thermal: Exynos: Fix NULL pointer dereference in exynos_unregister_thermal()

exynos_unregister_thermal() is functional only when 'th_zone' is not
NULL (ensured by the NULL checks). However, in the event it is NULL, it
gets dereferenced in the for loop. This patch fixes this issue.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/thermal/exynos_thermal.c b/drivers/thermal/exynos_thermal.c
index e84acde9e0bf..fd03e8581afc 100644
--- a/drivers/thermal/exynos_thermal.c
+++ b/drivers/thermal/exynos_thermal.c
@@ -475,11 +475,14 @@ static void exynos_unregister_thermal(void)
 {
         int i;
 
-        if (th_zone && th_zone->therm_dev)
+        if (!th_zone)
+                return;
+
+        if (th_zone->therm_dev)
                 thermal_zone_device_unregister(th_zone->therm_dev);
 
         for (i = 0; i < th_zone->cool_dev_size; i++) {
-                if (th_zone && th_zone->cool_dev[i])
+                if (th_zone->cool_dev[i])
                         cpufreq_cooling_unregister(th_zone->cool_dev[i]);
         }