net: fix network driver ndo_start_xmit() return values (part 1)

Fix up drivers that return an errno value to qdisc_restart(), causing
qdisc_restart() to print a warning and requeue/retransmit the skb.

- xpnet: memory allocation error, intention is to drop
- ethoc: oversized packet, packet must be dropped
- ibmlana: skb freed: use after free
- rrunner: skb freed: use after free

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 6 insertions, 7 deletions

diff --git a/drivers/net/ethoc.c b/drivers/net/ethoc.c
index 91a9b1a33764..ceb6a9c357ad 100644
--- a/drivers/net/ethoc.c
+++ b/drivers/net/ethoc.c
@@ -811,7 +811,7 @@ static int ethoc_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
         if (unlikely(skb->len > ETHOC_BUFSIZ)) {
                 priv->stats.tx_errors++;
-                return -EMSGSIZE;
+                goto out;
         }
 
         entry = priv->cur_tx % priv->num_tx;
@@ -840,9 +840,9 @@ static int ethoc_start_xmit(struct sk_buff *skb, struct net_device *dev)
         }
 
         dev->trans_start = jiffies;
-        dev_kfree_skb(skb);
-
         spin_unlock_irq(&priv->lock);
+out:
+        dev_kfree_skb(skb);
         return NETDEV_TX_OK;
 }
 
diff --git a/drivers/net/ibmlana.c b/drivers/net/ibmlana.c
index c25bc0bc0b25..448098d3b39b 100644
--- a/drivers/net/ibmlana.c
+++ b/drivers/net/ibmlana.c
@@ -815,7 +815,7 @@ static int ibmlana_close(struct net_device *dev)
 static int ibmlana_tx(struct sk_buff *skb, struct net_device *dev)
 {
         ibmlana_priv *priv = netdev_priv(dev);
-        int retval = 0, tmplen, addr;
+        int tmplen, addr;
         unsigned long flags;
         tda_t tda;
         int baddr;
@@ -824,7 +824,6 @@ static int ibmlana_tx(struct sk_buff *skb, struct net_device *dev)
            the upper layer is in deep desperation and we simply ignore the frame. */
 
         if (priv->txusedcnt >= TXBUFCNT) {
-                retval = -EIO;
                 dev->stats.tx_dropped++;
                 goto tx_done;
         }
@@ -874,7 +873,7 @@ static int ibmlana_tx(struct sk_buff *skb, struct net_device *dev)
         spin_unlock_irqrestore(&priv->lock, flags);
 tx_done:
         dev_kfree_skb(skb);
-        return retval;
+        return NETDEV_TX_OK;
 }
 
 /* switch receiver mode. */
diff --git a/drivers/net/rrunner.c b/drivers/net/rrunner.c
index d890829a9acc..81dbcbb910f4 100644
--- a/drivers/net/rrunner.c
+++ b/drivers/net/rrunner.c
@@ -1425,7 +1425,7 @@ static int rr_start_xmit(struct sk_buff *skb, struct net_device *dev)
                 if (!(new_skb = dev_alloc_skb(len + 8))) {
                         dev_kfree_skb(skb);
                         netif_wake_queue(dev);
-                        return -EBUSY;
+                        return NETDEV_TX_OK;
                 }
                 skb_reserve(new_skb, 8);
                 skb_put(new_skb, len);