From: Vasileios Amoiridis <vassilisamir@xxxxxxxxx>
commit fdd478c3ae98c3f13628e110dce9b6cfb0d9b3c8 upstream.
There are cases in the compensate functions of the driver that
there could be overflows of variables due to bit shifting ops.
These implications were initially discussed here [1] and they
were mentioned in log message of Commit 1b3bd8592780 ("iio:
chemical: Add support for Bosch BME680 sensor").
[1]: https://lore.kernel.org/linux-iio/20180728114028.3c1bbe81@archlinux/
Fixes: 1b3bd8592780 ("iio: chemical: Add support for Bosch BME680 sensor")
Signed-off-by: Vasileios Amoiridis <vassilisamir@xxxxxxxxx>
Link: https://lore.kernel.org/r/20240606212313.207550-4-vassilisamir@xxxxxxxxx
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/iio/chemical/bme680_core.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
--- a/drivers/iio/chemical/bme680_core.c
+++ b/drivers/iio/chemical/bme680_core.c
@@ -348,10 +348,10 @@ static s16 bme680_compensate_temp(struct
if (!calib->par_t2)
bme680_read_calib(data, calib);
- var1 = (adc_temp >> 3) - (calib->par_t1 << 1);
+ var1 = (adc_temp >> 3) - ((s32)calib->par_t1 << 1);
var2 = (var1 * calib->par_t2) >> 11;
var3 = ((var1 >> 1) * (var1 >> 1)) >> 12;
- var3 = (var3 * (calib->par_t3 << 4)) >> 14;
+ var3 = (var3 * ((s32)calib->par_t3 << 4)) >> 14;
data->t_fine = var2 + var3;
calc_temp = (data->t_fine * 5 + 128) >> 8;
@@ -374,9 +374,9 @@ static u32 bme680_compensate_press(struc
var1 = (data->t_fine >> 1) - 64000;
var2 = ((((var1 >> 2) * (var1 >> 2)) >> 11) * calib->par_p6) >> 2;
var2 = var2 + (var1 * calib->par_p5 << 1);
- var2 = (var2 >> 2) + (calib->par_p4 << 16);
+ var2 = (var2 >> 2) + ((s32)calib->par_p4 << 16);
var1 = (((((var1 >> 2) * (var1 >> 2)) >> 13) *
- (calib->par_p3 << 5)) >> 3) +
+ ((s32)calib->par_p3 << 5)) >> 3) +
((calib->par_p2 * var1) >> 1);
var1 = var1 >> 18;
var1 = ((32768 + var1) * calib->par_p1) >> 15;
@@ -394,7 +394,7 @@ static u32 bme680_compensate_press(struc
var3 = ((press_comp >> 8) * (press_comp >> 8) *
(press_comp >> 8) * calib->par_p10) >> 17;
- press_comp += (var1 + var2 + var3 + (calib->par_p7 << 7)) >> 4;
+ press_comp += (var1 + var2 + var3 + ((s32)calib->par_p7 << 7)) >> 4;
return press_comp;
}
@@ -420,7 +420,7 @@ static u32 bme680_compensate_humid(struc
(((temp_scaled * ((temp_scaled * calib->par_h5) / 100))
>> 6) / 100) + (1 << 14))) >> 10;
var3 = var1 * var2;
- var4 = calib->par_h6 << 7;
+ var4 = (s32)calib->par_h6 << 7;
var4 = (var4 + ((temp_scaled * calib->par_h7) / 100)) >> 4;
var5 = ((var3 >> 14) * (var3 >> 14)) >> 10;
var6 = (var4 * var5) >> 1;
Patches currently in stable-queue which might be from vassilisamir@xxxxxxxxx are
queue-4.19/iio-chemical-bme680-fix-calibration-data-variable.patch
queue-4.19/iio-chemical-bme680-fix-sensor-data-read-operation.patch
queue-4.19/iio-chemical-bme680-fix-overflows-in-compensate-functions.patch
queue-4.19/iio-chemical-bme680-fix-pressure-value-output.patch
