From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756200AbcDGMlT (ORCPT ); Thu, 7 Apr 2016 08:41:19 -0400 Received: from 8bytes.org ([81.169.241.247]:38184 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755633AbcDGMlS (ORCPT ); Thu, 7 Apr 2016 08:41:18 -0400 From: Joerg Roedel To: iommu@lists.linux-foundation.org Cc: linux-kernel@vger.kernel.org, Joerg Roedel , stable@vger.kernel.org Subject: [PATCH] iommu: Don't overwrite domain pointer when there is no default_domain Date: Thu, 7 Apr 2016 14:40:39 +0200 Message-Id: <1460032852-1936-1-git-send-email-joro@8bytes.org> 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 From: Joerg Roedel IOMMU drivers that do not support default domains, but make use of the the group->domain pointer can get that pointer overwritten with NULL on device add/remove. Make sure this can't happen by only overwriting the domain pointer when it is NULL. Cc: stable@vger.kernel.org #v4.4+ Fixes: 1228236de5f9 ('iommu: Move default domain allocation to iommu_group_get_for_dev()') Signed-off-by: Joerg Roedel --- drivers/iommu/iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index bfd4f7c..b9df141 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -848,7 +848,8 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev) if (!group->default_domain) { group->default_domain = __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_DMA); - group->domain = group->default_domain; + if (!group->domain) + group->domain = group->default_domain; } ret = iommu_group_add_device(group, dev); -- 1.8.4.5