dmaengine: qcom: hidma_mgmt: Add of_node_put() before goto

Each iteration of for_each_available_child_of_node puts the previous
node, but in the case of a goto from the middle of the loop, there is
no put, thus causing a memory leak.
Hence add an of_node_put under the label that the gotos point to.
In order to avoid decrementing an already-decremented refcount, copy the
original contents of the label (including the return statement) to just
above the label, so that the code under the label is executed only when
a goto exit from the loop occurs.
Additionally, remove an unnecessary get/put pair from the loop, as the
loop itself already keeps track of refcount.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Acked-by: Sinan Kaya <okaya@kernel.org>
Link: https://lore.kernel.org/r/20190724081609.9724-1-nishkadg.linux@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

1 files changed, 6 insertions, 2 deletions

diff --git a/drivers/dma/qcom/hidma_mgmt.c b/drivers/dma/qcom/hidma_mgmt.c
index 7cb81a50f3f3..806ca02c52d7 100644
--- a/drivers/dma/qcom/hidma_mgmt.c
+++ b/drivers/dma/qcom/hidma_mgmt.c
@@ -387,7 +387,6 @@ static int __init hidma_mgmt_of_populate_channels(struct device_node *np)
 			ret = PTR_ERR(new_pdev);
 			goto out;
 		}
-		of_node_get(child);
 		new_pdev->dev.of_node = child;
 		of_dma_configure(&new_pdev->dev, child, true);
 		/*
@@ -395,9 +394,14 @@ static int __init hidma_mgmt_of_populate_channels(struct device_node *np)
 		 * platforms with or without MSI support.
 		 */
 		of_msi_configure(&new_pdev->dev, child);
-		of_node_put(child);
 	}
+
+	kfree(res);
+
+	return ret;
+
 out:
+	of_node_put(child);
 	kfree(res);
 
 	return ret;