irqchip/irq-mbigen: Add of_node_put() before return

mainline inclusion
from mainline-5.3-rc3
commit 321275f0d8f5
category: bugfix
bugzilla: 20161
CVE: NA

-------------------------------------------------

Each iteration of for_each_child_of_node puts the previous node, but
in the case of a return from the middle of the loop, there is no put,
thus causing a memory leak. Add an of_node_put before the return in
three places.
Issue found with Coccinelle.
Signed-off-by: NNishka Dasgupta <nishkadg.linux@gmail.com>
Signed-off-by: NMarc Zyngier <maz@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Reviewed-by: NHanjun Guo <guohanjun@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

drivers/irqchip/irq-mbigen.c

@@ -252,12 +252,15 @@ static int mbigen_of_create_domain(struct platform_device *pdev,
 
 		parent = platform_bus_type.dev_root;
 		child = of_platform_device_create(np, NULL, parent);
-		if (!child)
+		if (!child) {
+			of_node_put(np);
 			return -ENOMEM;
+		}
 
 		if (of_property_read_u32(child->dev.of_node, "num-pins",
 					 &num_pins) < 0) {
 			dev_err(&pdev->dev, "No num-pins property\n");
+			of_node_put(np);
 			return -EINVAL;
 		}
 
@@ -265,8 +268,10 @@ static int mbigen_of_create_domain(struct platform_device *pdev,
 							   mbigen_write_msg,
 							   &mbigen_domain_ops,
 							   mgn_chip);
-		if (!domain)
+		if (!domain) {
+			of_node_put(np);
 			return -ENOMEM;
+		}
 	}
 
 	return 0;