Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934047AbcDLOIJ (ORCPT ); Tue, 12 Apr 2016 10:08:09 -0400 Received: from mail-oi0-f54.google.com ([209.85.218.54]:35203 "EHLO mail-oi0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755941AbcDLOIH (ORCPT ); Tue, 12 Apr 2016 10:08:07 -0400 MIME-Version: 1.0 In-Reply-To: <1460388459-21090-1-git-send-email-sudipm.mukherjee@gmail.com> References: <1460388459-21090-1-git-send-email-sudipm.mukherjee@gmail.com> Date: Tue, 12 Apr 2016 17:08:05 +0300 Message-ID: Subject: Re: [PATCH] mwifiex: fix possible NULL dereference From: Andy Shevchenko To: Sudip Mukherjee Cc: Amitkumar Karwar , Nishant Sarmukadam , Kalle Valo , "linux-kernel@vger.kernel.org" , "open list:TI WILINK WIRELES..." , netdev , Sudip Mukherjee Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1579 Lines: 52 On Mon, Apr 11, 2016 at 6:27 PM, Sudip Mukherjee wrote: > From: Sudip Mukherjee > > We have a check for card just after dereferencing it. So if it is NULL > we have already dereferenced it before its check. Lets dereference it > after checking card for NULL. IIUC the code does nothing with dereference. I would have told NAK if I would have been maintainer. > > Signed-off-by: Sudip Mukherjee > --- > drivers/net/wireless/marvell/mwifiex/pcie.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c > index edf8b07..84562d0 100644 > --- a/drivers/net/wireless/marvell/mwifiex/pcie.c > +++ b/drivers/net/wireless/marvell/mwifiex/pcie.c > @@ -2884,10 +2884,11 @@ static void mwifiex_unregister_dev(struct mwifiex_adapter *adapter) > { > struct pcie_service_card *card = adapter->card; Let's say it's 0. > const struct mwifiex_pcie_card_reg *reg; > - struct pci_dev *pdev = card->dev; This would be equal to offset of dev member in pcie_service_card struct. Nothing wrong here. > + struct pci_dev *pdev; > int i; > > if (card) { > + pdev = card->dev; > if (card->msix_enable) { > for (i = 0; i < MWIFIEX_NUM_MSIX_VECTORS; i++) > synchronize_irq(card->msix_entries[i].vector); > -- > 1.9.1 > -- With Best Regards, Andy Shevchenko