From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757883Ab0E0QVy (ORCPT ); Thu, 27 May 2010 12:21:54 -0400 Received: from mail-pw0-f46.google.com ([209.85.160.46]:42142 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755434Ab0E0QVw (ORCPT ); Thu, 27 May 2010 12:21:52 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:subject:date:user-agent:cc:references:in-reply-to :mime-version:content-type:content-transfer-encoding:message-id; b=b53KSmPvnfu/UiuXbXXJXaK3VlRCrBENsngtRU2OLjuY3HhyDt0jN9lrLgNq0B5nFr H7+2fbSkbQevGWgKOsqmP5mpwt65ZARwN2lFcsq+RXNol+iRycyZO0NPXt0Ie1QTdfU8 2fRmoU1wZI1HaO88vmiboavvszebXugqXgAC0= From: Dmitry Torokhov To: Julia Lawall Subject: Re: [PATCH 9/11] drivers/platform/x86: Eliminate a NULL pointer dereference Date: Thu, 27 May 2010 09:21:42 -0700 User-Agent: KMail/1.13.2 (Linux/2.6.32.12-115.fc12.x86_64; KDE/4.4.2; x86_64; ; ) Cc: Mattia Dongili , Matthew Garrett , platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org References: In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201005270921.43049.dmitry.torokhov@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 27 May 2010 05:37:00 am Julia Lawall wrote: > From: Julia Lawall > > Give different error messages if device_enum is NULL or if its type field > has the wrong value. > > A simplified version of the semantic match that finds this problem is as > follows: (http://coccinelle.lip6.fr/) > > // > @r exists@ > expression E,E1; > identifier f; > statement S1,S2,S3; > @@ > > if ((E == NULL && ...) || ...) > { > ... when != if (...) S1 else S2 > when != E = E1 > * E->f > ... when any > return ...; > } > else S3 > // > > Signed-off-by: Julia Lawall > > --- > This may be too much clutter for little benefit. Other, perhaps less > informative solutions are possible. Verbosity should be OK but I think that mixing pr_xxx() and naked printks in the same patch is not very nice. > > drivers/platform/x86/sony-laptop.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/platform/x86/sony-laptop.c > b/drivers/platform/x86/sony-laptop.c index 1387c5f..9db8d2b 100644 > --- a/drivers/platform/x86/sony-laptop.c > +++ b/drivers/platform/x86/sony-laptop.c > @@ -1196,8 +1196,12 @@ static void sony_nc_rfkill_setup(struct acpi_device > *device) } > > device_enum = (union acpi_object *) buffer.pointer; > - if (!device_enum || device_enum->type != ACPI_TYPE_BUFFER) { > - printk(KERN_ERR "Invalid SN06 return object 0x%.2x\n", > + if (!device_enum) { > + pr_err("Invalid SN06 return object\n"); > + goto out_no_enum; > + } > + if (device_enum->type != ACPI_TYPE_BUFFER) { > + printk(KERN_ERR "Invalid SN06 return object type 0x%.2x\n", > device_enum->type); > goto out_no_enum; > } Thanks. -- Dmitry