leds: lp5523: fix a missing check of return value of lp55xx_read

kengiter · jacek-anaszewski · commit 248b57015f35 · 2019-01-17T22:27:39.000+01:00
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 &lt;kjlu@umn.edu&gt;
Signed-off-by: Jacek Anaszewski &lt;jacek.anaszewski@gmail.com&gt;
diff --git 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) {
