From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> commit 198cf32f0503d2ad60d320b95ef6fb8243db857f upstream. Whilst this is another case of the issue Lars reported with an array of elements of smaller than 8 bytes being passed to iio_push_to_buffers_with_timestamp(), the solution here is a bit different from the other cases and relies on __aligned working on the stack (true since 4.6?) This one is unusual. We have to do an explicit memset() each time as we are reading 3 bytes into a potential 4 byte channel which may sometimes be a 2 byte channel depending on what is enabled. As such, moving the buffer to the heap in the iio_priv structure doesn't save us much. We can't use a nice explicit structure on the stack either as the data channels have different storage sizes and are all separately controlled. Fixes: cc26ad455f57 ("iio: Add Freescale MPL3115A2 pressure / temperature sensor driver") Reported-by: Lars-Peter Clausen <lars@xxxxxxxxxx> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx> Reviewed-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> Cc: Peter Meerwald <pmeerw@xxxxxxxxxx> Cc: <Stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200920112742.170751-7-jic23@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iio/pressure/mpl3115.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/drivers/iio/pressure/mpl3115.c +++ b/drivers/iio/pressure/mpl3115.c @@ -147,7 +147,14 @@ static irqreturn_t mpl3115_trigger_handl struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct mpl3115_data *data = iio_priv(indio_dev); - u8 buffer[16]; /* 32-bit channel + 16-bit channel + padding + ts */ + /* + * 32-bit channel + 16-bit channel + padding + ts + * Note that it is possible for only one of the first 2 + * channels to be enabled. If that happens, the first element + * of the buffer may be either 16 or 32-bits. As such we cannot + * use a simple structure definition to express this data layout. + */ + u8 buffer[16] __aligned(8); int ret, pos = 0; mutex_lock(&data->lock);