[PATCH 4/9] thermal/drivers/mediatek/lvts_thermal: guard against efuse data buffer overflow

Nicolas Pitre
2024-01-11T22:30:33Z

From: Nicolas Pitre <npitre@baylibre.com>

We don't want to silently fetch garbage past the actual buffer.

Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
---
drivers/thermal/mediatek/lvts_thermal.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/thermal/mediatek/lvts_thermal.c b/drivers/thermal/mediatek/lvts_thermal.c
index 2c346ea7c6..ed1888fb24 100644
--- a/drivers/thermal/mediatek/lvts_thermal.c
+++ b/drivers/thermal/mediatek/lvts_thermal.c
@@ -674,7 +674,8 @@ static int lvts_sensor_init(struct device *dev, struct lvts_ctrl *lvts_ctrl,
*/
static int lvts_calibration_init(struct device *dev, struct lvts_ctrl *lvts_ctrl,
const struct lvts_ctrl_data *lvts_ctrl_data,
- u8 *efuse_calibration)
+ u8 *efuse_calibration,
+ size_t calib_len)
{
int i;

@@ -682,6 +683,11 @@ static int lvts_calibration_init(struct device *dev, struct lvts_ctrl *lvts_ctrl
const struct lvts_sensor_data *sensor =
&lvts_ctrl_data->lvts_sensor[i];

+ if (sensor->cal_offsets[0] >= calib_len ||
+ sensor->cal_offsets[1] >= calib_len ||
+ sensor->cal_offsets[2] >= calib_len)
+ return -EINVAL;
+
lvts_ctrl->calibration[i] =
(efuse_calibration[sensor->cal_offsets[0]] << 0) +
(efuse_calibration[sensor->cal_offsets[1]] << 8) +
@@ -791,7 +797,8 @@ static int lvts_ctrl_init(struct device *dev, struct lvts_domain *lvts_td,

ret = lvts_calibration_init(dev, &lvts_ctrl[i],
&lvts_data->lvts_ctrl[i],
- lvts_td->calib);
+ lvts_td->calib,
+ lvts_td->calib_len);
if (ret)
return ret;

--
2.42.0