[PATCH] iio: adc: mcp3911: Fix out of bounds access of array mcp3911_osr_table

From: Colin Ian King
Date: Wed Oct 12 2022 - 09:42:54 EST


Currently the for-loop is using the size of the array mcp3911_osr_table
as the upper bounds which is 0..31 which is causing an out of bounds
access to the array at indexes 8..31. Fix this using the ARRAY_SIZE
macro to get the size of the array in elements rather than bytes.

Fixes: 6d965885f4ea ("iio: adc: mcp3911: add support for oversampling ratio")
Signed-off-by: Colin Ian King <colin.i.king@xxxxxxxxx>
---
drivers/iio/adc/mcp3911.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/adc/mcp3911.c b/drivers/iio/adc/mcp3911.c
index b35fd2c9c3c0..015a9ffdb26a 100644
--- a/drivers/iio/adc/mcp3911.c
+++ b/drivers/iio/adc/mcp3911.c
@@ -248,7 +248,7 @@ static int mcp3911_write_raw(struct iio_dev *indio_dev,
break;

case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
- for (int i = 0; i < sizeof(mcp3911_osr_table); i++) {
+ for (int i = 0; i < ARRAY_SIZE(mcp3911_osr_table); i++) {
if (val == mcp3911_osr_table[i]) {
val = FIELD_PREP(MCP3911_CONFIG_OSR, i);
ret = mcp3911_update(adc, MCP3911_REG_CONFIG, MCP3911_CONFIG_OSR,
--
2.37.3