fsi: master-gpio: Fix reference count leak in probe error path

[PATCH] fsi: master-gpio: Fix reference count leak in probe error path

Posted by Wentao Liang 1 week, 4 days ago

The function of_node_get() returns a node pointer with its refcount
incremented, but in the error path of the fsi_master_gpio_probe(),
this reference is not released before freeing the master structure,
causing a refcount leak.

Add the missing of_node_put() in the error handling path to properly
release the device tree node reference.

Fixes: 8ef9ccf81044 ("fsi: master-gpio: Add missing release function")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
 drivers/fsi/fsi-master-gpio.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/fsi/fsi-master-gpio.c b/drivers/fsi/fsi-master-gpio.c
index 69de0b5b9cbd..ae9e156284d0 100644
--- a/drivers/fsi/fsi-master-gpio.c
+++ b/drivers/fsi/fsi-master-gpio.c
@@ -861,6 +861,7 @@ static int fsi_master_gpio_probe(struct platform_device *pdev)
 	}
 	return 0;
  err_free:
+	of_node_put(master->master.dev.of_node);
 	kfree(master);
 	return rc;
 }
-- 
2.34.1

Re: [PATCH] fsi: master-gpio: Fix reference count leak in probe error path

Posted by Markus Elfring 1 week, 3 days ago

…
> Add the missing of_node_put() in the error handling path to properly
> release the device tree node reference.
…
> +++ b/drivers/fsi/fsi-master-gpio.c
> @@ -861,6 +861,7 @@ static int fsi_master_gpio_probe(struct platform_device *pdev)
>  	}
>  	return 0;
>   err_free:
> +	of_node_put(master->master.dev.of_node);

Is there a need to rename the label accordingly?


>  	kfree(master);

Can it be helpful to move the statement “rc = PTR_ERR(gpio);”
also into the exception handling of this function implementation?


>  	return rc;
>  }
…


Regards,
Markus