[PATCH AUTOSEL 4.19 531/671] led: triggers: Fix dereferencing of null pointer

From: Sasha Levin
Date: Thu Jan 16 2020 - 13:42:34 EST


From: Oleh Kravchenko <oleg@xxxxxxxxxx>

[ Upstream commit 4016ba85880b252365d11bc7dc899450f2c73ad7 ]

Error was detected by PVS-Studio:
V522 Dereferencing of the null pointer 'led_cdev->trigger' might take place.

Fixes: 2282e125a406 ("leds: triggers: let struct led_trigger::activate() return an error code")
Signed-off-by: Oleh Kravchenko <oleg@xxxxxxxxxx>
Reviewed-by: Uwe Kleine-KÃnig <u.kleine-koenig@xxxxxxxxxxxxxx>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/leds/led-triggers.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c
index e4cb3811e82a..005b839f6eb9 100644
--- a/drivers/leds/led-triggers.c
+++ b/drivers/leds/led-triggers.c
@@ -171,11 +171,11 @@ int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trig)
trig->deactivate(led_cdev);
err_activate:

- led_cdev->trigger = NULL;
- led_cdev->trigger_data = NULL;
write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags);
list_del(&led_cdev->trig_list);
write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock, flags);
+ led_cdev->trigger = NULL;
+ led_cdev->trigger_data = NULL;
led_set_brightness(led_cdev, LED_OFF);
kfree(event);

--
2.20.1