linux-kernel - Re: [PATCH] GPIO_KEYS: If devm_add_action() fails, we are explicitly calling the cleanup to freethe resources allocated. Use the helper devm_add_action_or_reset() and return directly in case of error, since the cleanup function has been already called by the helper if there was any error.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 5 Jul 2016 10:01:11 -0700
From:	Bjorn Andersson <bjorn.andersson@...aro.org>
To:	Arvind Yadav <arvind.yadav.cs@...il.com>
Cc:	dmitry.torokhov@...il.com, ldewangan@...dia.com,
	linus.walleij@...aro.org, van.freenix@...il.com,
	bjorn.andersson@...ymobile.com, linux-input@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] GPIO_KEYS: If devm_add_action() fails, we are explicitly
 calling the cleanup to freethe resources allocated. Use the helper
 devm_add_action_or_reset() and return directly in case of error, since the
 cleanup function has been already called by the helper if there was any
 error.

On Tue 05 Jul 09:18 PDT 2016, Arvind Yadav wrote:

Your subject line should be a short and descriptive summary, followed by
an empty line and then potentially a longer description motivating your
patch.  Please read section #14 of Documentation/SubmittingPatches.

> Signed-off-by: Arvind Yadav <arvind.yadav.cs@...il.com>
> ---
>  drivers/input/keyboard/gpio_keys.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
> index 2909365..a2fa3bb 100644
> --- a/drivers/input/keyboard/gpio_keys.c
> +++ b/drivers/input/keyboard/gpio_keys.c
> @@ -542,7 +542,8 @@ static int gpio_keys_setup_key(struct platform_device *pdev,
>  	 * Install custom action to cancel release timer and
>  	 * workqueue item.
>  	 */
> -	error = devm_add_action(&pdev->dev, gpio_keys_quiesce_key, bdata);
> +	error = devm_add_action_or_reset(&pdev->dev, gpio_keys_quiesce_key,
> +					bdata);

The code leading up to this initializes the timer and work struct, but
they are not triggered unless their respective isr is exectued. This
would not happen until after the request_irq at the end of the function.

As such there doesn't appear to be a reason for cancelling any work or
timers.

>  	if (error) {
>  		dev_err(&pdev->dev,
>  			"failed to register quiesce action, error: %d\n",

Regards,
Bjorn