[PATCH] iommu/of: Fix device node reference leak in of_iommu_get_resv_regions

[Miaoqian Lin <linmq006@gmail.com>]

In of_iommu_get_resv_regions(), of_find_node_by_phandle() returns a device
node with its reference count incremented. The caller is responsible for
releasing this reference when the node is no longer needed.

Add a call to of_node_put() to release the reference after the usage.

Found via static analysis.

Fixes: a5bf3cfce8cb ("iommu: Implement of_iommu_get_resv_regions()")
Cc: stable@vger.kernel.org
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
---
 drivers/iommu/of_iommu.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c
index 6b989a62def2..02448da8ff90 100644
--- a/drivers/iommu/of_iommu.c
+++ b/drivers/iommu/of_iommu.c
@@ -256,6 +256,7 @@ void of_iommu_get_resv_regions(struct device *dev, struct list_head *list)
 				maps = of_translate_dma_region(np, maps, &iova, &length);
 				if (length == 0) {
 					dev_warn(dev, "Cannot reserve IOVA region of 0 size\n");
+					of_node_put(np);
 					continue;
 				}
 				type = iommu_resv_region_get_type(dev, &phys, iova, length);
@@ -265,6 +266,7 @@ void of_iommu_get_resv_regions(struct device *dev, struct list_head *list)
 				if (region)
 					list_add_tail(&region->list, list);
 			}
+			of_node_put(np);
 		}
 	}
 #endif
-- 
2.39.5 (Apple Git-154)