1 files changed, 27 insertions, 17 deletions

diff --git a/net/can/j1939/main.c b/net/can/j1939/main.c
index 8452b0fbb78c..a93af55df5fd 100644
--- a/net/can/j1939/main.c
+++ b/net/can/j1939/main.c
@@ -30,10 +30,6 @@ MODULE_ALIAS("can-proto-" __stringify(CAN_J1939));
 /* CAN_HDR: #bytes before can_frame data part */
 #define J1939_CAN_HDR (offsetof(struct can_frame, data))
 
-/* CAN_FTR: #bytes beyond data part */
-#define J1939_CAN_FTR (sizeof(struct can_frame) - J1939_CAN_HDR - \
-		 sizeof(((struct can_frame *)0)->data))
-
 /* lowest layer */
 static void j1939_can_recv(struct sk_buff *iskb, void *data)
 {
@@ -42,6 +38,10 @@ static void j1939_can_recv(struct sk_buff *iskb, void *data)
 	struct j1939_sk_buff_cb *skcb, *iskcb;
 	struct can_frame *cf;
 
+	/* make sure we only get Classical CAN frames */
+	if (!can_is_can_skb(iskb))
+		return;
+
 	/* create a copy of the skb
 	 * j1939 only delivers the real data bytes,
 	 * the header goes into sockaddr.
@@ -122,7 +122,7 @@ static void j1939_can_recv(struct sk_buff *iskb, void *data)
 #define J1939_CAN_ID CAN_EFF_FLAG
 #define J1939_CAN_MASK (CAN_EFF_FLAG | CAN_RTR_FLAG)
 
-static DEFINE_SPINLOCK(j1939_netdev_lock);
+static DEFINE_MUTEX(j1939_netdev_lock);
 
 static struct j1939_priv *j1939_priv_create(struct net_device *ndev)
 {
@@ -216,7 +216,7 @@ static void __j1939_rx_release(struct kref *kref)
 	j1939_can_rx_unregister(priv);
 	j1939_ecu_unmap_all(priv);
 	j1939_priv_set(priv->ndev, NULL);
-	spin_unlock(&j1939_netdev_lock);
+	mutex_unlock(&j1939_netdev_lock);
 }
 
 /* get pointer to priv without increasing ref counter */
@@ -244,9 +244,9 @@ static struct j1939_priv *j1939_priv_get_by_ndev(struct net_device *ndev)
 {
 	struct j1939_priv *priv;
 
-	spin_lock(&j1939_netdev_lock);
+	mutex_lock(&j1939_netdev_lock);
 	priv = j1939_priv_get_by_ndev_locked(ndev);
-	spin_unlock(&j1939_netdev_lock);
+	mutex_unlock(&j1939_netdev_lock);
 
 	return priv;
 }
@@ -256,46 +256,48 @@ struct j1939_priv *j1939_netdev_start(struct net_device *ndev)
 	struct j1939_priv *priv, *priv_new;
 	int ret;
 
-	spin_lock(&j1939_netdev_lock);
+	mutex_lock(&j1939_netdev_lock);
 	priv = j1939_priv_get_by_ndev_locked(ndev);
 	if (priv) {
 		kref_get(&priv->rx_kref);
-		spin_unlock(&j1939_netdev_lock);
+		mutex_unlock(&j1939_netdev_lock);
 		return priv;
 	}
-	spin_unlock(&j1939_netdev_lock);
+	mutex_unlock(&j1939_netdev_lock);
 
 	priv = j1939_priv_create(ndev);
 	if (!priv)
 		return ERR_PTR(-ENOMEM);
 
 	j1939_tp_init(priv);
-	spin_lock_init(&priv->j1939_socks_lock);
+	rwlock_init(&priv->j1939_socks_lock);
 	INIT_LIST_HEAD(&priv->j1939_socks);
 
-	spin_lock(&j1939_netdev_lock);
+	mutex_lock(&j1939_netdev_lock);
 	priv_new = j1939_priv_get_by_ndev_locked(ndev);
 	if (priv_new) {
 		/* Someone was faster than us, use their priv and roll
 		 * back our's.
 		 */
 		kref_get(&priv_new->rx_kref);
-		spin_unlock(&j1939_netdev_lock);
+		mutex_unlock(&j1939_netdev_lock);
 		dev_put(ndev);
 		kfree(priv);
 		return priv_new;
 	}
 	j1939_priv_set(ndev, priv);
-	spin_unlock(&j1939_netdev_lock);
 
 	ret = j1939_can_rx_register(priv);
 	if (ret < 0)
 		goto out_priv_put;
 
+	mutex_unlock(&j1939_netdev_lock);
 	return priv;
 
  out_priv_put:
 	j1939_priv_set(ndev, NULL);
+	mutex_unlock(&j1939_netdev_lock);
+
 	dev_put(ndev);
 	kfree(priv);
 
@@ -304,7 +306,7 @@ struct j1939_priv *j1939_netdev_start(struct net_device *ndev)
 
 void j1939_netdev_stop(struct j1939_priv *priv)
 {
-	kref_put_lock(&priv->rx_kref, __j1939_rx_release, &j1939_netdev_lock);
+	kref_put_mutex(&priv->rx_kref, __j1939_rx_release, &j1939_netdev_lock);
 	j1939_priv_put(priv);
 }
 
@@ -332,8 +334,11 @@ int j1939_send_one(struct j1939_priv *priv, struct sk_buff *skb)
 	/* re-claim the CAN_HDR from the SKB */
 	cf = skb_push(skb, J1939_CAN_HDR);
 
+	/* initialize header structure */
+	memset(cf, 0, J1939_CAN_HDR);
+
 	/* make it a full can frame again */
-	skb_put(skb, J1939_CAN_FTR + (8 - dlc));
+	skb_put_zero(skb, 8 - dlc);
 
 	canid = CAN_EFF_FLAG |
 		(skcb->priority << 26) |
@@ -372,6 +377,11 @@ static int j1939_netdev_notify(struct notifier_block *nb,
 		j1939_sk_netdev_event_netdown(priv);
 		j1939_ecu_unmap_all(priv);
 		break;
+	case NETDEV_UNREGISTER:
+		j1939_cancel_active_session(priv, NULL);
+		j1939_sk_netdev_event_netdown(priv);
+		j1939_sk_netdev_event_unregister(priv);
+		break;
 	}
 
 	j1939_priv_put(priv);