thermal: core: Fix TZ_GET_TRIP NULL pointer dereference

commit 5838a14832d447990827d85e90afe17e6fb9c175 upstream.

Do not call get_trip_hyst() from thermal_genl_cmd_tz_get_trip() if
the thermal zone does not define one.

Fixes: 1ce50e7d408e ("thermal: core: genetlink support for events/cmd/sampling")
Signed-off-by: Nicolas Cavallari <nicolas.cavallari@green-communications.fr>
Cc: 5.10+ <stable@vger.kernel.org> # 5.10+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/thermal/thermal_netlink.c b/drivers/thermal/thermal_netlink.c
index 1234dbe..41c8d47 100644 (file)
--- a/drivers/thermal/thermal_netlink.c
+++ b/drivers/thermal/thermal_netlink.c
@@ -418,11 +418,12 @@ static int thermal_genl_cmd_tz_get_trip(struct param *p)
        for (i = 0; i < tz->trips; i++) {
 
                enum thermal_trip_type type;
-               int temp, hyst;
+               int temp, hyst = 0;
 
                tz->ops->get_trip_type(tz, i, &type);
                tz->ops->get_trip_temp(tz, i, &temp);
-               tz->ops->get_trip_hyst(tz, i, &hyst);
+               if (tz->ops->get_trip_hyst)
+                       tz->ops->get_trip_hyst(tz, i, &hyst);
 
                if (nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_TRIP_ID, i) ||
                    nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_TRIP_TYPE, type) ||