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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 B71A6ECE562 for ; Wed, 19 Sep 2018 07:45:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 62322214DA for ; Wed, 19 Sep 2018 07:45:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 62322214DA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=microchip.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 S1730802AbeISNVj (ORCPT ); Wed, 19 Sep 2018 09:21:39 -0400 Received: from esa2.microchip.iphmx.com ([68.232.149.84]:6468 "EHLO esa2.microchip.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727056AbeISNVj (ORCPT ); Wed, 19 Sep 2018 09:21:39 -0400 X-IronPort-AV: E=Sophos;i="5.53,393,1531810800"; d="scan'208";a="20143902" Received: from smtpout.microchip.com (HELO email.microchip.com) ([198.175.253.82]) by esa2.microchip.iphmx.com with ESMTP/TLS/DHE-RSA-AES256-SHA; 19 Sep 2018 00:44:58 -0700 Received: from localhost.localdomain (10.10.76.4) by chn-sv-exch05.mchp-main.com (10.10.76.106) with Microsoft SMTP Server id 14.3.352.0; Wed, 19 Sep 2018 00:44:57 -0700 Subject: Re: [PATCH v2] mtd: rawnand: atmel: Fix potential NULL pointer dereference To: "Gustavo A. R. Silva" , Boris Brezillon , Miquel Raynal , Richard Weinberger , David Woodhouse , Brian Norris , Marek Vasut , Nicolas Ferre , Alexandre Belloni , Ludovic Desroches CC: , , References: <20180918135555.GA18114@embeddedor.com> From: Tudor Ambarus Message-ID: <61472393-b699-45b4-6d74-cfa774669ad2@microchip.com> Date: Wed, 19 Sep 2018 10:44:54 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <20180918135555.GA18114@embeddedor.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/18/2018 04:55 PM, Gustavo A. R. Silva wrote: > There is a potential execution path in which function > of_find_compatible_node() returns NULL. In such a case, > we end up having a NULL pointer dereference when accessing > pointer *nfc_np* in function of_clk_get(). > > So, we better don't take any chances and fix this by null > checking pointer *nfc_np* before calling of_clk_get(). > > Addresses-Coverity-ID: 1473052 ("Dereference null return value") > Fixes: f88fc122cc34 ("mtd: nand: Cleanup/rework the atmel_nand driver") > Signed-off-by: Gustavo A. R. Silva Acked-by: Tudor Ambarus > --- > Changes in v2: > - Add Fixes tag to the commit log. > - Remove blank line before null checking nfc_np. > > drivers/mtd/nand/raw/atmel/nand-controller.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/mtd/nand/raw/atmel/nand-controller.c b/drivers/mtd/nand/raw/atmel/nand-controller.c > index a38633a..5bfbe97 100644 > --- a/drivers/mtd/nand/raw/atmel/nand-controller.c > +++ b/drivers/mtd/nand/raw/atmel/nand-controller.c > @@ -2034,6 +2034,10 @@ atmel_hsmc_nand_controller_legacy_init(struct atmel_hsmc_nand_controller *nc) > nand_np = dev->of_node; > nfc_np = of_find_compatible_node(dev->of_node, NULL, > "atmel,sama5d3-nfc"); > + if (!nfc_np) { > + dev_err(dev, "Could not find device node for sama5d3-nfc\n"); > + return -ENODEV; > + } > > nc->clk = of_clk_get(nfc_np, 0); > if (IS_ERR(nc->clk)) { >