| Message ID | 20240228204919.3680786-4-andriy.shevchenko@linux.intel.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | iio: core: New macros and making use of them | expand |
On Wed, Feb 28, 2024 at 2:50 PM 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 behind the valid data. > NULLify it for good. > > 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 | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c > index 4302093b92c7..bd305fa87093 100644 > --- a/drivers/iio/industrialio-core.c > +++ b/drivers/iio/industrialio-core.c > @@ -1654,8 +1654,12 @@ 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(struct iio_dev_opaque), IIO_DMA_MINALIGN); > + else > + indio_dev->priv = NULL; Do we actually need the else branch here since we use kzalloc() and therefore indio_dev->priv should already be NULL? > > indio_dev->dev.parent = parent; > indio_dev->dev.type = &iio_device_type; > -- > 2.43.0.rc1.1.gbec44491f096 > >
On Wed, Feb 28, 2024 at 03:06:42PM -0600, David Lechner wrote: > On Wed, Feb 28, 2024 at 2:50 PM Andy Shevchenko > <andriy.shevchenko@linux.intel.com> wrote: ... > > - 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(struct iio_dev_opaque), IIO_DMA_MINALIGN); > > + else > > + indio_dev->priv = NULL; > > Do we actually need the else branch here since we use kzalloc() and > therefore indio_dev->priv should already be NULL? This is more robust, but I'm okay to drop this. Up to Jonathan.
On Wed, 28 Feb 2024 23:36:43 +0200 Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote: > On Wed, Feb 28, 2024 at 03:06:42PM -0600, David Lechner wrote: > > On Wed, Feb 28, 2024 at 2:50 PM Andy Shevchenko > > <andriy.shevchenko@linux.intel.com> wrote: > > ... > > > > - 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(struct iio_dev_opaque), IIO_DMA_MINALIGN); > > > + else > > > + indio_dev->priv = NULL; > > > > Do we actually need the else branch here since we use kzalloc() and > > therefore indio_dev->priv should already be NULL? > > This is more robust, but I'm okay to drop this. Up to Jonathan. > Given the allocation is just above here fine to drop the else in this I think.
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 4302093b92c7..bd305fa87093 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -1654,8 +1654,12 @@ 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(struct iio_dev_opaque), IIO_DMA_MINALIGN); + else + indio_dev->priv = NULL; 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 behind the valid data. NULLify it for good. 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 | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)