From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751350AbdAPGp2 (ORCPT ); Mon, 16 Jan 2017 01:45:28 -0500 Received: from mail-pf0-f193.google.com ([209.85.192.193]:35451 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750913AbdAPGpX (ORCPT ); Mon, 16 Jan 2017 01:45:23 -0500 From: Arvind Yadav To: ravi@jetztechnologies.com, arvino55@gmail.com Cc: bp@alien8.de, mchehab@kernel.org, linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v1] edac: i82975x_edac :- Handle return NULL error from ioremap_nocache Date: Mon, 16 Jan 2017 12:14:52 +0530 Message-Id: <1484549092-11349-1-git-send-email-arvind.yadav.cs@gmail.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Here, If ioremap_nocache will fail. It will return NULL. Kernel can run into a NULL-pointer dereference. This error check will avoid NULL pointer dereference. Signed-off-by: Arvind Yadav --- drivers/edac/i82975x_edac.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/edac/i82975x_edac.c b/drivers/edac/i82975x_edac.c index 7baa8ac..e747d82 100644 --- a/drivers/edac/i82975x_edac.c +++ b/drivers/edac/i82975x_edac.c @@ -494,6 +494,10 @@ static int i82975x_probe1(struct pci_dev *pdev, int dev_idx) } mchbar &= 0xffffc000; /* bits 31:14 used for 16K window */ mch_window = ioremap_nocache(mchbar, 0x1000); + if (!mch_window) { + edac_dbg(3, "failed to memory map!\n"); + goto fail0; + } #ifdef i82975x_DEBUG_IOMEM i82975x_printk(KERN_INFO, "MCHBAR real = %0x, remapped = %p\n", -- 1.9.1