[PATCH] pinctrl: imx1: fix device_node leak in dt_is_flat_functions()

[PATCH] pinctrl: imx1: fix device_node leak in dt_is_flat_functions()

[Felix Gu]

for_each_child_of_node() holds a reference on the iterator node that
must be released on early return. imx1_pinctrl_dt_is_flat_functions()
has two early return paths inside the loop that skip this cleanup.

Replace both loops with the scoped variant so that the reference is
automatically dropped when the iterator goes out of scope.

Fixes: 63d2059cd665 ("pinctrl: imx1: Allow parsing DT without function nodes")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
---
 drivers/pinctrl/freescale/pinctrl-imx1-core.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/pinctrl/freescale/pinctrl-imx1-core.c b/drivers/pinctrl/freescale/pinctrl-imx1-core.c
index b7bd4ef9c0db..4a6bdaefa42f 100644
--- a/drivers/pinctrl/freescale/pinctrl-imx1-core.c
+++ b/drivers/pinctrl/freescale/pinctrl-imx1-core.c
@@ -547,14 +547,11 @@ static int imx1_pinctrl_parse_functions(struct device_node *np,
  */
 static bool imx1_pinctrl_dt_is_flat_functions(struct device_node *np)
 {
-	struct device_node *function_np;
-	struct device_node *pinctrl_np;
-
-	for_each_child_of_node(np, function_np) {
+	for_each_child_of_node_scoped(np, function_np) {
 		if (of_property_present(function_np, "fsl,pins"))
 			return true;
 
-		for_each_child_of_node(function_np, pinctrl_np) {
+		for_each_child_of_node_scoped(function_np, pinctrl_np) {
 			if (of_property_present(pinctrl_np, "fsl,pins"))
 				return false;
 		}

---
base-commit: c1ecb239fa3456529a32255359fc78b69eb9d847
change-id: 20260523-pinctrl-imx-b198f8391abf

Best regards,
--  
Felix Gu <ustc.gu@gmail.com>

Re: [PATCH] pinctrl: imx1: fix device_node leak in dt_is_flat_functions()

[Frank Li]

On Sat, May 23, 2026 at 06:27:05PM +0800, Felix Gu wrote:
> for_each_child_of_node() holds a reference on the iterator node that
> must be released on early return. imx1_pinctrl_dt_is_flat_functions()
> has two early return paths inside the loop that skip this cleanup.
>
> Replace both loops with the scoped variant so that the reference is
> automatically dropped when the iterator goes out of scope.
>
> Fixes: 63d2059cd665 ("pinctrl: imx1: Allow parsing DT without function nodes")
> Signed-off-by: Felix Gu <ustc.gu@gmail.com>
> ---

Thank you for fix it.

Reviewed-by: Frank Li <Frank.Li@nxp.com>

>  drivers/pinctrl/freescale/pinctrl-imx1-core.c | 7 ++-----
>  1 file changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/pinctrl/freescale/pinctrl-imx1-core.c b/drivers/pinctrl/freescale/pinctrl-imx1-core.c
> index b7bd4ef9c0db..4a6bdaefa42f 100644
> --- a/drivers/pinctrl/freescale/pinctrl-imx1-core.c
> +++ b/drivers/pinctrl/freescale/pinctrl-imx1-core.c
> @@ -547,14 +547,11 @@ static int imx1_pinctrl_parse_functions(struct device_node *np,
>   */
>  static bool imx1_pinctrl_dt_is_flat_functions(struct device_node *np)
>  {
> -	struct device_node *function_np;
> -	struct device_node *pinctrl_np;
> -
> -	for_each_child_of_node(np, function_np) {
> +	for_each_child_of_node_scoped(np, function_np) {
>  		if (of_property_present(function_np, "fsl,pins"))
>  			return true;
>
> -		for_each_child_of_node(function_np, pinctrl_np) {
> +		for_each_child_of_node_scoped(function_np, pinctrl_np) {
>  			if (of_property_present(pinctrl_np, "fsl,pins"))
>  				return false;
>  		}
>
> ---
> base-commit: c1ecb239fa3456529a32255359fc78b69eb9d847
> change-id: 20260523-pinctrl-imx-b198f8391abf
>
> Best regards,
> --
> Felix Gu <ustc.gu@gmail.com>
>

Re: [PATCH] pinctrl: imx1: fix device_node leak in dt_is_flat_functions()

[Linus Walleij]

On Sat, May 23, 2026 at 12:27 PM Felix Gu <ustc.gu@gmail.com> wrote:

> for_each_child_of_node() holds a reference on the iterator node that
> must be released on early return. imx1_pinctrl_dt_is_flat_functions()
> has two early return paths inside the loop that skip this cleanup.
>
> Replace both loops with the scoped variant so that the reference is
> automatically dropped when the iterator goes out of scope.
>
> Fixes: 63d2059cd665 ("pinctrl: imx1: Allow parsing DT without function nodes")
> Signed-off-by: Felix Gu <ustc.gu@gmail.com>

So what we got here is a non-critical patch on top of something that was
critical and was merged as fixes. (A minor memory leak is not critical
and not -rc material.)

Linus (the big penguin) has been annoyed of too many noncritical
patches going in as fixes recently so can you please resend this after
the next merge window? (I will try to remember the patch as well.)

Yours,
Linus Walleij

Re: [PATCH] pinctrl: imx1: fix device_node leak in dt_is_flat_functions()

[Linus Walleij]

On Sat, May 23, 2026 at 12:27 PM Felix Gu <ustc.gu@gmail.com> wrote:

> for_each_child_of_node() holds a reference on the iterator node that
> must be released on early return. imx1_pinctrl_dt_is_flat_functions()
> has two early return paths inside the loop that skip this cleanup.
>
> Replace both loops with the scoped variant so that the reference is
> automatically dropped when the iterator goes out of scope.
>
> Fixes: 63d2059cd665 ("pinctrl: imx1: Allow parsing DT without function nodes")
> Signed-off-by: Felix Gu <ustc.gu@gmail.com>

Patch applied for v7.3!

Yours,
Linus Walleij