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 B06D6C3279B for ; Fri, 6 Jul 2018 07:10:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5809023FDF for ; Fri, 6 Jul 2018 07:10:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5809023FDF 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 S1753586AbeGFHKm (ORCPT ); Fri, 6 Jul 2018 03:10:42 -0400 Received: from mga01.intel.com ([192.55.52.88]:2702 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753096AbeGFHKk (ORCPT ); Fri, 6 Jul 2018 03:10:40 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 06 Jul 2018 00:10:40 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,315,1526367600"; d="scan'208";a="70094456" Received: from kuha.fi.intel.com ([10.237.72.189]) by fmsmga001.fm.intel.com with SMTP; 06 Jul 2018 00:10:37 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Fri, 06 Jul 2018 10:10:36 +0300 Date: Fri, 6 Jul 2018 10:10:36 +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][V2] usb: typec: unlock dp->lock on error exit path, and also zero ret if successful Message-ID: <20180706071036.GB8308@kuha.fi.intel.com> References: <20180705133647.13016-1-colin.king@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180705133647.13016-1-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 Thu, Jul 05, 2018 at 02:36:47PM +0100, Colin King wrote: > From: Colin Ian King > > One of the error handling paths forgets to unlock dp->lock on the error > exit path leading to a potential lock-up. Also the return path for a > successful call to the function configuration_store can return an > uninitialized error return code if dp->alt->active is false, so ensure > ret is zeroed on the successful exit path to avoid garbage being returned. > > Detected by CoverityScan, CID#1471597 ("Unitialized scalar variable") > > Fixes: 0e3bb7d6894d ("usb: typec: Add driver for DisplayPort alternate mode") > Signed-off-by: Colin Ian King Acked-by: Heikki Krogerus > --- > > V2: move the ret = 0 assignment to the declaration > > --- > drivers/usb/typec/altmodes/displayport.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c > index ef12b15bd484..3f06e94771a7 100644 > --- a/drivers/usb/typec/altmodes/displayport.c > +++ b/drivers/usb/typec/altmodes/displayport.c > @@ -333,7 +333,7 @@ configuration_store(struct device *dev, struct device_attribute *attr, > u32 conf; > u32 cap; > int con; > - int ret; > + int ret = 0; > > con = sysfs_match_string(configurations, buf); > if (con < 0) > @@ -349,8 +349,10 @@ configuration_store(struct device *dev, struct device_attribute *attr, > cap = DP_CAP_CAPABILITY(dp->alt->vdo); > > if ((con == DP_CONF_DFP_D && !(cap & DP_CAP_DFP_D)) || > - (con == DP_CONF_UFP_D && !(cap & DP_CAP_UFP_D))) > - return -EINVAL; > + (con == DP_CONF_UFP_D && !(cap & DP_CAP_UFP_D))) { > + ret = -EINVAL; > + goto err_unlock; > + } > > conf = dp->data.conf & ~DP_CONF_DUAL_D; > conf |= con; Thanks, -- heikki