From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751057AbdAMAs3 (ORCPT ); Thu, 12 Jan 2017 19:48:29 -0500 Received: from mail-pf0-f174.google.com ([209.85.192.174]:36226 "EHLO mail-pf0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750806AbdAMAs2 (ORCPT ); Thu, 12 Jan 2017 19:48:28 -0500 Subject: Re: [PATCH] PCI: iproc: fix kernel crash if dev->of_node not defined To: Florian Fainelli , Abylay Ospan , Bjorn Helgaas , Ray Jui , Scott Branden , Jon Mason , bcm-kernel-feedback-list@broadcom.com, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <1484266817-6725-1-git-send-email-aospan@netup.ru> <6891f43f-25e7-1411-800e-97e6788f2f27@gmail.com> From: Ray Jui Message-ID: Date: Thu, 12 Jan 2017 16:48:25 -0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:50.0) Gecko/20100101 Thunderbird/50.0 MIME-Version: 1.0 In-Reply-To: <6891f43f-25e7-1411-800e-97e6788f2f27@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Florian, On 1/12/2017 4:22 PM, Florian Fainelli wrote: > On 01/12/2017 04:20 PM, Abylay Ospan wrote: >> pcie->dev->of_node not always defined (NULL) and can cause crash: >> >> [ 19.053195] Unable to handle kernel NULL pointer dereference at >> virtual address 00000020 >> [] (of_n_addr_cells) from [] >> (iproc_pcie_setup+0x30c/0xce0) >> >> this patch adds sanity check to prevent crash. > > Humm, how can it not be defined based on your earlier comment that you > are using this on NSP which is Device Tree exclusively? I would agree if > this was seen on e.g: MIPS/BCMA (47xx). I thought Abylay mentioned: "Tested on Broadcom NorthStar machine ('Edgecore ECW7220-L') with two PCIe wifi adapters (b43 BCM4331 and ath10k QCA988X)." That is a NorthStar device which is BCMA based? > >> >> Signed-off-by: Abylay Ospan >> --- >> drivers/pci/host/pcie-iproc.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c >> index 3ebc025..f2836a9 100644 >> --- a/drivers/pci/host/pcie-iproc.c >> +++ b/drivers/pci/host/pcie-iproc.c >> @@ -952,6 +952,9 @@ static int pci_dma_range_parser_init(struct of_pci_range_parser *parser, >> const int na = 3, ns = 2; >> int rlen; >> >> + if (!node) >> + return -ENOENT; >> + >> parser->node = node; >> parser->pna = of_n_addr_cells(node); >> parser->np = parser->pna + na + ns; >> > >