[bug report] thermal/drivers/mediatek: Add the Low Voltage Thermal Sensor driver

[bug report] thermal/drivers/mediatek: Add the Low Voltage Thermal Sensor driver

[Dan Carpenter]

Hello Balsam CHIHI,

The patch f5f633b18234: "thermal/drivers/mediatek: Add the Low
Voltage Thermal Sensor driver" from Feb 9, 2023, leads to the
following Smatch static checker warning:

	drivers/thermal/mediatek/lvts_thermal.c:562 lvts_calibration_init()
	warn: not copying enough bytes for '&lvts_ctrl->calibration[i]' (4 vs 2 bytes)

drivers/thermal/mediatek/lvts_thermal.c
    555 static int lvts_calibration_init(struct device *dev, struct lvts_ctrl *lvts_ctrl,
    556                                         const struct lvts_ctrl_data *lvts_ctrl_data,
    557                                         u8 *efuse_calibration)
    558 {
    559         int i;
    560 
    561         for (i = 0; i < lvts_ctrl_data->num_lvts_sensor; i++)
--> 562                 memcpy(&lvts_ctrl->calibration[i],
    563                        efuse_calibration + lvts_ctrl_data->cal_offset[i], 2);
                                                                                  ^
This is copying an array of known ints to a u32 array.  It should copy
sizeof(int) instead of 2.  It only works because the data you're on
little endian and the data is small.

    564 
    565         return 0;
    566 }

regards,
dan carpenter

Re: [bug report] thermal/drivers/mediatek: Add the Low Voltage Thermal Sensor driver

[Balsam CHIHI]

On Mon, Feb 27, 2023 at 12:26 PM Dan Carpenter <error27@gmail.com> wrote:
>
> Hello Balsam CHIHI,
>
> The patch f5f633b18234: "thermal/drivers/mediatek: Add the Low
> Voltage Thermal Sensor driver" from Feb 9, 2023, leads to the
> following Smatch static checker warning:
>
>         drivers/thermal/mediatek/lvts_thermal.c:562 lvts_calibration_init()
>         warn: not copying enough bytes for '&lvts_ctrl->calibration[i]' (4 vs 2 bytes)
>
> drivers/thermal/mediatek/lvts_thermal.c
>     555 static int lvts_calibration_init(struct device *dev, struct lvts_ctrl *lvts_ctrl,
>     556                                         const struct lvts_ctrl_data *lvts_ctrl_data,
>     557                                         u8 *efuse_calibration)
>     558 {
>     559         int i;
>     560
>     561         for (i = 0; i < lvts_ctrl_data->num_lvts_sensor; i++)
> --> 562                 memcpy(&lvts_ctrl->calibration[i],
>     563                        efuse_calibration + lvts_ctrl_data->cal_offset[i], 2);
>                                                                                   ^
> This is copying an array of known ints to a u32 array.  It should copy
> sizeof(int) instead of 2.  It only works because the data you're on
> little endian and the data is small.
>
>     564
>     565         return 0;
>     566 }
>
> regards,
> dan carpenter

Hello Dan Carpenter,

Thank you for reporting this bug.
I will create a patch to fix it ASAP.

Best regards,
Balsam