can: kvaser_usb: Various fixes

index 07f687f29b34..8e11cda85624 100644
@@ -310,6 +310,38 @@ struct kvaser_cmd {
 	} u;
 } __packed;
 
+#define CMD_SIZE_ANY 0xff
+#define kvaser_fsize(field) sizeof_field(struct kvaser_cmd, field)
+
+static const u8 kvaser_usb_leaf_cmd_sizes_leaf[] = {
+	[CMD_START_CHIP_REPLY]		= kvaser_fsize(u.simple),
+	[CMD_STOP_CHIP_REPLY]		= kvaser_fsize(u.simple),
+	[CMD_GET_CARD_INFO_REPLY]	= kvaser_fsize(u.cardinfo),
+	[CMD_TX_ACKNOWLEDGE]		= kvaser_fsize(u.tx_acknowledge_header),
+	[CMD_GET_SOFTWARE_INFO_REPLY]	= kvaser_fsize(u.leaf.softinfo),
+	[CMD_RX_STD_MESSAGE]		= kvaser_fsize(u.leaf.rx_can),
+	[CMD_RX_EXT_MESSAGE]		= kvaser_fsize(u.leaf.rx_can),
+	[CMD_LEAF_LOG_MESSAGE]		= kvaser_fsize(u.leaf.log_message),
+	[CMD_CHIP_STATE_EVENT]		= kvaser_fsize(u.leaf.chip_state_event),
+	[CMD_CAN_ERROR_EVENT]		= kvaser_fsize(u.leaf.error_event),
+	/* ignored events: */
+	[CMD_FLUSH_QUEUE_REPLY]		= CMD_SIZE_ANY,
+};
+
+static const u8 kvaser_usb_leaf_cmd_sizes_usbcan[] = {
+	[CMD_START_CHIP_REPLY]		= kvaser_fsize(u.simple),
+	[CMD_STOP_CHIP_REPLY]		= kvaser_fsize(u.simple),
+	[CMD_GET_CARD_INFO_REPLY]	= kvaser_fsize(u.cardinfo),
+	[CMD_TX_ACKNOWLEDGE]		= kvaser_fsize(u.tx_acknowledge_header),
+	[CMD_GET_SOFTWARE_INFO_REPLY]	= kvaser_fsize(u.usbcan.softinfo),
+	[CMD_RX_STD_MESSAGE]		= kvaser_fsize(u.usbcan.rx_can),
+	[CMD_RX_EXT_MESSAGE]		= kvaser_fsize(u.usbcan.rx_can),
+	[CMD_CHIP_STATE_EVENT]		= kvaser_fsize(u.usbcan.chip_state_event),
+	[CMD_CAN_ERROR_EVENT]		= kvaser_fsize(u.usbcan.error_event),
+	/* ignored events: */
+	[CMD_USBCAN_CLOCK_OVERFLOW_EVENT] = CMD_SIZE_ANY,
+};
+
 /* Summary of a kvaser error event, for a unified Leaf/Usbcan error
  * handling. Some discrepancies between the two families exist:
  *

@@ -397,6 +429,43 @@ static const struct kvaser_usb_dev_cfg kvaser_usb_leaf_imx_dev_cfg_32mhz = {
 	.bittiming_const = &kvaser_usb_flexc_bittiming_const,
 };
 
+static int kvaser_usb_leaf_verify_size(const struct kvaser_usb *dev,
+				       const struct kvaser_cmd *cmd)
+{
+	/* buffer size >= cmd->len ensured by caller */
+	u8 min_size = 0;
+
+	switch (dev->driver_info->family) {
+	case KVASER_LEAF:
+		if (cmd->id < ARRAY_SIZE(kvaser_usb_leaf_cmd_sizes_leaf))
+			min_size = kvaser_usb_leaf_cmd_sizes_leaf[cmd->id];
+		break;
+	case KVASER_USBCAN:
+		if (cmd->id < ARRAY_SIZE(kvaser_usb_leaf_cmd_sizes_usbcan))
+			min_size = kvaser_usb_leaf_cmd_sizes_usbcan[cmd->id];
+		break;
+	}
+
+	if (min_size == CMD_SIZE_ANY)
+		return 0;
+
+	if (min_size) {
+		min_size += CMD_HEADER_LEN;
+		if (cmd->len >= min_size)
+			return 0;
+
+		dev_err_ratelimited(&dev->intf->dev,
+				    "Received command %u too short (size %u, needed %u)",
+				    cmd->id, cmd->len, min_size);
+		return -EIO;
+	}
+
+	dev_warn_ratelimited(&dev->intf->dev,
+			     "Unhandled command (%d, size %d)\n",
+			     cmd->id, cmd->len);
+	return -EINVAL;
+}
+
 static void *
 kvaser_usb_leaf_frame_to_cmd(const struct kvaser_usb_net_priv *priv,
 			     const struct sk_buff *skb, int *cmd_len,

