[PATCH] gpiolib: Free the last requested descriptor

[PATCH] gpiolib: Free the last requested descriptor

[Ricardo Ribalda Delgado]

The current code only frees N-1 gpios if an error occurs during
gpiod_set_transitory, gpiod_direction_output or gpiod_direction_input.
Leading to gpios that cannot be used by userspace nor other drivers.

Cc: Timur Tabi <timur@codeaurora.org>
Cc: stable@vger.kernel.org
Fixes: ab3dbcf78f60f46d ("gpioib: do not free unrequested descriptors)
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
---
 drivers/gpio/gpiolib.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index e8f8a1999393..a57300c1d649 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -571,7 +571,7 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
 		if (ret)
 			goto out_free_descs;
 		lh->descs[i] = desc;
-		count = i;
+		count = i + 1;
 
 		if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
 			set_bit(FLAG_ACTIVE_LOW, &desc->flags);
-- 
2.18.0

Re: [PATCH] gpiolib: Free the last requested descriptor

[Ricardo Ribalda Delgado]

Reported-by: Jan Lorenzen <jl@newtec.dk>
On Thu, Sep 13, 2018 at 3:37 PM Ricardo Ribalda Delgado
<ricardo.ribalda@gmail.com> wrote:
>
> The current code only frees N-1 gpios if an error occurs during
> gpiod_set_transitory, gpiod_direction_output or gpiod_direction_input.
> Leading to gpios that cannot be used by userspace nor other drivers.
>
> Cc: Timur Tabi <timur@codeaurora.org>
> Cc: stable@vger.kernel.org
> Fixes: ab3dbcf78f60f46d ("gpioib: do not free unrequested descriptors)
> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
> ---
>  drivers/gpio/gpiolib.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index e8f8a1999393..a57300c1d649 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -571,7 +571,7 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
>                 if (ret)
>                         goto out_free_descs;
>                 lh->descs[i] = desc;
> -               count = i;
> +               count = i + 1;
>
>                 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
>                         set_bit(FLAG_ACTIVE_LOW, &desc->flags);
> --
> 2.18.0
>


-- 
Ricardo Ribalda

Re: [PATCH] gpiolib: Free the last requested descriptor

[Linus Walleij]

On Thu, Sep 13, 2018 at 3:37 PM Ricardo Ribalda Delgado
<ricardo.ribalda@gmail.com> wrote:

> The current code only frees N-1 gpios if an error occurs during
> gpiod_set_transitory, gpiod_direction_output or gpiod_direction_input.
> Leading to gpios that cannot be used by userspace nor other drivers.
>
> Cc: Timur Tabi <timur@codeaurora.org>
> Cc: stable@vger.kernel.org
> Fixes: ab3dbcf78f60f46d ("gpioib: do not free unrequested descriptors)
> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>

Patch applied for fixes with Jan's Reported-by tag.

Yours,
Linus Walleij

Re: [PATCH] gpiolib: Free the last requested descriptor

[Ricardo Ribalda Delgado]

Hi Linus
On Fri, Sep 14, 2018 at 10:56 AM Linus Walleij <linus.walleij@linaro.org> wrote:
>
> On Thu, Sep 13, 2018 at 3:37 PM Ricardo Ribalda Delgado
> <ricardo.ribalda@gmail.com> wrote:
>
> > The current code only frees N-1 gpios if an error occurs during
> > gpiod_set_transitory, gpiod_direction_output or gpiod_direction_input.
> > Leading to gpios that cannot be used by userspace nor other drivers.
> >
> > Cc: Timur Tabi <timur@codeaurora.org>
> > Cc: stable@vger.kernel.org
> > Fixes: ab3dbcf78f60f46d ("gpioib: do not free unrequested descriptors)
> > Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
>
> Patch applied for fixes with Jan's Reported-by tag.

Just a heads-up

I haven't seem the patch on your kernel tree at
https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio.git/refs/heads

it is probably on your computer tree, but I wanted to make sure the
patch is not lost in the wind :P

Thanks!


>
> Yours,
> Linus Walleij



-- 
Ricardo Ribalda

Re: [PATCH] gpiolib: Free the last requested descriptor

[Linus Walleij]

On Mon, Sep 17, 2018 at 3:14 AM Ricardo Ribalda Delgado
<ricardo.ribalda@gmail.com> wrote:

> Just a heads-up
>
> I haven't seem the patch on your kernel tree at
> https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio.git/refs/heads
>
> it is probably on your computer tree, but I wanted to make sure the
> patch is not lost in the wind :P

I was just travelling, it's in there now and pushed for next!

Yours,
Linus Walleij