can: j1939: transport: j1939_simple_recv(): ignore local J1939 messag…

…es send not by J1939 stack

In current J1939 stack implementation, we process all locally send
messages as own messages. Even if it was send by CAN_RAW socket.

To reproduce it use following commands:
testj1939 -P -r can0:0x80 &
cansend can0 18238040#0123

This step will trigger false positive not critical warning:
j1939_simple_recv: Received already invalidated message

With this patch we add additional check to make sure, related skb is own
echo message.

Fixes: 9d71dd0 ("can: add support of SAE J1939 protocol")
Signed-off-by: Oleksij Rempel <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Marc Kleine-Budde <[email protected]>

net/can/j1939/socket.c

@@ -398,6 +398,7 @@ static int j1939_sk_init(struct sock *sk)
 	spin_lock_init(&jsk->sk_session_queue_lock);
 	INIT_LIST_HEAD(&jsk->sk_session_queue);
 	sk->sk_destruct = j1939_sk_sock_destruct;
+	sk->sk_protocol = CAN_J1939;
 
 	return 0;
 }

net/can/j1939/transport.c

@@ -2017,6 +2017,10 @@ void j1939_simple_recv(struct j1939_priv *priv, struct sk_buff *skb)
 	if (!skb->sk)
 		return;
 
+	if (skb->sk->sk_family != AF_CAN ||
+	    skb->sk->sk_protocol != CAN_J1939)
+		return;
+
 	j1939_session_list_lock(priv);
 	session = j1939_session_get_simple(priv, skb);
 	j1939_session_list_unlock(priv);