[PATCH AUTOSEL 4.19 2/6] media: cros-ec-cec: limit msg.len to CEC_MAX_MSG_SIZE

From: Sasha Levin
Date: Tue Nov 01 2022 - 07:38:45 EST


From: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>

[ Upstream commit 2dc73b48665411a08c4e5f0f823dea8510761603 ]

I expect that the hardware will have limited this to 16, but just in
case it hasn't, check for this corner case.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/media/platform/cros-ec-cec/cros-ec-cec.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/media/platform/cros-ec-cec/cros-ec-cec.c b/drivers/media/platform/cros-ec-cec/cros-ec-cec.c
index 7bc4d8a9af28..1f35770245d1 100644
--- a/drivers/media/platform/cros-ec-cec/cros-ec-cec.c
+++ b/drivers/media/platform/cros-ec-cec/cros-ec-cec.c
@@ -44,6 +44,8 @@ static void handle_cec_message(struct cros_ec_cec *cros_ec_cec)
uint8_t *cec_message = cros_ec->event_data.data.cec_message;
unsigned int len = cros_ec->event_size;

+ if (len > CEC_MAX_MSG_SIZE)
+ len = CEC_MAX_MSG_SIZE;
cros_ec_cec->rx_msg.len = len;
memcpy(cros_ec_cec->rx_msg.msg, cec_message, len);

--
2.35.1