thermal: check for invalid trip setup when registering thermal device

This patch adds an extra check in the data structure while registering
a thermal device. The check is to avoid registering zones with a number
of trips greater than zero, but with no .get_trip_temp nor .get_trip_type
callbacks. Receiving such data structure may end in wrong data access.

Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Reviewed-by: Durgadoss R <durgadoss.r@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c
index fba27c36d707..0a1bf6b032ea 100644
--- a/drivers/thermal/thermal_sys.c
+++ b/drivers/thermal/thermal_sys.c
@@ -1530,6 +1530,9 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,
         if (!ops || !ops->get_temp)
                 return ERR_PTR(-EINVAL);
 
+        if (trips > 0 && !ops->get_trip_type)
+                return ERR_PTR(-EINVAL);
+
         tz = kzalloc(sizeof(struct thermal_zone_device), GFP_KERNEL);
         if (!tz)
                 return ERR_PTR(-ENOMEM);