[PATCH][next] iio: tsl2x7x/tsl2772: avoid potential division by zero

* [PATCH][next] iio: tsl2x7x/tsl2772: avoid potential division by zero
@ 2018-05-30 18:19 Colin King
  2018-05-31  9:28 ` Brian Masney
  0 siblings, 1 reply; 3+ messages in thread
From: Colin King @ 2018-05-30 18:19 UTC (permalink / raw)
  To: Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
	Peter Meerwald-Stadler, Brian Masney, linux-iio
  Cc: kernel-janitors, linux-kernel

From: Colin Ian King <colin.king@canonical.com>

It may be possible for tsl2772_get_lux to return a zero lux value
and hence a division by zero can occur when lux_val is zero. Check
for this case and return -ERANGE to avoid the division by zero.

Detected by CoverityScan, CID#1469484 ("Division or modulo by zero")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/iio/light/tsl2772.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iio/light/tsl2772.c b/drivers/iio/light/tsl2772.c
index 34d42a2504c9..df5b2a0da96c 100644
--- a/drivers/iio/light/tsl2772.c
+++ b/drivers/iio/light/tsl2772.c
@@ -582,6 +582,8 @@ static int tsl2772_als_calibrate(struct iio_dev *indio_dev)
 			"%s: failed to get lux\n", __func__);
 		return lux_val;
 	}
+	if (lux_val == 0)
+		return -ERANGE;
 
 	ret = (chip->settings.als_cal_target * chip->settings.als_gain_trim) /
 			lux_val;
-- 
2.17.0

^ permalink raw reply related	[flat|nested] 3+ messages in thread