diff --git a/net/can/isotp.c b/net/can/isotp.c
index 9149e8d8aefc..d2a430b6a13b 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -887,7 +887,7 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 
 	if (!size || size > MAX_MSG_LENGTH) {
 		err = -EINVAL;
-		goto err_out;
+		goto err_out_drop;
 	}
 
 	/* take care of a potential SF_DL ESC offset for TX_DL > 8 */
@@ -897,24 +897,24 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 	if ((so->opt.flags & CAN_ISOTP_SF_BROADCAST) &&
 	    (size > so->tx.ll_dl - SF_PCI_SZ4 - ae - off)) {
 		err = -EINVAL;
-		goto err_out;
+		goto err_out_drop;
 	}
 
 	err = memcpy_from_msg(so->tx.buf, msg, size);
 	if (err < 0)
-		goto err_out;
+		goto err_out_drop;
 
 	dev = dev_get_by_index(sock_net(sk), so->ifindex);
 	if (!dev) {
 		err = -ENXIO;
-		goto err_out;
+		goto err_out_drop;
 	}
 
 	skb = sock_alloc_send_skb(sk, so->ll.mtu + sizeof(struct can_skb_priv),
 				  msg->msg_flags & MSG_DONTWAIT, &err);
 	if (!skb) {
 		dev_put(dev);
-		goto err_out;
+		goto err_out_drop;
 	}
 
 	can_skb_reserve(skb);
@@ -976,7 +976,7 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 	if (err) {
 		pr_notice_once("can-isotp: %s: can_send_ret %pe\n",
 			       __func__, ERR_PTR(err));
-		goto err_out;
+		goto err_out_drop;
 	}
 
 	if (wait_tx_done) {
@@ -989,6 +989,9 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 
 	return size;
 
+err_out_drop:
+	/* drop this PDU and unlock a potential wait queue */
+	old_state = ISOTP_IDLE;
 err_out:
 	so->tx.state = old_state;
 	if (so->tx.state == ISOTP_IDLE)