Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw

[~andy/linux] / net / core / neighbour.c

diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index d81d026138f0810471ce4cf2540c0ec4229d853f..117afaf512689b4de570ddb0c32869a4c5532918 100644 (file)
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -474,8 +474,8 @@ struct neighbour *neigh_lookup_nodev(struct neigh_table *tbl, struct net *net,
 }
 EXPORT_SYMBOL(neigh_lookup_nodev);
 
-struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
-                              struct net_device *dev)
+struct neighbour *__neigh_create(struct neigh_table *tbl, const void *pkey,
+                                struct net_device *dev, bool want_ref)
 {
        u32 hash_val;
        int key_len = tbl->key_len;
@@ -535,14 +535,16 @@ struct neighbour *neigh_create(struct neigh_table *tbl, const void *pkey,
             n1 = rcu_dereference_protected(n1->next,
                        lockdep_is_held(&tbl->lock))) {
                if (dev == n1->dev && !memcmp(n1->primary_key, pkey, key_len)) {
-                       neigh_hold(n1);
+                       if (want_ref)
+                               neigh_hold(n1);
                        rc = n1;
                        goto out_tbl_unlock;
                }
        }
 
        n->dead = 0;
-       neigh_hold(n);
+       if (want_ref)
+               neigh_hold(n);
        rcu_assign_pointer(n->next,
                           rcu_dereference_protected(nht->hash_buckets[hash_val],
                                                     lockdep_is_held(&tbl->lock)));
@@ -558,7 +560,7 @@ out_neigh_release:
        neigh_release(n);
        goto out;
 }
-EXPORT_SYMBOL(neigh_create);
+EXPORT_SYMBOL(__neigh_create);
 
 static u32 pneigh_hash(const void *pkey, int key_len)
 {
@@ -1199,10 +1201,23 @@ int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
                        write_unlock_bh(&neigh->lock);
 
                        rcu_read_lock();
-                       /* On shaper/eql skb->dst->neighbour != neigh :( */
-                       if (dst && (n2 = dst_get_neighbour_noref(dst)) != NULL)
-                               n1 = n2;
+
+                       /* Why not just use 'neigh' as-is?  The problem is that
+                        * things such as shaper, eql, and sch_teql can end up
+                        * using alternative, different, neigh objects to output
+                        * the packet in the output path.  So what we need to do
+                        * here is re-lookup the top-level neigh in the path so
+                        * we can reinject the packet there.
+                        */
+                       n2 = NULL;
+                       if (dst) {
+                               n2 = dst_neigh_lookup_skb(dst, skb);
+                               if (n2)
+                                       n1 = n2;
+                       }
                        n1->output(n1, skb);
+                       if (n2)
+                               neigh_release(n2);
                        rcu_read_unlock();
 
                        write_lock_bh(&neigh->lock);