From: Hans Verkuil <hverkuil+cisco@kernel.org>
Date: Sat, 6 Sep 2025 10:11:21 +0000 (+0200)
Subject: media: vivid: fix disappearing <Vendor Command With ID> messages
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4bd8a6147645480d550242ff816b4c7ba160e5b7;p=thirdparty%2Fkernel%2Fstable.git

media: vivid: fix disappearing <Vendor Command With ID> messages

The vivid driver supports the <Vendor Command With ID> message,
but if the Vendor ID of the received message didn't match the Vendor ID
of the CEC Adapter, then it ignores it (good) and returns 0 (bad).

It should return -ENOMSG to indicate that other followers should be
asked to handle it. Return code 0 means that the driver handled it,
which is wrong in this case.

As a result, userspace followers never get the chance to process such a
message.

Refactor the code a bit to have the function return -ENOMSG at the end,
drop the default case, and ensure that the message handlers return 0.

That way 0 is only returned if the message is actually handled in the
vivid_received() function.

Fixes: 812765cd6954 ("media: vivid: add <Vendor Command With ID> support")
Cc: stable@vger.kernel.org
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
---

diff --git a/drivers/media/test-drivers/vivid/vivid-cec.c b/drivers/media/test-drivers/vivid/vivid-cec.c
index 356a988dd6a1..2d15fdd5d999 100644
--- a/drivers/media/test-drivers/vivid/vivid-cec.c
+++ b/drivers/media/test-drivers/vivid/vivid-cec.c
@@ -327,7 +327,7 @@ static int vivid_received(struct cec_adapter *adap, struct cec_msg *msg)
 		char osd[14];
 
 		if (!cec_is_sink(adap))
-			return -ENOMSG;
+			break;
 		cec_ops_set_osd_string(msg, &disp_ctl, osd);
 		switch (disp_ctl) {
 		case CEC_OP_DISP_CTL_DEFAULT:
@@ -348,7 +348,7 @@ static int vivid_received(struct cec_adapter *adap, struct cec_msg *msg)
 			cec_transmit_msg(adap, &reply, false);
 			break;
 		}
-		break;
+		return 0;
 	}
 	case CEC_MSG_VENDOR_COMMAND_WITH_ID: {
 		u32 vendor_id;
@@ -379,7 +379,7 @@ static int vivid_received(struct cec_adapter *adap, struct cec_msg *msg)
 		if (size == 1) {
 			// Ignore even op values
 			if (!(vendor_cmd[0] & 1))
-				break;
+				return 0;
 			reply.len = msg->len;
 			memcpy(reply.msg + 1, msg->msg + 1, msg->len - 1);
 			reply.msg[msg->len - 1]++;
@@ -388,12 +388,10 @@ static int vivid_received(struct cec_adapter *adap, struct cec_msg *msg)
 					      CEC_OP_ABORT_INVALID_OP);
 		}
 		cec_transmit_msg(adap, &reply, false);
-		break;
+		return 0;
 	}
-	default:
-		return -ENOMSG;
 	}
-	return 0;
+	return -ENOMSG;
 }
 
 static const struct cec_adap_ops vivid_cec_adap_ops = {