soc: microchip: mpfs: Fix memory leak in mpfs_sys_controller_probe()

[ Upstream commit 5a741f8 ]

In mpfs_sys_controller_probe(), if of_get_mtd_device_by_node() fails,
the function returns immediately without freeing the allocated memory
for sys_controller, leading to a memory leak.

Fix this by jumping to the out_free label to ensure the memory is
properly freed.

Also, consolidate the error handling for the mbox_request_channel()
failure case to use the same label.

Fixes: 742aa6c ("soc: microchip: mpfs: enable access to the system controller's flash")
Co-developed-by: Jianhao Xu <jianhao.xu@seu.edu.cn>
Signed-off-by: Jianhao Xu <jianhao.xu@seu.edu.cn>
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: GoodLuck612

drivers/soc/microchip/mpfs-sys-controller.c

@@ -142,8 +142,10 @@ static int mpfs_sys_controller_probe(struct platform_device *pdev)
 
 	sys_controller->flash = of_get_mtd_device_by_node(np);
 	of_node_put(np);
-	if (IS_ERR(sys_controller->flash))
-		return dev_err_probe(dev, PTR_ERR(sys_controller->flash), "Failed to get flash\n");
+	if (IS_ERR(sys_controller->flash)) {
+		ret = dev_err_probe(dev, PTR_ERR(sys_controller->flash), "Failed to get flash\n");
+		goto out_free;
+	}
 
 no_flash:
 	sys_controller->client.dev = dev;
@@ -155,8 +157,7 @@ static int mpfs_sys_controller_probe(struct platform_device *pdev)
 	if (IS_ERR(sys_controller->chan)) {
 		ret = dev_err_probe(dev, PTR_ERR(sys_controller->chan),
 				    "Failed to get mbox channel\n");
-		kfree(sys_controller);
-		return ret;
+		goto out_free;
 	}
 
 	init_completion(&sys_controller->c);
@@ -174,6 +175,10 @@ static int mpfs_sys_controller_probe(struct platform_device *pdev)
 	dev_info(&pdev->dev, "Registered MPFS system controller\n");
 
 	return 0;
+
+out_free:
+	kfree(sys_controller);
+	return ret;
 }
 
 static void mpfs_sys_controller_remove(struct platform_device *pdev)