From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752398AbbJWHhj (ORCPT ); Fri, 23 Oct 2015 03:37:39 -0400 Received: from mga03.intel.com ([134.134.136.65]:2690 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752250AbbJWHhi (ORCPT ); Fri, 23 Oct 2015 03:37:38 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,185,1444719600"; d="scan'208";a="670130582" Date: Fri, 23 Oct 2015 10:37:33 +0300 From: Jarkko Sakkinen To: Christophe JAILLET Cc: peterhuewe@gmx.de, tpmdd@selhorst.net, tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH] TPM: Avoid reference to potentially freed memory Message-ID: <20151023073733.GA6941@intel.com> References: <1445545961-5620-1-git-send-email-christophe.jaillet@wanadoo.fr> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1445545961-5620-1-git-send-email-christophe.jaillet@wanadoo.fr> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 22, 2015 at 10:32:41PM +0200, Christophe JAILLET wrote: > Reference to the 'np' node is dropped before dereferencing the 'sizep' and > 'basep' pointers, which could by then point to junk if the node has been > freed. > > Refactor code to call 'of_node_pup' later. > > Signed-off-by: Christophe JAILLET LGTM. Reviewed-by: Jarkko Sakkinen > --- > drivers/char/tpm/tpm_of.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/char/tpm/tpm_of.c b/drivers/char/tpm/tpm_of.c > index 1141456..570f30c 100644 > --- a/drivers/char/tpm/tpm_of.c > +++ b/drivers/char/tpm/tpm_of.c > @@ -53,17 +53,18 @@ int read_log(struct tpm_bios_log *log) > goto cleanup_eio; > } > > - of_node_put(np); > log->bios_event_log = kmalloc(*sizep, GFP_KERNEL); > if (!log->bios_event_log) { > pr_err("%s: ERROR - Not enough memory for BIOS measurements\n", > __func__); > + of_node_put(np); > return -ENOMEM; > } > > log->bios_event_log_end = log->bios_event_log + *sizep; > > memcpy(log->bios_event_log, __va(*basep), *sizep); > + of_node_put(np); > > return 0; > > -- > 2.1.4 > /Jarkko