Re: [PATCH] leds: flash: sgm3140: fix child node reference leak
From: Laurent Pinchart
Date: Mon Sep 14 2026 - 13:11:25 EST
On Mon, Sep 14, 2026 at 09:57:23PM +0800, Guangshuo Li wrote:
> sgm3140_probe() obtains a reference to the LED child node with
> device_get_next_child_node(). The probe error path correctly drops this
> reference with fwnode_handle_put(), but the successful probe path
> returns without releasing it.
>
> v4l2_flash_init() takes its own reference to the supplied fwnode and
> v4l2_flash_release() drops that reference during device removal.
How about devm_led_classdev_flash_register_ext() ?
> Therefore, the reference acquired by sgm3140_probe() is only needed
> during probe and can be released once initialization has completed.
>
> Drop the child node reference before returning successfully from probe.
>
> This issue was found by manual code inspection.
I wonder what prompted you to manual inspect that code.
> Fixes: cef8ec8cbd21 ("leds: add sgm3140 driver")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Guangshuo Li <lgs201920130244@xxxxxxxxx>
> ---
> drivers/leds/flash/leds-sgm3140.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/leds/flash/leds-sgm3140.c b/drivers/leds/flash/leds-sgm3140.c
> index dc6840357370..51e31fdb78e5 100644
> --- a/drivers/leds/flash/leds-sgm3140.c
> +++ b/drivers/leds/flash/leds-sgm3140.c
> @@ -273,7 +273,9 @@ static int sgm3140_probe(struct platform_device *pdev)
> goto err;
> }
>
> - return ret;
> + fwnode_handle_put(child_node);
> +
> + return 0;
>
> err:
> fwnode_handle_put(child_node);
--
Regards,
Laurent Pinchart