[PATCH 4.4 15/43] iio: imu: adis16480: make sure provided frequency is positive

From: Greg Kroah-Hartman
Date: Mon Nov 11 2019 - 13:30:15 EST


From: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>

commit 24e1eb5c0d78cfb9750b690bbe997d4d59170258 upstream.

It could happen that either `val` or `val2` [provided from userspace] is
negative. In that case the computed frequency could get a weird value.

Fix this by checking that neither of the 2 variables is negative, and check
that the computed result is not-zero.

Fixes: e4f959390178 ("iio: imu: adis16480 switch sampling frequency attr to core support")
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/iio/imu/adis16480.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/iio/imu/adis16480.c
+++ b/drivers/iio/imu/adis16480.c
@@ -266,8 +266,11 @@ static int adis16480_set_freq(struct iio
struct adis16480 *st = iio_priv(indio_dev);
unsigned int t;

+ if (val < 0 || val2 < 0)
+ return -EINVAL;
+
t = val * 1000 + val2 / 1000;
- if (t <= 0)
+ if (t == 0)
return -EINVAL;

t = 2460000 / t;