[PATCH 1/2] iio: fix possible buffer overflow

[Alexandre Belloni <alexandre.belloni@free-electrons.com>]

Found using smatch:
drivers/iio/industrialio-core.c:719 iio_device_add_info_mask_type() error:
buffer overflow 'iio_chan_info_postfix' 17 <= 63

It was probably never hit because the info_mask_* members are filled by using
the BIT() macro with values from the iio_chan_info_enum enum that also serve as
the index of the iio_chan_info_postfix array.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
---
 drivers/iio/industrialio-core.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index ede16aec20fb..5e7a67e53879 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -715,7 +715,8 @@ static int iio_device_add_info_mask_type(struct iio_dev *indio_dev,
 {
 	int i, ret, attrcount = 0;
 
-	for_each_set_bit(i, infomask, sizeof(infomask)*8) {
+	for_each_set_bit(i, infomask, min(sizeof(infomask)*8,
+					  ARRAY_SIZE(iio_chan_info_postfix))) {
 		ret = __iio_add_chan_devattr(iio_chan_info_postfix[i],
 					     chan,
 					     &iio_read_channel_info,
-- 
1.9.1