTR()-encoded error. > > > > We also need explicit flag indicating whether input_mutex was acquired > > since input_devices_seq_stop() is called whether input_devices_seq_start() > > was successful or not. > > > > The same applies to input_handlers_seq_start(). > > > > Reported-by: iceberg > > Signed-off-by: Dmitry Torokhov > > Yup, looks OK to me. > Putting you as "Reviewed-by.." then, OK? -- Dmitry