1 files changed, 29 insertions, 36 deletions

diff --git a/net/can/isotp.c b/net/can/isotp.c
index dae421f6c901..fc81d77724a1 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -140,7 +140,7 @@ struct isotp_sock {
 	canid_t rxid;
 	ktime_t tx_gap;
 	ktime_t lastrxcf_tstamp;
-	struct hrtimer rxtimer, txtimer;
+	struct hrtimer rxtimer, txtimer, txfrtimer;
 	struct can_isotp_options opt;
 	struct can_isotp_fc_options rxfc, txfc;
 	struct can_isotp_ll_options ll;
@@ -871,7 +871,7 @@ static void isotp_rcv_echo(struct sk_buff *skb, void *data)
 	}
 
 	/* start timer to send next consecutive frame with correct delay */
-	hrtimer_start(&so->txtimer, so->tx_gap, HRTIMER_MODE_REL_SOFT);
+	hrtimer_start(&so->txfrtimer, so->tx_gap, HRTIMER_MODE_REL_SOFT);
 }
 
 static enum hrtimer_restart isotp_tx_timer_handler(struct hrtimer *hrtimer)
@@ -879,49 +879,39 @@ static enum hrtimer_restart isotp_tx_timer_handler(struct hrtimer *hrtimer)
 	struct isotp_sock *so = container_of(hrtimer, struct isotp_sock,
 					     txtimer);
 	struct sock *sk = &so->sk;
-	enum hrtimer_restart restart = HRTIMER_NORESTART;
 
-	switch (so->tx.state) {
-	case ISOTP_SENDING:
+	/* don't handle timeouts in IDLE state */
+	if (so->tx.state == ISOTP_IDLE)
+		return HRTIMER_NORESTART;
 
-		/* cfecho should be consumed by isotp_rcv_echo() here */
-		if (!so->cfecho) {
-			/* start timeout for unlikely lost echo skb */
-			hrtimer_set_expires(&so->txtimer,
-					    ktime_add(ktime_get(),
-						      ktime_set(ISOTP_ECHO_TIMEOUT, 0)));
-			restart = HRTIMER_RESTART;
+	/* we did not get any flow control or echo frame in time */
 
-			/* push out the next consecutive frame */
-			isotp_send_cframe(so);
-			break;
-		}
-
-		/* cfecho has not been cleared in isotp_rcv_echo() */
-		pr_notice_once("can-isotp: cfecho %08X timeout\n", so->cfecho);
-		fallthrough;
+	/* report 'communication error on send' */
+	sk->sk_err = ECOMM;
+	if (!sock_flag(sk, SOCK_DEAD))
+		sk_error_report(sk);
 
-	case ISOTP_WAIT_FC:
-	case ISOTP_WAIT_FIRST_FC:
+	/* reset tx state */
+	so->tx.state = ISOTP_IDLE;
+	wake_up_interruptible(&so->wait);
 
-		/* we did not get any flow control frame in time */
+	return HRTIMER_NORESTART;
+}
 
-		/* report 'communication error on send' */
-		sk->sk_err = ECOMM;
-		if (!sock_flag(sk, SOCK_DEAD))
-			sk_error_report(sk);
+static enum hrtimer_restart isotp_txfr_timer_handler(struct hrtimer *hrtimer)
+{
+	struct isotp_sock *so = container_of(hrtimer, struct isotp_sock,
+					     txfrtimer);
 
-		/* reset tx state */
-		so->tx.state = ISOTP_IDLE;
-		wake_up_interruptible(&so->wait);
-		break;
+	/* start echo timeout handling and cover below protocol error */
+	hrtimer_start(&so->txtimer, ktime_set(ISOTP_ECHO_TIMEOUT, 0),
+		      HRTIMER_MODE_REL_SOFT);
 
-	default:
-		WARN_ONCE(1, "can-isotp: tx timer state %08X cfecho %08X\n",
-			  so->tx.state, so->cfecho);
-	}
+	/* cfecho should be consumed by isotp_rcv_echo() here */
+	if (so->tx.state == ISOTP_SENDING && !so->cfecho)
+		isotp_send_cframe(so);
 
-	return restart;
+	return HRTIMER_NORESTART;
 }
 
 static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
@@ -1198,6 +1188,7 @@ static int isotp_release(struct socket *sock)
 		}
 	}
 
+	hrtimer_cancel(&so->txfrtimer);
 	hrtimer_cancel(&so->txtimer);
 	hrtimer_cancel(&so->rxtimer);
 
@@ -1601,6 +1592,8 @@ static int isotp_init(struct sock *sk)
 	so->rxtimer.function = isotp_rx_timer_handler;
 	hrtimer_init(&so->txtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
 	so->txtimer.function = isotp_tx_timer_handler;
+	hrtimer_init(&so->txfrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
+	so->txfrtimer.function = isotp_txfr_timer_handler;
 
 	init_waitqueue_head(&so->wait);
 	spin_lock_init(&so->rx_lock);