| Message ID | 20240304140650.977784-2-andriy.shevchenko@linux.intel.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | iio: core: Fix and cleanup to iio_device_alloc() | expand |
On Mon, Mar 4, 2024 at 8:07 AM Andy Shevchenko <andriy.shevchenko@linux.intel.com> 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@linux.intel.com> > --- Reviewed-by: David Lechner <dlechner@baylibre.com>
On Mon, 4 Mar 2024 16:04:32 +0200 Andy Shevchenko <andriy.shevchenko@linux.intel.com> 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@linux.intel.com> 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;
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;
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@linux.intel.com> --- drivers/iio/industrialio-core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)