net: count hw_addr syncs so that unsync works properly.

A few drivers use dev_uc_sync/unsync to synchronize the
address lists from master down to slave/lower devices.  In
some cases (bond/team) a single address list is synched down
to multiple devices.  At the time of unsync, we have a leak
in these lower devices, because "synced" is treated as a
boolean and the address will not be unsynced for anything after
the first device/call.

Treat "synced" as a count (same as refcount) and allow all
unsync calls to work.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 4 insertions, 4 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 8bfa95600e48..6151e903eef0 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -210,9 +210,9 @@ struct netdev_hw_addr {
 #define NETDEV_HW_ADDR_T_SLAVE          3
 #define NETDEV_HW_ADDR_T_UNICAST        4
 #define NETDEV_HW_ADDR_T_MULTICAST      5
-        bool                    synced;
         bool                    global_use;
         int                     refcount;
+        int                     synced;
         struct rcu_head         rcu_head;
 };
 
diff --git a/net/core/dev_addr_lists.c b/net/core/dev_addr_lists.c
index bd2eb9d3e369..abdc9e6ef33e 100644
--- a/net/core/dev_addr_lists.c
+++ b/net/core/dev_addr_lists.c
@@ -37,7 +37,7 @@ static int __hw_addr_create_ex(struct netdev_hw_addr_list *list,
         ha->type = addr_type;
         ha->refcount = 1;
         ha->global_use = global;
-        ha->synced = false;
+        ha->synced = 0;
         list_add_tail_rcu(&ha->list, &list->list);
         list->count++;
 
@@ -165,7 +165,7 @@ int __hw_addr_sync(struct netdev_hw_addr_list *to_list,
                                             addr_len, ha->type);
                         if (err)
                                 break;
-                        ha->synced = true;
+                        ha->synced++;
                         ha->refcount++;
                 } else if (ha->refcount == 1) {
                         __hw_addr_del(to_list, ha->addr, addr_len, ha->type);
@@ -186,7 +186,7 @@ void __hw_addr_unsync(struct netdev_hw_addr_list *to_list,
                 if (ha->synced) {
                         __hw_addr_del(to_list, ha->addr,
                                       addr_len, ha->type);
-                        ha->synced = false;
+                        ha->synced--;
                         __hw_addr_del(from_list, ha->addr,
                                       addr_len, ha->type);
                 }