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Date:   Mon, 27 Nov 2023 08:13:13 +0100
From:   Florian Eckert <fe@dev.tdt.de>
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     Eckert.Florian@googlemail.com, jirislaby@kernel.org, pavel@ucw.cz,
        lee@kernel.org, kabel@kernel.org, u.kleine-koenig@pengutronix.de,
        m.brock@vanmierlo.com, linux-kernel@vger.kernel.org,
        linux-serial@vger.kernel.org, linux-leds@vger.kernel.org
Subject: Re: [Patch v8 2/6] leds: ledtrig-tty: free allocated ttyname buffer
 on deactivate
In-Reply-To: <2023112356-amount-undertook-cdb2@gregkh>
References: <20231109085038.371977-1-fe@dev.tdt.de>
 <20231109085038.371977-3-fe@dev.tdt.de>
 <2023112356-amount-undertook-cdb2@gregkh>
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On 2023-11-23 15:06, Greg KH wrote:
> On Thu, Nov 09, 2023 at 09:50:34AM +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")
>> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
>> 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;
>> +
> 
> This should be a stand-alone patch with a proper cc: stable tag added 
> as
> well so that it can be accepted now, as it is independent of this new
> feature you are adding.

I already send this to stable@vger.kernel.org [1].
The patch already got an 'Reviewed-by:' from Uwe [2].
I hope I did everything right and it only slipped through?

I will omit the patch from the v9 patchset of 'ledtrig-tty'.
This patch set will come later today with your requested changes.

Links;
[1] 
https://lore.kernel.org/stable/20231106141205.3376954-1-fe@dev.tdt.de/
[2] 
https://lore.kernel.org/stable/20231106144914.bflq2jxejdxs6zjb@pengutronix.de/

Best regards

Florian