From patchwork Wed Jul 29 02:42:37 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Woithe X-Patchwork-Id: 38050 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n6T2hoCZ027128 for ; Wed, 29 Jul 2009 02:43:51 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756240AbZG2CnJ (ORCPT ); Tue, 28 Jul 2009 22:43:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756242AbZG2CnJ (ORCPT ); Tue, 28 Jul 2009 22:43:09 -0400 Received: from adelphi.physics.adelaide.edu.au ([129.127.102.1]:54586 "EHLO adelphi.physics.adelaide.edu.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756115AbZG2CnH (ORCPT ); Tue, 28 Jul 2009 22:43:07 -0400 Received: from mercury.physics.adelaide.edu.au (IDENT:0@mercury [129.127.102.44]) by adelphi.physics.adelaide.edu.au (8.13.7/8.13.7/UofA-Physics-1.0) with ESMTP id n6T2gbiD023978; Wed, 29 Jul 2009 12:12:37 +0930 Received: from mercury.physics.adelaide.edu.au (IDENT:7157@localhost [127.0.0.1]) by mercury.physics.adelaide.edu.au (8.13.4/8.13.4) with ESMTP id n6T2gbRN025489; Wed, 29 Jul 2009 12:12:37 +0930 Received: (from jwoithe@localhost) by mercury.physics.adelaide.edu.au (8.13.4/8.13.4/Submit) id n6T2gbP1025488; Wed, 29 Jul 2009 12:12:37 +0930 From: Jonathan Woithe Message-Id: <200907290242.n6T2gbP1025488@mercury.physics.adelaide.edu.au> Subject: Re: [PATCH 6/12] drivers/platform/x86: Correct redundant test To: julia@diku.dk (Julia Lawall) Date: Wed, 29 Jul 2009 12:12:37 +0930 (CST) Cc: jwoithe@physics.adelaide.edu.au (Jonathan Woithe), pmarques@grupopie.com (Paulo Marques), linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org In-Reply-To: from "Julia Lawall" at Jul 29, 2009 04:22:51 AM X-Mailer: ELM [version 2.5 PL6] MIME-Version: 1.0 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org Hi Julia > > > Julia Lawall wrote: > > > > [...] > > > > --- > > > > drivers/platform/x86/fujitsu-laptop.c | 3 --- > > > > 1 files changed, 0 insertions(+), 3 deletions(-) > > > > > > > > diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c > > > > index 218b9a1..5306901 100644 > > > > --- a/drivers/platform/x86/fujitsu-laptop.c > > > > +++ b/drivers/platform/x86/fujitsu-laptop.c > > > > @@ -745,9 +745,6 @@ static int acpi_fujitsu_remove(struct acpi_device *device, int type) > > > > > > > > fujitsu = acpi_driver_data(device); > > > > > > > > - if (!device || !acpi_driver_data(device)) > > > > - return -EINVAL; > > > > - > > > > > > Shouldn't this still do a: > > > > > > if (!fujitsu) > > > return -EINVAL; > > > > > > to avoid dereferencing a NULL pointer below? > > > > Hmm, yes it should. Well spotted. And I'm not certain how the duplicate > > test on "device" got in there in the first place. I suspect it came about > > due to some structural changes made a few versions ago and I failed to > > notice that the second check became redundant. > > If you are going to check fujitsu afterwards, then I think there is no > need to test the result of acpi_driver_data before. Yes, of course. I'll wake up soon, promise! So we're left with this. Signed-off-by: jwoithe@physics.adelaide.edu.au Regards jonathan --- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html --- a/drivers/platform/x86/fujitsu-laptop.c 2009-06-12 19:51:45.333234000 +0930 +++ b/drivers/platform/x86/fujitsu-laptop.c 2009-07-29 12:10:11.504901871 +0930 @@ -740,12 +740,12 @@ static int acpi_fujitsu_remove(struct ac { struct fujitsu_t *fujitsu = NULL; - if (!device || !acpi_driver_data(device)) + if (!device) return -EINVAL; fujitsu = acpi_driver_data(device); - if (!device || !acpi_driver_data(device)) + if (!fujitsu) return -EINVAL; fujitsu->acpi_handle = NULL;