On Mon, 4 Mar 2024 16:04:32 +0200
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> In iio_device_alloc() when size of the private data is 0,
> the private pointer is calculated to point behind the valid data.
> Leave it NULL when no private data supplied.
>
> Fixes: 6d4ebd565d15 ("iio: core: wrap IIO device into an iio_dev_opaque object")
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Fix is a strong word given any driver trying to access the pointer in this case
will be broken anyway. I don't mind it being backported as it'll make bugs
easier to identify but I'm not rushing it in.
Otherwise seems like a sensible bit of tidying up.
Jonathan
> ---
> drivers/iio/industrialio-core.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index 4302093b92c7..8684ba246969 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -1654,8 +1654,10 @@ struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv)
> return NULL;
>
> indio_dev = &iio_dev_opaque->indio_dev;
> - indio_dev->priv = (char *)iio_dev_opaque +
> - ALIGN(sizeof(struct iio_dev_opaque), IIO_DMA_MINALIGN);
> +
> + if (sizeof_priv)
> + indio_dev->priv = (char *)iio_dev_opaque +
> + ALIGN(sizeof(*iio_dev_opaque), IIO_DMA_MINALIGN);
>
> indio_dev->dev.parent = parent;
> indio_dev->dev.type = &iio_device_type;
