On 22/10/2019 13:49, Colin King wrote:
> From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> Currently a multiply operation is being performed on two int values
> and the result is being assigned to a u64, presumably because the
> end result is expected to be probably larger than an int. However,
> because the multiply is an int multiply one can get overflow. Avoid
> the overflow by casting degc to a u64 to force a u64 multiply.
>
> Addresses-Coverity: ("Unintentional integer overflow")
> Fixes: fbfe1a042cfd ("drivers: thermal: tsens: Add interrupt support")
> Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> ---
> drivers/thermal/qcom/tsens-common.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
> index 03bf1b8133ea..3d7855106ecd 100644
> --- a/drivers/thermal/qcom/tsens-common.c
> +++ b/drivers/thermal/qcom/tsens-common.c
> @@ -92,7 +92,7 @@ void compute_intercept_slope(struct tsens_priv *priv, u32 *p1,
>
> static inline u32 degc_to_code(int degc, const struct tsens_sensor *s)
> {
> - u64 code = (degc * s->slope + s->offset) / SLOPE_FACTOR;
> + u64 code = ((u64)degc * s->slope + s->offset) / SLOPE_FACTOR;
- u64 code = ((u64)degc * s->slope + s->offset) / SLOPE_FACTOR;
+ u64 code = div_u64(((u64)degc * s->slope + s->offset),
SLOPE_FACTOR);
>
> pr_debug("%s: raw_code: 0x%llx, degc:%d\n", __func__, code, degc);
> return clamp_val(code, THRESHOLD_MIN_ADC_CODE, THRESHOLD_MAX_ADC_CODE);
>
--
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