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 DC488ECDE5F for ; Mon, 23 Jul 2018 11:59:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 84A8020880 for ; Mon, 23 Jul 2018 11:59:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 84A8020880 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=hofr.at 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 S2387954AbeGWNAE (ORCPT ); Mon, 23 Jul 2018 09:00:04 -0400 Received: from 178.115.242.59.static.drei.at ([178.115.242.59]:50246 "EHLO mail.osadl.at" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S2387847AbeGWNAD (ORCPT ); Mon, 23 Jul 2018 09:00:03 -0400 Received: by mail.osadl.at (Postfix, from userid 1001) id 2569D5C097D; Mon, 23 Jul 2018 11:57:33 +0000 (UTC) Date: Mon, 23 Jul 2018 11:57:33 +0000 From: Nicholas Mc Guire To: Marc Kleine-Budde Cc: Fabio Estevam , Nicholas Mc Guire , Wolfram Sang , Wolfgang Grandegger , "David S. Miller" , linux-can@vger.kernel.org, netdev , linux-kernel Subject: Re: [PATCH] can: mpc5xxx_can: check of_iomap return before use Message-ID: <20180723115733.GA6529@osadl.at> References: <1531163800-12111-1-git-send-email-hofrat@osadl.org> <4f81e688-3d5c-6174-5a76-f416ced63cf3@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4f81e688-3d5c-6174-5a76-f416ced63cf3@pengutronix.de> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 23, 2018 at 01:37:05PM +0200, Marc Kleine-Budde wrote: > On 07/09/2018 09:28 PM, Fabio Estevam wrote: > > On Mon, Jul 9, 2018 at 4:16 PM, Nicholas Mc Guire wrote: > >> of_iompa() can return NULL so that return needs to be checked and NULL > > > > s/of_iompa/of_iomap/ > > > >> treated as failure. While at it also take care of the missing > >> of_node_put() in the error path. > >> > >> Signed-off-by: Nicholas Mc Guire > >> Fixes: commit afa17a500a36 ("net/can: add driver for mscan family & mpc52xx_mscan") > >> --- > >> > >> Problem was found by an experimental coccinelle script > >> > >> Patch was compiletested with: mpc5200_defconfig + CONFIG_CAN=y, > >> CONFIG_CAN_MSCAN=y, CONFIG_CAN_MPC5XXX=y > >> (with a number of sparse warnings not related to the proposed change) > >> > >> Patch is against 4.18-rc3 (localversion-next is next-20180706) > >> > >> drivers/net/can/mscan/mpc5xxx_can.c | 5 +++++ > >> 1 file changed, 5 insertions(+) > >> > >> diff --git a/drivers/net/can/mscan/mpc5xxx_can.c b/drivers/net/can/mscan/mpc5xxx_can.c > >> index c7427bd..2949a38 100644 > >> --- a/drivers/net/can/mscan/mpc5xxx_can.c > >> +++ b/drivers/net/can/mscan/mpc5xxx_can.c > >> @@ -86,6 +86,11 @@ static u32 mpc52xx_can_get_clock(struct platform_device *ofdev, > >> return 0; > >> } > >> cdm = of_iomap(np_cdm, 0); > >> + if (!cdm) { > >> + of_node_put(np_cdm); > >> + dev_err(&ofdev->dev, "can't map clock node!\n"); > >> + return 0; > > > > I think you should return an error code here. -ENOMEM maybe? > > Can you send an updated version? > The way I understand the code the return value will be used as a frequency - the only valid error valeu thus is 0 here, so I think the return 0 is correct. thx! hofrat