leds: ledtrig-tty: free allocated ttyname buffer on deactivate

The ttyname buffer for the ledtrig_tty_data struct is allocated in the
sysfs ttyname_store() function. This buffer must be released on trigger
deactivation. This was missing and is thus a memory leak.

While we are at it, the tty handler in the ledtrig_tty_data struct should
also be returned in case of the trigger deactivation call.

Fixes: fd4a641ac88f ("leds: trigger: implement a tty trigger")
Signed-off-by: Florian Eckert <fe@dev.tdt.de>
---
 drivers/leds/trigger/ledtrig-tty.c | 4 ++++
 1 file changed, 4 insertions(+)

On Mon, Nov 06, 2023 at 02:22:46PM +0100, Florian Eckert wrote:
> The ttyname buffer for the ledtrig_tty_data struct is allocated in the
> sysfs ttyname_store() function. This buffer must be released on trigger
> deactivation. This was missing and is thus a memory leak.
> 
> While we are at it, the tty handler in the ledtrig_tty_data struct should
> also be returned in case of the trigger deactivation call.
> 
> Fixes: fd4a641ac88f ("leds: trigger: implement a tty trigger")
> Signed-off-by: Florian Eckert <fe@dev.tdt.de>
> ---
>  drivers/leds/trigger/ledtrig-tty.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/leds/trigger/ledtrig-tty.c b/drivers/leds/trigger/ledtrig-tty.c
> index 8ae0d2d284af..3e69a7bde928 100644
> --- a/drivers/leds/trigger/ledtrig-tty.c
> +++ b/drivers/leds/trigger/ledtrig-tty.c
> @@ -168,6 +168,10 @@ static void ledtrig_tty_deactivate(struct led_classdev *led_cdev)
>  
>  	cancel_delayed_work_sync(&trigger_data->dwork);
>  
> +	kfree(trigger_data->ttyname);
> +	tty_kref_put(trigger_data->tty);
> +	trigger_data->tty = NULL;
> +
>  	kfree(trigger_data);
>  }
>  
> -- 
> 2.30.2
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
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thanks,

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On Mon, Nov 06, 2023 at 02:22:46PM +0100, Florian Eckert wrote:
> The ttyname buffer for the ledtrig_tty_data struct is allocated in the
> sysfs ttyname_store() function. This buffer must be released on trigger
> deactivation. This was missing and is thus a memory leak.
> 
> While we are at it, the tty handler in the ledtrig_tty_data struct should
> also be returned in case of the trigger deactivation call.
> 
> Fixes: fd4a641ac88f ("leds: trigger: implement a tty trigger")
> Signed-off-by: Florian Eckert <fe@dev.tdt.de>

Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

Thanks
Uwe