[PATCH v2 4/4] thermal: intel: int340x: Improve int340x_thermal_set_trip_temp()

Rafael J. Wysocki
2023-01-30T18:48:05Z

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Instead of using snprintf() to populate the ACPI object name in
int340x_thermal_set_trip_temp(), use an appropriate initializer
and make the function fail if its trip argument is greater than 9,
because ACPI object names can only be 4 characters long and it does
not make sense to even try to evaluate objects with longer names (that
argument is guaranteed to be non-negative, because it comes from the
thermal code that will not pass negative trip numbers to zone
callbacks).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

v1 -> v2: New patch in v2

---
drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

Index: linux-pm/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
===================================================================
--- linux-pm.orig/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
+++ linux-pm/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
@@ -42,10 +42,12 @@ static int int340x_thermal_set_trip_temp
int trip, int temp)
{
struct int34x_thermal_zone *d = zone->devdata;
+ char name[] = {'P', 'A', 'T', '0' + trip, '\0'};
acpi_status status;
- char name[10];

- snprintf(name, sizeof(name), "PAT%d", trip);
+ if (trip > 9)
+ return -EINVAL;
+
status = acpi_execute_simple_method(d->adev->handle, name,
millicelsius_to_deci_kelvin(temp));
if (ACPI_FAILURE(status))