From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64A3CC6778A for ; Thu, 5 Jul 2018 13:10:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 074BD24137 for ; Thu, 5 Jul 2018 13:10:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 074BD24137 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754579AbeGENKH (ORCPT ); Thu, 5 Jul 2018 09:10:07 -0400 Received: from mga02.intel.com ([134.134.136.20]:33501 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754291AbeGENKF (ORCPT ); Thu, 5 Jul 2018 09:10:05 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Jul 2018 06:10:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,312,1526367600"; d="scan'208";a="69857964" Received: from kuha.fi.intel.com ([10.237.72.189]) by fmsmga001.fm.intel.com with SMTP; 05 Jul 2018 06:10:01 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Thu, 05 Jul 2018 16:10:01 +0300 Date: Thu, 5 Jul 2018 16:10:01 +0300 From: Heikki Krogerus To: Colin King Cc: Greg Kroah-Hartman , linux-usb@vger.kernel.org, kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH][next] usb: typec: fix dereference before null check on adev Message-ID: <20180705131001.GC15989@kuha.fi.intel.com> References: <20180704123406.9496-1-colin.king@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180704123406.9496-1-colin.king@canonical.com> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 04, 2018 at 01:34:06PM +0100, Colin King wrote: > From: Colin Ian King > > Pointer adev is being dereferenced before it is being sanity > checked with a null pointer check, hence it is possible for > a null pointer dereference to occur. Fix this by dereferencing > adev only once it is null checked. > > Detected by CoverityScan, CID#1471598 ("Dereference before null check") > > Fixes: 8a37d87d72f0 ("usb: typec: Bus type for alternate modes") > Signed-off-by: Colin Ian King Acked-by: Heikki Krogerus > --- > drivers/usb/typec/bus.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/typec/bus.c b/drivers/usb/typec/bus.c > index 999d7904172a..95a2b10127db 100644 > --- a/drivers/usb/typec/bus.c > +++ b/drivers/usb/typec/bus.c > @@ -51,7 +51,7 @@ static int typec_altmode_set_state(struct typec_altmode *adev, int state) > int typec_altmode_notify(struct typec_altmode *adev, > unsigned long conf, void *data) > { > - bool is_port = is_typec_port(adev->dev.parent); > + bool is_port; > struct altmode *altmode; > struct altmode *partner; > int ret; > @@ -64,6 +64,7 @@ int typec_altmode_notify(struct typec_altmode *adev, > if (!altmode->partner) > return -ENODEV; > > + is_port = is_typec_port(adev->dev.parent); > partner = altmode->partner; > > ret = typec_altmode_set_mux(is_port ? altmode : partner, (u8)conf); Thanks, -- heikki