[PATCH] leds: qcom-lpg: Release node reference before returning

[PATCH] leds: qcom-lpg: Release node reference before returning

[Deepak R Varma]

The iterator for_each_available_child_of_node() increments the refcount
of the child node it is processing. Release such a reference when the
loop needs to breaks due to en error during its execution.
Issue identified using for_each_child.cocci Coccinelle semantic patch.

Signed-off-by: Deepak R Varma <drv@mailo.com>
---
Please note: The proposed change is compile tested only. I do not have the
necessary hardware to perform additional testing. Please suggest if there is an
alternate means available to further test this change.

 drivers/leds/rgb/leds-qcom-lpg.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/leds/rgb/leds-qcom-lpg.c b/drivers/leds/rgb/leds-qcom-lpg.c
index 67f48f222109..993fb9cf0204 100644
--- a/drivers/leds/rgb/leds-qcom-lpg.c
+++ b/drivers/leds/rgb/leds-qcom-lpg.c
@@ -1112,8 +1112,10 @@ static int lpg_add_led(struct lpg *lpg, struct device_node *np)
 		i = 0;
 		for_each_available_child_of_node(np, child) {
 			ret = lpg_parse_channel(lpg, child, &led->channels[i]);
-			if (ret < 0)
+			if (ret < 0) {
+				of_node_put(child);
 				return ret;
+			}
 
 			info[i].color_index = led->channels[i]->color;
 			info[i].intensity = 0;
@@ -1291,8 +1293,10 @@ static int lpg_probe(struct platform_device *pdev)
 
 	for_each_available_child_of_node(pdev->dev.of_node, np) {
 		ret = lpg_add_led(lpg, np);
-		if (ret)
+		if (ret) {
+			of_node_put(np);
 			return ret;
+		}
 	}
 
 	for (i = 0; i < lpg->num_channels; i++)
-- 
2.34.1

Re: [PATCH] leds: qcom-lpg: Release node reference before returning

[Lee Jones]

On Sat, 11 Feb 2023, Deepak R Varma wrote:

> The iterator for_each_available_child_of_node() increments the refcount
> of the child node it is processing. Release such a reference when the
> loop needs to breaks due to en error during its execution.
> Issue identified using for_each_child.cocci Coccinelle semantic patch.
> 
> Signed-off-by: Deepak R Varma <drv@mailo.com>
> ---
> Please note: The proposed change is compile tested only. I do not have the
> necessary hardware to perform additional testing. Please suggest if there is an
> alternate means available to further test this change.

Please send this again and include the authors.

Perhaps they would be kind enough to test it or provide guidance.
 
>  drivers/leds/rgb/leds-qcom-lpg.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/leds/rgb/leds-qcom-lpg.c b/drivers/leds/rgb/leds-qcom-lpg.c
> index 67f48f222109..993fb9cf0204 100644
> --- a/drivers/leds/rgb/leds-qcom-lpg.c
> +++ b/drivers/leds/rgb/leds-qcom-lpg.c
> @@ -1112,8 +1112,10 @@ static int lpg_add_led(struct lpg *lpg, struct device_node *np)
>  		i = 0;
>  		for_each_available_child_of_node(np, child) {
>  			ret = lpg_parse_channel(lpg, child, &led->channels[i]);
> -			if (ret < 0)
> +			if (ret < 0) {
> +				of_node_put(child);
>  				return ret;
> +			}
>  
>  			info[i].color_index = led->channels[i]->color;
>  			info[i].intensity = 0;
> @@ -1291,8 +1293,10 @@ static int lpg_probe(struct platform_device *pdev)
>  
>  	for_each_available_child_of_node(pdev->dev.of_node, np) {
>  		ret = lpg_add_led(lpg, np);
> -		if (ret)
> +		if (ret) {
> +			of_node_put(np);
>  			return ret;
> +		}
>  	}
>  
>  	for (i = 0; i < lpg->num_channels; i++)
> -- 
> 2.34.1
> 
> 
> 

-- 
Lee Jones [李琼斯]