2023-01-30 18:48:08

by Rafael J. Wysocki

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

From: Rafael J. Wysocki <[email protected]>

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 <[email protected]>
---

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))

2023-01-31 15:40:27

by Daniel Lezcano

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

On 30/01/2023 19:47, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <[email protected]>
>
> 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 <[email protected]>
> ---

Acked-by: Daniel Lezcano <[email protected]>


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