@@ -502,6 +571,9 @@ static int kvaser_usb_leaf_wait_cmd(const struct kvaser_usb *dev, u8 id,
 end:
 	kfree(buf);
 
+	if (err == 0)
+		err = kvaser_usb_leaf_verify_size(dev, cmd);
+
 	return err;
 }
 

@@ -1133,6 +1205,9 @@ static void kvaser_usb_leaf_stop_chip_reply(const struct kvaser_usb *dev,
 static void kvaser_usb_leaf_handle_command(const struct kvaser_usb *dev,
 					   const struct kvaser_cmd *cmd)
 {
+	if (kvaser_usb_leaf_verify_size(dev, cmd) < 0)
+		return;
+
 	switch (cmd->id) {
 	case CMD_START_CHIP_REPLY:
 		kvaser_usb_leaf_start_chip_reply(dev, cmd);

index 824cab80aa02..c2bce6773adc 100644
@@ -729,6 +729,7 @@ static int kvaser_usb_init_one(struct kvaser_usb *dev, int channel)
 	init_usb_anchor(&priv->tx_submitted);
 	init_completion(&priv->start_comp);
 	init_completion(&priv->stop_comp);
+	init_completion(&priv->flush_comp);
 	priv->can.ctrlmode_supported = 0;
 
 	priv->dev = dev;

index 6871d474dabf..7b52fda73d82 100644
@@ -1916,7 +1916,7 @@ static int kvaser_usb_hydra_flush_queue(struct kvaser_usb_net_priv *priv)
 {
 	int err;
 
-	init_completion(&priv->flush_comp);
+	reinit_completion(&priv->flush_comp);
 
 	err = kvaser_usb_hydra_send_simple_cmd(priv->dev, CMD_FLUSH_QUEUE,
 					       priv->channel);

index 841da29cef93..f6c0938027ec 100644
@@ -178,6 +178,8 @@ struct kvaser_usb_dev_cfg {
 extern const struct kvaser_usb_dev_ops kvaser_usb_hydra_dev_ops;
 extern const struct kvaser_usb_dev_ops kvaser_usb_leaf_dev_ops;
 
+void kvaser_usb_unlink_tx_urbs(struct kvaser_usb_net_priv *priv);
+
 int kvaser_usb_recv_cmd(const struct kvaser_usb *dev, void *cmd, int len,
 			int *actual_len);
 

index c2bce6773adc..e91648ed7386 100644
@@ -477,7 +477,7 @@ static void kvaser_usb_reset_tx_urb_contexts(struct kvaser_usb_net_priv *priv)
 /* This method might sleep. Do not call it in the atomic context
  * of URB completions.
  */
-static void kvaser_usb_unlink_tx_urbs(struct kvaser_usb_net_priv *priv)
+void kvaser_usb_unlink_tx_urbs(struct kvaser_usb_net_priv *priv)
 {
 	usb_kill_anchored_urbs(&priv->tx_submitted);
 	kvaser_usb_reset_tx_urb_contexts(priv);

index 8e11cda85624..59c220ef3049 100644
@@ -1426,6 +1426,8 @@ static int kvaser_usb_leaf_set_mode(struct net_device *netdev,
 
 	switch (mode) {
 	case CAN_MODE_START:
+		kvaser_usb_unlink_tx_urbs(priv);
+
 		err = kvaser_usb_leaf_simple_cmd_async(priv, CMD_START_CHIP);
 		if (err)
 			return err;

index 59c220ef3049..50f2ac8319ff 100644
@@ -1431,6 +1431,8 @@ static int kvaser_usb_leaf_set_mode(struct net_device *netdev,
 		err = kvaser_usb_leaf_simple_cmd_async(priv, CMD_START_CHIP);
 		if (err)
 			return err;
+
+		priv->can.state = CAN_STATE_ERROR_ACTIVE;
 		break;
 	default:
 		return -EOPNOTSUPP;