From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751148AbdEaMLe (ORCPT ); Wed, 31 May 2017 08:11:34 -0400 Received: from mga03.intel.com ([134.134.136.65]:5270 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751022AbdEaMLd (ORCPT ); Wed, 31 May 2017 08:11:33 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.38,423,1491289200"; d="scan'208";a="108672421" Date: Wed, 31 May 2017 15:11:29 +0300 From: Jarkko Sakkinen To: "Gustavo A. R. Silva" Cc: Peter Huewe , Marcel Selhorst , Jason Gunthorpe , tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH] char: tmp: fix potential null pointer dereference Message-ID: <20170531121129.f3576lq7peott6gd@intel.com> References: <20170530215123.GA7484@embeddedgus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170530215123.GA7484@embeddedgus> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 30, 2017 at 04:51:23PM -0500, Gustavo A. R. Silva wrote: > NULL check at line 147: if (chip) {, implies chip might be NULL. > Function dev_get_drvdata() dereference pointer chip. > Move pointer priv assignment inside the IF block that checks > pointer chip. > > Addresses-Coverity-ID: 1397646 > Signed-off-by: Gustavo A. R. Silva It cannot be. /Jarkko > --- > drivers/char/tpm/tpm_atmel.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/char/tpm/tpm_atmel.c b/drivers/char/tpm/tpm_atmel.c > index 0d322ab..0826efd 100644 > --- a/drivers/char/tpm/tpm_atmel.c > +++ b/drivers/char/tpm/tpm_atmel.c > @@ -142,9 +142,10 @@ static struct platform_device *pdev; > static void atml_plat_remove(void) > { > struct tpm_chip *chip = dev_get_drvdata(&pdev->dev); > - struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev); > + struct tpm_atmel_priv *priv; > > if (chip) { > + priv = dev_get_drvdata(&chip->dev); > tpm_chip_unregister(chip); > if (priv->have_region) > atmel_release_region(priv->base, priv->region_size); > -- > 2.5.0 >