Merge tag 'linux-can-fixes-for-6.2-20230202' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
can 2023-02-02

The first patch is by Ziyang Xuan and removes a errant WARN_ON_ONCE()
in the CAN J1939 protocol.

The next 3 patches are by Oliver Hartkopp. The first 2 target the CAN
ISO-TP protocol and fix the state machine with respect to signals and
a regression found by the syzbot.

The last patch is by me an missing assignment during the ethtool ring
configuration callback.

* tag 'linux-can-fixes-for-6.2-20230202' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can:
  can: mcp251xfd: mcp251xfd_ring_set_ringparam(): assign missing tx_obj_num_coalesce_irq
  can: isotp: split tx timer into transmission and timeout
  can: isotp: handle wait_event_interruptible() return values
  can: raw: fix CAN FD frame transmissions over CAN XL devices
  can: j1939: fix errant WARN_ON_ONCE in j1939_session_deactivate
====================

Link: https://lore.kernel.org/r/20230202094135.2293939-1-mkl@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

4 files changed, 65 insertions, 56 deletions

diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ethtool.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ethtool.c
index 3585f02575dfbd..57eeb066a9456b 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ethtool.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ethtool.c
@@ -48,6 +48,7 @@ mcp251xfd_ring_set_ringparam(struct net_device *ndev,
 	priv->rx_obj_num = layout.cur_rx;
 	priv->rx_obj_num_coalesce_irq = layout.rx_coalesce;
 	priv->tx->obj_num = layout.cur_tx;
+	priv->tx_obj_num_coalesce_irq = layout.tx_coalesce;
 
 	return 0;
 }
diff --git a/net/can/isotp.c b/net/can/isotp.c
index 608f8c24ae46b6..fc81d77724a131 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:
-
-		/* 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;
+	/* don't handle timeouts in IDLE state */
+	if (so->tx.state == ISOTP_IDLE)
+		return HRTIMER_NORESTART;
 
-			/* push out the next consecutive frame */
-			isotp_send_cframe(so);
-			break;
-		}
+	/* we did not get any flow control or echo frame in time */
 
-		/* 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)
@@ -1162,6 +1152,10 @@ static int isotp_release(struct socket *sock)
 	/* wait for complete transmission of current pdu */
 	wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
 
+	/* force state machines to be idle also when a signal occurred */
+	so->tx.state = ISOTP_IDLE;
+	so->rx.state = ISOTP_IDLE;
+
 	spin_lock(&isotp_notifier_lock);
 	while (isotp_busy_notifier == so) {
 		spin_unlock(&isotp_notifier_lock);
@@ -1194,6 +1188,7 @@ static int isotp_release(struct socket *sock)
 		}
 	}
 
+	hrtimer_cancel(&so->txfrtimer);
 	hrtimer_cancel(&so->txtimer);
 	hrtimer_cancel(&so->rxtimer);
 
@@ -1597,6 +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);
diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index 5c722b55fe237f..fce9b9ebf13f66 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -1092,10 +1092,6 @@ static bool j1939_session_deactivate(struct j1939_session *session)
 	bool active;
 
 	j1939_session_list_lock(priv);
-	/* This function should be called with a session ref-count of at
-	 * least 2.
-	 */
-	WARN_ON_ONCE(kref_read(&session->kref) < 2);
 	active = j1939_session_deactivate_locked(session);
 	j1939_session_list_unlock(priv);
 
diff --git a/net/can/raw.c b/net/can/raw.c
index 81071cdb030101..ba86782ba8bb3c 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -132,8 +132,8 @@ static void raw_rcv(struct sk_buff *oskb, void *data)
 		return;
 
 	/* make sure to not pass oversized frames to the socket */
-	if ((can_is_canfd_skb(oskb) && !ro->fd_frames && !ro->xl_frames) ||
-	    (can_is_canxl_skb(oskb) && !ro->xl_frames))
+	if ((!ro->fd_frames && can_is_canfd_skb(oskb)) ||
+	    (!ro->xl_frames && can_is_canxl_skb(oskb)))
 		return;
 
 	/* eliminate multiple filter matches for the same skb */
@@ -670,6 +670,11 @@ static int raw_setsockopt(struct socket *sock, int level, int optname,
 		if (copy_from_sockptr(&ro->fd_frames, optval, optlen))
 			return -EFAULT;
 
+		/* Enabling CAN XL includes CAN FD */
+		if (ro->xl_frames && !ro->fd_frames) {
+			ro->fd_frames = ro->xl_frames;
+			return -EINVAL;
+		}
 		break;
 
 	case CAN_RAW_XL_FRAMES:
@@ -679,6 +684,9 @@ static int raw_setsockopt(struct socket *sock, int level, int optname,
 		if (copy_from_sockptr(&ro->xl_frames, optval, optlen))
 			return -EFAULT;
 
+		/* Enabling CAN XL includes CAN FD */
+		if (ro->xl_frames)
+			ro->fd_frames = ro->xl_frames;
 		break;
 
 	case CAN_RAW_JOIN_FILTERS:
@@ -786,6 +794,25 @@ static int raw_getsockopt(struct socket *sock, int level, int optname,
 	return 0;
 }
 
+static bool raw_bad_txframe(struct raw_sock *ro, struct sk_buff *skb, int mtu)
+{
+	/* Classical CAN -> no checks for flags and device capabilities */
+	if (can_is_can_skb(skb))
+		return false;
+
+	/* CAN FD -> needs to be enabled and a CAN FD or CAN XL device */
+	if (ro->fd_frames && can_is_canfd_skb(skb) &&
+	    (mtu == CANFD_MTU || can_is_canxl_dev_mtu(mtu)))
+		return false;
+
+	/* CAN XL -> needs to be enabled and a CAN XL device */
+	if (ro->xl_frames && can_is_canxl_skb(skb) &&
+	    can_is_canxl_dev_mtu(mtu))
+		return false;
+
+	return true;
+}
+
 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 {
 	struct sock *sk = sock->sk;
@@ -833,20 +860,8 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 		goto free_skb;
 
 	err = -EINVAL;
-	if (ro->xl_frames && can_is_canxl_dev_mtu(dev->mtu)) {
-		/* CAN XL, CAN FD and Classical CAN */
-		if (!can_is_canxl_skb(skb) && !can_is_canfd_skb(skb) &&
-		    !can_is_can_skb(skb))
-			goto free_skb;
-	} else if (ro->fd_frames && dev->mtu == CANFD_MTU) {
-		/* CAN FD and Classical CAN */
-		if (!can_is_canfd_skb(skb) && !can_is_can_skb(skb))
-			goto free_skb;
-	} else {
-		/* Classical CAN */
-		if (!can_is_can_skb(skb))
-			goto free_skb;
-	}
+	if (raw_bad_txframe(ro, skb, dev->mtu))
+		goto free_skb;
 
 	sockcm_init(&sockc, sk);
 	if (msg->msg_controllen) {