From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757981AbcHDLLc (ORCPT ); Thu, 4 Aug 2016 07:11:32 -0400 Received: from mail-pa0-f41.google.com ([209.85.220.41]:35447 "EHLO mail-pa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751541AbcHDLL3 (ORCPT ); Thu, 4 Aug 2016 07:11:29 -0400 Subject: Re: [patch] mailbox: bcm-pdc: potential NULL dereference in pdc_shutdown() To: Dan Carpenter , Jassi Brar , Rob Rice References: <20160804053030.GJ775@mwanda> Cc: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org From: "Rob (William) Rice" Message-ID: Date: Thu, 4 Aug 2016 07:10:10 -0400 User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <20160804053030.GJ775@mwanda> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dan, The fix looks good to me. Thanks for finding and fixing. Rob On 8/4/2016 1:30 AM, Dan Carpenter wrote: > We can't pass NULL pointers to pdc_ring_free() so I moved the check for > NULL. > > Signed-off-by: Dan Carpenter > > diff --git a/drivers/mailbox/bcm-pdc-mailbox.c b/drivers/mailbox/bcm-pdc-mailbox.c > index cbe0c1e..c56d4d0 100644 > --- a/drivers/mailbox/bcm-pdc-mailbox.c > +++ b/drivers/mailbox/bcm-pdc-mailbox.c > @@ -1191,10 +1191,11 @@ static void pdc_shutdown(struct mbox_chan *chan) > { > struct pdc_state *pdcs = chan->con_priv; > > - if (pdcs) > - dev_dbg(&pdcs->pdev->dev, > - "Shutdown mailbox channel for PDC %u", pdcs->pdc_idx); > + if (!pdcs) > + return; > > + dev_dbg(&pdcs->pdev->dev, > + "Shutdown mailbox channel for PDC %u", pdcs->pdc_idx); > pdc_ring_free(pdcs); > } >