[PATCH] leds: ledtrig-tty: free allocated ttyname buffer on deactivate

[PATCH] leds: ledtrig-tty: free allocated ttyname buffer on deactivate

[Florian Eckert]

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

Re: [PATCH] leds: ledtrig-tty: free allocated ttyname buffer on deactivate

[Greg KH]

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
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- You have marked a patch with a "Fixes:" tag for a commit that is in an
  older released kernel, yet you do not have a cc: stable line in the
  signed-off-by area at all, which means that the patch will not be
  applied to any older kernel releases.  To properly fix this, please
  follow the documented rules in the
  Documentation/process/stable-kernel-rules.rst file for how to resolve
  this.

If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
from other developers.

thanks,

greg k-h's patch email bot

Re: [PATCH] leds: ledtrig-tty: free allocated ttyname buffer on deactivate

[Uwe Kleine-König]

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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

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |

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