From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754820Ab1H2TBP (ORCPT ); Mon, 29 Aug 2011 15:01:15 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:54892 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754325Ab1H2TBM (ORCPT ); Mon, 29 Aug 2011 15:01:12 -0400 Subject: [PATCH] x86, pci-nommu: fix potential NULL-ptr dereference in check_addr() From: Arne Redlich To: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Date: Mon, 29 Aug 2011 21:01:00 +0200 Message-ID: <1314644460.11636.2.camel@blackadder> Mime-Version: 1.0 X-Mailer: Evolution 2.32.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org check_addr() dereferences hwdev->dma_mask without first checking that it's actually non-NULL. Signed-off-by: Arne Redlich --- arch/x86/kernel/pci-nommu.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/pci-nommu.c b/arch/x86/kernel/pci-nommu.c index 3af4af8..55b49c7 100644 --- a/arch/x86/kernel/pci-nommu.c +++ b/arch/x86/kernel/pci-nommu.c @@ -16,7 +16,7 @@ static int check_addr(char *name, struct device *hwdev, dma_addr_t bus, size_t size) { if (hwdev && !dma_capable(hwdev, bus, size)) { - if (*hwdev->dma_mask >= DMA_BIT_MASK(32)) + if (hwdev->dma_mask && *hwdev->dma_mask >= DMA_BIT_MASK(32)) printk(KERN_ERR "nommu_%s: overflow %Lx+%zu of device mask %Lx\n", name, (long long)bus, size, -- 1.7.4.1