[PATCH 4.14 20/40] media: s5p_cec: limit msg.len to CEC_MAX_MSG_SIZE

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Hans Verkuil <hverkuil-cisco@xs4all.nl>

[ Upstream commit 93f65ce036863893c164ca410938e0968964b26c ]

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@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/media/platform/s5p-cec/s5p_cec.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/media/platform/s5p-cec/s5p_cec.c b/drivers/media/platform/s5p-cec/s5p_cec.c
index 3032247c63a5..554c8f2b60b8 100644
--- a/drivers/media/platform/s5p-cec/s5p_cec.c
+++ b/drivers/media/platform/s5p-cec/s5p_cec.c
@@ -116,6 +116,8 @@ static irqreturn_t s5p_cec_irq_handler(int irq, void *priv)
 				dev_dbg(cec->dev, "Buffer overrun (worker did not process previous message)\n");
 			cec->rx = STATE_BUSY;
 			cec->msg.len = status >> 24;
+			if (cec->msg.len > CEC_MAX_MSG_SIZE)
+				cec->msg.len = CEC_MAX_MSG_SIZE;
 			cec->msg.rx_status = CEC_RX_STATUS_OK;
 			s5p_cec_get_rx_buf(cec, cec->msg.len,
 					cec->msg.msg);
-- 
2.35.1