iommu/tegra: gart: Fix NULL pointer dereference

digetx · joergroedel · commit 8e924910dd07 · 2019-01-16T13:54:14.000+01:00
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 &lt;digetx@gmail.com&gt;
Acked-by: Thierry Reding &lt;treding@nvidia.com&gt;
Signed-off-by: Joerg Roedel &lt;jroedel@suse.de&gt;
diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
@@ -260,9 +260,9 @@ 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);
