power: supply: max17042: avoid overflow when determining health

commit 9a44949 upstream.

If vmax has the default value of INT_MAX (e.g. because not specified in
DT), battery health is reported as over-voltage. This is because adding
any value to vmax (the vmax tolerance in this case) causes it to wrap
around, making it negative and smaller than the measured battery
voltage.

Avoid that by using size_add().

Fixes: edd4ab0 ("power: max17042_battery: add HEALTH and TEMP_* properties support")
Cc: stable@vger.kernel.org
Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://patch.msgid.link/20260302-max77759-fg-v3-6-3c5f01dbda23@linaro.org
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: andred

drivers/power/supply/max17042_battery.c

@@ -199,7 +199,7 @@ static int max17042_get_battery_health(struct max17042_chip *chip, int *health)
 		goto out;
 	}
 
-	if (vbatt > chip->pdata->vmax + MAX17042_VMAX_TOLERANCE) {
+	if (vbatt > size_add(chip->pdata->vmax, MAX17042_VMAX_TOLERANCE)) {
 		*health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
 		goto out;
 	}