[PATCH 4.14 41/85] of/address: Fix of_node memory leak in of_dma_is_coherent

[Greg Kroah-Hartman]

From: Evan Nimmo <evan.nimmo@xxxxxxxxxxxxxxxxxxx>

[ Upstream commit a5bea04fcc0b3c0aec71ee1fd58fd4ff7ee36177 ]

Commit dabf6b36b83a ("of: Add OF_DMA_DEFAULT_COHERENT & select it on
powerpc") added a check to of_dma_is_coherent which returns early
if OF_DMA_DEFAULT_COHERENT is enabled. This results in the of_node_put()
being skipped causing a memory leak. Moved the of_node_get() below this
check so we now we only get the node if OF_DMA_DEFAULT_COHERENT is not
enabled.

Fixes: dabf6b36b83a ("of: Add OF_DMA_DEFAULT_COHERENT & select it on powerpc")
Signed-off-by: Evan Nimmo <evan.nimmo@xxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20201110022825.30895-1-evan.nimmo@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/of/address.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/of/address.c b/drivers/of/address.c
index 456339c19aed7..94f4ff22044f6 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -899,11 +899,13 @@ EXPORT_SYMBOL_GPL(of_dma_get_range);
  */
 bool of_dma_is_coherent(struct device_node *np)
 {
-	struct device_node *node = of_node_get(np);
+	struct device_node *node;
 
 	if (IS_ENABLED(CONFIG_OF_DMA_DEFAULT_COHERENT))
 		return true;
 
+	node = of_node_get(np);
+
 	while (node) {
 		if (of_property_read_bool(node, "dma-coherent")) {
 			of_node_put(node);
-- 
2.27.0