linux-kernel - [PATCH AUTOSEL 5.2 40/76] iommu/vt-d: Check if domain->pgd was allocated

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20190802131951.11600-40-sashal@kernel.org>
Date:   Fri,  2 Aug 2019 09:19:14 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Dmitry Safonov <dima@...sta.com>,
        David Woodhouse <dwmw2@...radead.org>,
        Joerg Roedel <joro@...tes.org>,
        Lu Baolu <baolu.lu@...ux.intel.com>,
        iommu@...ts.linux-foundation.org, Joerg Roedel <jroedel@...e.de>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH AUTOSEL 5.2 40/76] iommu/vt-d: Check if domain->pgd was allocated

From: Dmitry Safonov <dima@...sta.com>

[ Upstream commit 3ee9eca760e7d0b68c55813243de66bbb499dc3b ]

There is a couple of places where on domain_init() failure domain_exit()
is called. While currently domain_init() can fail only if
alloc_pgtable_page() has failed.

Make domain_exit() check if domain->pgd present, before calling
domain_unmap(), as it theoretically should crash on clearing pte entries
in dma_pte_clear_level().

Cc: David Woodhouse <dwmw2@...radead.org>
Cc: Joerg Roedel <joro@...tes.org>
Cc: Lu Baolu <baolu.lu@...ux.intel.com>
Cc: iommu@...ts.linux-foundation.org
Signed-off-by: Dmitry Safonov <dima@...sta.com>
Reviewed-by: Lu Baolu <baolu.lu@...ux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@...e.de>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/iommu/intel-iommu.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 2101601adf57d..1ad24367373f4 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -1900,7 +1900,6 @@ static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu,
 
 static void domain_exit(struct dmar_domain *domain)
 {
-	struct page *freelist;
 
 	/* Remove associated devices and clear attached or cached domains */
 	rcu_read_lock();
@@ -1910,9 +1909,12 @@ static void domain_exit(struct dmar_domain *domain)
 	/* destroy iovas */
 	put_iova_domain(&domain->iovad);
 
-	freelist = domain_unmap(domain, 0, DOMAIN_MAX_PFN(domain->gaw));
+	if (domain->pgd) {
+		struct page *freelist;
 
-	dma_free_pagelist(freelist);
+		freelist = domain_unmap(domain, 0, DOMAIN_MAX_PFN(domain->gaw));
+		dma_free_pagelist(freelist);
+	}
 
 	free_domain_mem(domain);
 }
-- 
2.20.1