1 files changed, 26 insertions, 6 deletions

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index f0b9a1e1db46..39b99f57c265 100644
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -245,7 +245,7 @@ static void can_flush_echo_skb(struct net_device *dev)
         struct net_device_stats *stats = &dev->stats;
         int i;
 
-        for (i = 0; i < CAN_ECHO_SKB_MAX; i++) {
+        for (i = 0; i < priv->echo_skb_max; i++) {
                 if (priv->echo_skb[i]) {
                         kfree_skb(priv->echo_skb[i]);
                         priv->echo_skb[i] = NULL;
@@ -262,10 +262,13 @@ static void can_flush_echo_skb(struct net_device *dev)
  * of the device driver. The driver must protect access to
  * priv->echo_skb, if necessary.
  */
-void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, int idx)
+void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
+                      unsigned int idx)
 {
         struct can_priv *priv = netdev_priv(dev);
 
+        BUG_ON(idx >= priv->echo_skb_max);
+
         /* check flag whether this packet has to be looped back */
         if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK) {
                 kfree_skb(skb);
@@ -311,10 +314,12 @@ EXPORT_SYMBOL_GPL(can_put_echo_skb);
  * is handled in the device driver. The driver must protect
  * access to priv->echo_skb, if necessary.
  */
-void can_get_echo_skb(struct net_device *dev, int idx)
+void can_get_echo_skb(struct net_device *dev, unsigned int idx)
 {
         struct can_priv *priv = netdev_priv(dev);
 
+        BUG_ON(idx >= priv->echo_skb_max);
+
         if (priv->echo_skb[idx]) {
                 netif_rx(priv->echo_skb[idx]);
                 priv->echo_skb[idx] = NULL;
@@ -327,10 +332,12 @@ EXPORT_SYMBOL_GPL(can_get_echo_skb);
   *
   * The function is typically called when TX failed.
   */
-void can_free_echo_skb(struct net_device *dev, int idx)
+void can_free_echo_skb(struct net_device *dev, unsigned int idx)
 {
         struct can_priv *priv = netdev_priv(dev);
 
+        BUG_ON(idx >= priv->echo_skb_max);
+
         if (priv->echo_skb[idx]) {
                 kfree_skb(priv->echo_skb[idx]);
                 priv->echo_skb[idx] = NULL;
@@ -445,17 +452,30 @@ static void can_setup(struct net_device *dev)
 /*
  * Allocate and setup space for the CAN network device
  */
-struct net_device *alloc_candev(int sizeof_priv)
+struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max)
 {
         struct net_device *dev;
         struct can_priv *priv;
+        int size;
 
-        dev = alloc_netdev(sizeof_priv, "can%d", can_setup);
+        if (echo_skb_max)
+                size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) +
+                        echo_skb_max * sizeof(struct sk_buff *);
+        else
+                size = sizeof_priv;
+
+        dev = alloc_netdev(size, "can%d", can_setup);
         if (!dev)
                 return NULL;
 
         priv = netdev_priv(dev);
 
+        if (echo_skb_max) {
+                priv->echo_skb_max = echo_skb_max;
+                priv->echo_skb = (void *)priv +
+                        ALIGN(sizeof_priv, sizeof(struct sk_buff *));
+        }
+
         priv->state = CAN_STATE_STOPPED;
 
         init_timer(&priv->restart_timer);