[PATCH 4.9 043/129] leds: leds-lp5562 allow firmware files up to the maximum length

From: Greg Kroah-Hartman
Date: Thu Oct 03 2019 - 12:02:12 EST


From: Nick Stoughton <nstoughton@xxxxxxxxxxxx>

[ Upstream commit ed2abfebb041473092b41527903f93390d38afa7 ]

Firmware files are in ASCII, using 2 hex characters per byte. The
maximum length of a firmware string is therefore

16 (commands) * 2 (bytes per command) * 2 (characters per byte) = 64

Fixes: ff45262a85db ("leds: add new LP5562 LED driver")
Signed-off-by: Nick Stoughton <nstoughton@xxxxxxxxxxxx>
Acked-by: Pavel Machek <pavel@xxxxxx>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/leds/leds-lp5562.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/leds/leds-lp5562.c b/drivers/leds/leds-lp5562.c
index b75333803a637..9f5e4d04efad5 100644
--- a/drivers/leds/leds-lp5562.c
+++ b/drivers/leds/leds-lp5562.c
@@ -263,7 +263,11 @@ static void lp5562_firmware_loaded(struct lp55xx_chip *chip)
{
const struct firmware *fw = chip->fw;

- if (fw->size > LP5562_PROGRAM_LENGTH) {
+ /*
+ * the firmware is encoded in ascii hex character, with 2 chars
+ * per byte
+ */
+ if (fw->size > (LP5562_PROGRAM_LENGTH * 2)) {
dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
fw->size);
return;
--
2.20.1