4.19-stable review patch. If anyone has any objections, please let me know.
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From: Vasileios Amoiridis vassilisamir@gmail.com
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@gmail.com Link: https://lore.kernel.org/r/20240606212313.207550-4-vassilisamir@gmail.com Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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;