[PATCH 4.20 111/145] media: cec-pin: fix broken tx_ignore_nack_until_eom error injection

[Greg Kroah-Hartman]

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

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

From: Hans Verkuil <hverkuil@xxxxxxxxx>

commit ac791f19a273a7fe254a7596f193af6534582a9f upstream.

If the tx_ignore_nack_until_eom error injection was activated,
then tx_nacked was never set instead of setting it when the last
byte of the message was transmitted.

As a result the transmit was marked as OK, when it should have
been NACKed.

Modify the condition so that it always sets tx_nacked when the
last byte of the message was transmitted.

Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>      # for v4.17 and up
Signed-off-by: Hans Verkuil <hansverk@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/media/cec/cec-pin.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/media/cec/cec-pin.c
+++ b/drivers/media/cec/cec-pin.c
@@ -601,8 +601,9 @@ static void cec_pin_tx_states(struct cec
 			break;
 		/* Was the message ACKed? */
 		ack = cec_msg_is_broadcast(&pin->tx_msg) ? v : !v;
-		if (!ack && !pin->tx_ignore_nack_until_eom &&
-		    pin->tx_bit / 10 < pin->tx_msg.len && !pin->tx_post_eom) {
+		if (!ack && (!pin->tx_ignore_nack_until_eom ||
+		    pin->tx_bit / 10 == pin->tx_msg.len - 1) &&
+		    !pin->tx_post_eom) {
 			/*
 			 * Note: the CEC spec is ambiguous regarding
 			 * what action to take when a NACK appears