1 files changed, 13 insertions, 14 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 8092f01713fb..8eb50e2292fb 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1880,6 +1880,17 @@ static int dev_gso_segment(struct sk_buff *skb)
         return 0;
 }
 
+/*
+ * Try to orphan skb early, right before transmission by the device.
+ * We cannot orphan skb if tx timestamp is requested, since
+ * drivers need to call skb_tstamp_tx() to send the timestamp.
+ */
+static inline void skb_orphan_try(struct sk_buff *skb)
+{
+        if (!skb_tx(skb)->flags)
+                skb_orphan(skb);
+}
+
 int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
                         struct netdev_queue *txq)
 {
@@ -1904,23 +1915,10 @@ int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
                 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
                         skb_dst_drop(skb);
 
+                skb_orphan_try(skb);
                 rc = ops->ndo_start_xmit(skb, dev);
                 if (rc == NETDEV_TX_OK)
                         txq_trans_update(txq);
-                /*
-                 * TODO: if skb_orphan() was called by
-                 * dev->hard_start_xmit() (for example, the unmodified
-                 * igb driver does that; bnx2 doesn't), then
-                 * skb_tx_software_timestamp() will be unable to send
-                 * back the time stamp.
-                 *
-                 * How can this be prevented? Always create another
-                 * reference to the socket before calling
-                 * dev->hard_start_xmit()? Prevent that skb_orphan()
-                 * does anything in dev->hard_start_xmit() by clearing
-                 * the skb destructor before the call and restoring it
-                 * afterwards, then doing the skb_orphan() ourselves?
-                 */
                 return rc;
         }
 
@@ -1938,6 +1936,7 @@ gso:
                 if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
                         skb_dst_drop(nskb);
 
+                skb_orphan_try(nskb);
                 rc = ops->ndo_start_xmit(nskb, dev);
                 if (unlikely(rc != NETDEV_TX_OK)) {
                         if (rc & ~NETDEV_TX_MASK)