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    Subject[87/87] hwmon: (sht15) Fix integer overflow in humidity calculation
    2.6.37-stable review patch.  If anyone has any objections, please let us know.

    ------------------

    From: Vivien Didelot <vivien.didelot@savoirfairelinux.com>

    commit ccd32e735de7a941906e093f8dca924bb05c5794 upstream.

    An integer overflow occurs in the calculation of RHlinear when the
    relative humidity is greater than around 30%. The consequence is a subtle
    (but noticeable) error in the resulting humidity measurement.

    Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
    Signed-off-by: Jean Delvare <khali@linux-fr.org>
    Cc: Jonathan Cameron <jic23@cam.ac.uk>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    drivers/hwmon/sht15.c | 4 ++--
    1 file changed, 2 insertions(+), 2 deletions(-)

    --- a/drivers/hwmon/sht15.c
    +++ b/drivers/hwmon/sht15.c
    @@ -333,11 +333,11 @@ static inline int sht15_calc_humid(struc

    const int c1 = -4;
    const int c2 = 40500; /* x 10 ^ -6 */
    - const int c3 = -2800; /* x10 ^ -9 */
    + const int c3 = -28; /* x 10 ^ -7 */

    RHlinear = c1*1000
    + c2 * data->val_humid/1000
    - + (data->val_humid * data->val_humid * c3)/1000000;
    + + (data->val_humid * data->val_humid * c3) / 10000;
    return (temp - 25000) * (10000 + 80 * data->val_humid)
    / 1000000 + RHlinear;
    }



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