Copy skbs when we save them.

diff --git a/datapath/forward.c b/datapath/forward.c
index ed092fe..33b3a5e 100644 (file)
--- a/datapath/forward.c
+++ b/datapath/forward.c
@@ -465,6 +465,11 @@ uint32_t fwd_save_skb(struct sk_buff *skb)
        unsigned long int flags;
        uint32_t id;
 
+       /* FIXME: Probably just need a skb_clone() here. */
+       skb = skb_copy(skb, GFP_ATOMIC);
+       if (!skb)
+               return -1;
+
        spin_lock_irqsave(&buffer_lock, flags);
        buffer_idx = (buffer_idx + 1) & PKT_BUFFER_MASK;
        p = &buffers[buffer_idx];
@@ -473,9 +478,13 @@ uint32_t fwd_save_skb(struct sk_buff *skb)
                 * OVERWRITE_SECS old. */
                if (time_before(jiffies, p->exp_jiffies)) {
                        spin_unlock_irqrestore(&buffer_lock, flags);
+                       kfree_skb(skb);
                        return -1;
                } else {
-                       /* Defer kfree_skb() until interrupts re-enabled. */
+                       /* Defer kfree_skb() until interrupts re-enabled.
+                        * FIXME: we only need to do that if it has a
+                        * destructor, but it never should since we orphan
+                        * sk_buffs on entry. */
                        old_skb = p->skb;
                }
        }
@@ -483,7 +492,6 @@ uint32_t fwd_save_skb(struct sk_buff *skb)
         * special. */
        if (++p->cookie >= (1u << PKT_COOKIE_BITS) - 1)
                p->cookie = 0;
-       skb_get(skb);
        p->skb = skb;
        p->exp_jiffies = jiffies + OVERWRITE_JIFFIES;
        id = buffer_idx | (p->cookie << PKT_BUFFER_BITS);