[PATCH] leds: leds-ns2: Add of_node_put() before return

[PATCH] leds: leds-ns2: Add of_node_put() before return

[Nishka Dasgupta]

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. Hence add an of_node_put before the return in
four places.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
---
 drivers/leds/leds-ns2.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/leds/leds-ns2.c b/drivers/leds/leds-ns2.c
index f92e2c07c1c6..6e47c21ef1c4 100644
--- a/drivers/leds/leds-ns2.c
+++ b/drivers/leds/leds-ns2.c
@@ -263,12 +263,16 @@ ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
 		struct ns2_led_modval *modval;
 
 		ret = of_get_named_gpio(child, "cmd-gpio", 0);
-		if (ret < 0)
+		if (ret < 0) {
+			of_node_put(child);
 			return ret;
+		}
 		led->cmd = ret;
 		ret = of_get_named_gpio(child, "slow-gpio", 0);
-		if (ret < 0)
+		if (ret < 0) {
+			of_node_put(child);
 			return ret;
+		}
 		led->slow = ret;
 		ret = of_property_read_string(child, "label", &string);
 		led->name = (ret == 0) ? string : child->name;
@@ -281,6 +285,7 @@ ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
 		if (ret < 0 || ret % 3) {
 			dev_err(dev,
 				"Missing or malformed modes-map property\n");
+			of_node_put(child);
 			return -EINVAL;
 		}
 
@@ -289,8 +294,10 @@ ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
 				      num_modes,
 				      sizeof(struct ns2_led_modval),
 				      GFP_KERNEL);
-		if (!modval)
+		if (!modval) {
+			of_node_put(child);
 			return -ENOMEM;
+		}
 
 		for (i = 0; i < num_modes; i++) {
 			of_property_read_u32_index(child,
-- 
2.19.1

Re: [PATCH] leds: leds-ns2: Add of_node_put() before return

[Jacek Anaszewski]

Hi Nishka,

Thank you for the patch.

Please apply err_node_put scheme similarly like you've already
done that for leds-max77650.

Best regards,
Jacek Anaszewski

On 7/9/19 7:34 PM, Nishka Dasgupta wrote:
> 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. Hence add an of_node_put before the return in
> four places.
> Issue found with Coccinelle.
> 
> Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
> ---
>  drivers/leds/leds-ns2.c | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/leds/leds-ns2.c b/drivers/leds/leds-ns2.c
> index f92e2c07c1c6..6e47c21ef1c4 100644
> --- a/drivers/leds/leds-ns2.c
> +++ b/drivers/leds/leds-ns2.c
> @@ -263,12 +263,16 @@ ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
>  		struct ns2_led_modval *modval;
>  
>  		ret = of_get_named_gpio(child, "cmd-gpio", 0);
> -		if (ret < 0)
> +		if (ret < 0) {
> +			of_node_put(child);
>  			return ret;
> +		}
>  		led->cmd = ret;
>  		ret = of_get_named_gpio(child, "slow-gpio", 0);
> -		if (ret < 0)
> +		if (ret < 0) {
> +			of_node_put(child);
>  			return ret;
> +		}
>  		led->slow = ret;
>  		ret = of_property_read_string(child, "label", &string);
>  		led->name = (ret == 0) ? string : child->name;
> @@ -281,6 +285,7 @@ ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
>  		if (ret < 0 || ret % 3) {
>  			dev_err(dev,
>  				"Missing or malformed modes-map property\n");
> +			of_node_put(child);
>  			return -EINVAL;
>  		}
>  
> @@ -289,8 +294,10 @@ ns2_leds_get_of_pdata(struct device *dev, struct ns2_led_platform_data *pdata)
>  				      num_modes,
>  				      sizeof(struct ns2_led_modval),
>  				      GFP_KERNEL);
> -		if (!modval)
> +		if (!modval) {
> +			of_node_put(child);
>  			return -ENOMEM;
> +		}
>  
>  		for (i = 0; i < num_modes; i++) {
>  			of_property_read_u32_index(child,
>