[PATCH 5.10 520/593] iio: light: vcnl4000: Fix buffer alignment in iio_push_to_buffers_with_timestamp()

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 03:13:07 EST


From: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>

[ Upstream commit dce793c0ab00c35039028fdcd5ce123805a01361 ]

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 kernel
data leak, making for a less minimal fix.

Found during an audit of all callers of iio_push_to_buffers_with_timestamp()

Fixes: 8fe78d5261e7 ("iio: vcnl4000: Add buffer support for VCNL4010/20.")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Cc: Mathieu Othacehe <m.othacehe@xxxxxxxxx>
Reviewed-by: Nuno Sá <nuno.sa@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210613152301.571002-7-jic23@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/iio/light/vcnl4000.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
index fff4b36b8b58..f4feb44903b3 100644
--- a/drivers/iio/light/vcnl4000.c
+++ b/drivers/iio/light/vcnl4000.c
@@ -910,7 +910,7 @@ static irqreturn_t vcnl4010_trigger_handler(int irq, void *p)
struct iio_dev *indio_dev = pf->indio_dev;
struct vcnl4000_data *data = iio_priv(indio_dev);
const unsigned long *active_scan_mask = indio_dev->active_scan_mask;
- u16 buffer[8] = {0}; /* 1x16-bit + ts */
+ u16 buffer[8] __aligned(8) = {0}; /* 1x16-bit + naturally aligned ts */
bool data_read = false;
unsigned long isr;
int val = 0;
--
2.30.2