Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

power: supply: max17040: handle missing status supplier

MAX17040 does not report charger state itself, so the driver forwards POWER_SUPPLY_PROP_STATUS to a supplier power supply. If no supplier is registered, power_supply_get_property_from_supplier() returns -ENODEV and leaves the output value untouched.

max17040_get_property() currently ignores that error and returns success, so userspace can read an uninitialized status value from the battery power supply. This happens on systems that use the fuel gauge without a charger supplier relationship in firmware.

Return POWER_SUPPLY_STATUS_UNKNOWN when no supplier provides STATUS, and propagate other supplier lookup errors.