1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index 777439f48c14..111a91dc6b79 100644
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -334,8 +334,18 @@ static int pwm_fan_probe(struct platform_device *pdev)
 
 	ctx->pwm_value = MAX_PWM;
 
-	/* Set duty cycle to maximum allowed and enable PWM output */
 	pwm_init_state(ctx->pwm, &state);
+	/*
+	 * __set_pwm assumes that MAX_PWM * (period - 1) fits into an unsigned
+	 * long. Check this here to prevent the fan running at a too low
+	 * frequency.
+	 */
+	if (state.period > ULONG_MAX / MAX_PWM + 1) {
+		dev_err(dev, "Configured period too big\n");
+		return -EINVAL;
+	}
+
+	/* Set duty cycle to maximum allowed and enable PWM output */
 	state.duty_cycle = ctx->pwm->args.period - 1;
 	state.enabled = true;