diff --git a/net/can/isotp.c b/net/can/isotp.c
index f02b5d3e47335..d1c6f206f4295 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -948,21 +948,18 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 	if (!so->bound || so->tx.state == ISOTP_SHUTDOWN)
 		return -EADDRNOTAVAIL;
 
-wait_free_buffer:
-	/* we do not support multiple buffers - for now */
-	if (wq_has_sleeper(&so->wait) && (msg->msg_flags & MSG_DONTWAIT))
-		return -EAGAIN;
+	while (cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SENDING) != ISOTP_IDLE) {
+		/* we do not support multiple buffers - for now */
+		if (msg->msg_flags & MSG_DONTWAIT)
+			return -EAGAIN;
 
-	/* wait for complete transmission of current pdu */
-	err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
-	if (err)
-		goto err_event_drop;
-
-	if (cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SENDING) != ISOTP_IDLE) {
 		if (so->tx.state == ISOTP_SHUTDOWN)
 			return -EADDRNOTAVAIL;
 
-		goto wait_free_buffer;
+		/* wait for complete transmission of current pdu */
+		err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+		if (err)
+			goto err_event_drop;
 	}
 
 	/* PDU size > default => try max_pdu_size */