Re: [PATCH v2 05/17] compat_ioctl: move more drivers to generic_compat_ioctl_ptrarg

From: Jonathan Cameron
Date: Mon Sep 17 2018 - 05:34:24 EST


On Wed, 12 Sep 2018 17:08:52 +0200
Arnd Bergmann <arnd@xxxxxxxx> wrote:

> The .ioctl and .compat_ioctl file operations have the same prototype so
> they can both point to the same function, which works great almost all
> the time when all the commands are compatible.
>
> One exception is the s390 architecture, where a compat pointer is only
> 31 bit wide, and converting it into a 64-bit pointer requires calling
> compat_ptr(). Most drivers here will ever run in s390, but since we now
> have a generic helper for it, it's easy enough to use it consistently.
>
> I double-checked all these drivers to ensure that all ioctl arguments
> are used as pointers or are ignored, but are not interpreted as integer
> values.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---

For IIO part.

Acked-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>

Thanks,
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index a062cfddc5af..22844b94b0e9 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -1630,7 +1630,7 @@ static const struct file_operations iio_buffer_fileops = {
> .owner = THIS_MODULE,
> .llseek = noop_llseek,
> .unlocked_ioctl = iio_ioctl,
> - .compat_ioctl = iio_ioctl,
> + .compat_ioctl = generic_compat_ioctl_ptrarg,
> };
>