[PATCH] iio: ad5755: fix off-by-one on devnr limit check

From: Colin King
Date: Mon Jul 25 2016 - 18:41:34 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

The comparison for devnr limits is off-by-one, the current check
allows 0 to AD5755_NUM_CHANNELS and the limit should be in fact
0 to AD5755_NUM_CHANNELS - 1. This can lead to an out of bounds
write to pdata->dac[devnr]. Fix this by replacing > with >= on the
comparison.

Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
drivers/iio/dac/ad5755.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/dac/ad5755.c b/drivers/iio/dac/ad5755.c
index 0fde593..5f79682 100644
--- a/drivers/iio/dac/ad5755.c
+++ b/drivers/iio/dac/ad5755.c
@@ -655,7 +655,7 @@ static struct ad5755_platform_data *ad5755_parse_dt(struct device *dev)

devnr = 0;
for_each_child_of_node(np, pp) {
- if (devnr > AD5755_NUM_CHANNELS) {
+ if (devnr >= AD5755_NUM_CHANNELS) {
dev_err(dev,
"There is to many channels defined in DT\n");
goto error_out;
--
2.8.1