[PATCH 4.9 24/63] leds: lp5523: fix a missing check of return value of lp55xx_read

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit 248b57015f35c94d4eae2fdd8c6febf5cd703900 ]

When lp55xx_read() fails, "status" is an uninitialized variable and thus
may contain random value; using it leads to undefined behaviors.

The fix inserts a check for the return value of lp55xx_read: if it
fails, returns with its error code.

Signed-off-by: Kangjie Lu <kjlu@xxxxxxx>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/leds/leds-lp5523.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/leds/leds-lp5523.c b/drivers/leds/leds-lp5523.c
index c5b30f06218a3..44ceed7ac3c5b 100644
--- a/drivers/leds/leds-lp5523.c
+++ b/drivers/leds/leds-lp5523.c
@@ -318,7 +318,9 @@ static int lp5523_init_program_engine(struct lp55xx_chip *chip)
 
 	/* Let the programs run for couple of ms and check the engine status */
 	usleep_range(3000, 6000);
-	lp55xx_read(chip, LP5523_REG_STATUS, &status);
+	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
+	if (ret)
+		return ret;
 	status &= LP5523_ENG_STATUS_MASK;
 
 	if (status != LP5523_ENG_STATUS_MASK) {
-- 
2.19.1