[PATCH 5.13 725/800] iio: light: vcnl4035: Fix buffer alignment in iio_push_to_buffers_with_timestamp()

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 04:54:36 EST


From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>

[ Upstream commit ec90b52c07c0403a6db60d752484ec08d605ead0 ]

Add __aligned(8) to ensure the buffer passed to
iio_push_to_buffers_with_timestamp() is suitable for the naturally
aligned timestamp that will be inserted.

Here an explicit structure is not used, because the holes would
necessitate the addition of an explict memset(), to avoid a potential
kernel data leak, making for a less minimal fix.

Fixes: 55707294c4eb ("iio: light: Add support for vishay vcnl4035")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Cc: Parthiban Nallathambi <pn@xxxxxxx>
Reviewed-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210613152301.571002-8-jic23@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/iio/light/vcnl4035.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/light/vcnl4035.c b/drivers/iio/light/vcnl4035.c
index ae87740d9cef..bc0777411712 100644
--- a/drivers/iio/light/vcnl4035.c
+++ b/drivers/iio/light/vcnl4035.c
@@ -102,7 +102,8 @@ static irqreturn_t vcnl4035_trigger_consumer_handler(int irq, void *p)
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct vcnl4035_data *data = iio_priv(indio_dev);
- u8 buffer[ALIGN(sizeof(u16), sizeof(s64)) + sizeof(s64)];
+ /* Ensure naturally aligned timestamp */
+ u8 buffer[ALIGN(sizeof(u16), sizeof(s64)) + sizeof(s64)] __aligned(8);
int ret;

ret = regmap_read(data->regmap, VCNL4035_ALS_DATA, (int *)buffer);
--
2.30.2