[PATCH v3 13/19] iommu/tegra: gart: Fix NULL pointer dereference

From: Dmitry Osipenko <digetx@gmail.com>
To: Joerg Roedel <joro@8bytes.org>,
	Robin Murphy <robin.murphy@arm.com>,
	Thierry Reding <thierry.reding@gmail.com>,
	Jonathan Hunter <jonathanh@nvidia.com>,
	Rob Herring <robh+dt@kernel.org>
Cc: iommu@lists.linux-foundation.org, devicetree@vger.kernel.org,
	linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v3 13/19] iommu/tegra: gart: Fix NULL pointer dereference
Date: Sat, 18 Aug 2018 18:54:24 +0300	[thread overview]
Message-ID: <20180818155430.5586-14-digetx@gmail.com> (raw)
In-Reply-To: <20180818155430.5586-1-digetx@gmail.com>

Fix NULL pointer dereference on IOMMU domain destruction that happens
because clients list is being iterated unsafely and its elements are
getting deleted during the iteration.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 drivers/iommu/tegra-gart.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
index e6fe139576c3..1d45b023adea 100644
--- a/drivers/iommu/tegra-gart.c
+++ b/drivers/iommu/tegra-gart.c
@@ -258,9 +258,9 @@ static void gart_iommu_domain_free(struct iommu_domain *domain)
 	if (gart) {
 		spin_lock(&gart->client_lock);
 		if (!list_empty(&gart->client)) {
-			struct gart_client *c;
+			struct gart_client *c, *tmp;
 
-			list_for_each_entry(c, &gart->client, list)
+			list_for_each_entry_safe(c, tmp, &gart->client, list)
 				__gart_iommu_detach_dev(domain, c->dev);
 		}
 		spin_unlock(&gart->client_lock);
-- 
2.18.0

