From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752071AbdHXL4y (ORCPT ); Thu, 24 Aug 2017 07:56:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58490 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751317AbdHXL4x (ORCPT ); Thu, 24 Aug 2017 07:56:53 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com C29EA86647 Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=bhe@redhat.com From: Baoquan He To: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Cc: dan.carpenter@oracle.com, joro@8bytes.org, Baoquan He Subject: [PATCH] iommu/amd: Check if domain is NULL before dereference it Date: Thu, 24 Aug 2017 19:56:47 +0800 Message-Id: <1503575807-15746-1-git-send-email-bhe@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Thu, 24 Aug 2017 11:56:53 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In get_domain(), 'domain' could still be NULL before it's passed to dma_ops_domain() to dereference. For safety, check if 'domain' is NULL before passing to dma_ops_domain(). Reported-by: Dan Carpenter Signed-off-by: Baoquan He --- drivers/iommu/amd_iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 16f1e6af00b0..2e2d5e6a13b3 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -2262,7 +2262,7 @@ static struct protection_domain *get_domain(struct device *dev) domain = to_pdomain(io_domain); attach_device(dev, domain); } - if (!dma_ops_domain(domain)) + if (domain && !dma_ops_domain(domain)) return ERR_PTR(-EBUSY); return domain; -- 2.5.5