From 6ef7b8a23a2022915a7e1ac1a7b847ded7d977b1 Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Wed, 22 Jan 2014 12:54:15 -0500 Subject: [PATCH] net: Correctly sync addresses from multiple sources to single device When we have multiple devices attempting to sync the same address to a single destination, each device should be permitted to sync it once. To accomplish this, pass the 'sync_cnt' of the source address when adding the addresss to the lower device. 'sync_cnt' tracks how many time a given address has been succefully synced. This way, we know that if the 'sync_cnt' passed in is 0, we should sync this address. Also, turn 'synced' member back into the counter as was originally done in commit 4543fbefe6e06a9e40d9f2b28d688393a299f079. net: count hw_addr syncs so that unsync works properly. It tracks how many time a given address has been added via a 'sync' operation. For every successfull 'sync' the counter is incremented, and for ever 'unsync', the counter is decremented. This makes sure that the address will be properly removed from the the lower device when all the upper devices have removed it. Reported-by: Andrey Dmitrov CC: Andrey Dmitrov CC: Alexandra N. Kossovsky CC: Konstantin Ushakov Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller --- net/core/dev_addr_lists.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/net/core/dev_addr_lists.c b/net/core/dev_addr_lists.c index bb504a919e33..329d5794e7dc 100644 --- a/net/core/dev_addr_lists.c +++ b/net/core/dev_addr_lists.c @@ -38,7 +38,7 @@ 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 = sync; + ha->synced = sync ? 1 : 0; ha->sync_cnt = 0; list_add_tail_rcu(&ha->list, &list->list); list->count++; @@ -48,7 +48,8 @@ static int __hw_addr_create_ex(struct netdev_hw_addr_list *list, static int __hw_addr_add_ex(struct netdev_hw_addr_list *list, const unsigned char *addr, int addr_len, - unsigned char addr_type, bool global, bool sync) + unsigned char addr_type, bool global, bool sync, + int sync_count) { struct netdev_hw_addr *ha; @@ -66,10 +67,10 @@ static int __hw_addr_add_ex(struct netdev_hw_addr_list *list, ha->global_use = true; } if (sync) { - if (ha->synced) + if (ha->synced && sync_count) return -EEXIST; else - ha->synced = true; + ha->synced++; } ha->refcount++; return 0; @@ -84,7 +85,8 @@ static int __hw_addr_add(struct netdev_hw_addr_list *list, const unsigned char *addr, int addr_len, unsigned char addr_type) { - return __hw_addr_add_ex(list, addr, addr_len, addr_type, false, false); + return __hw_addr_add_ex(list, addr, addr_len, addr_type, false, false, + 0); } static int __hw_addr_del_entry(struct netdev_hw_addr_list *list, @@ -101,7 +103,7 @@ static int __hw_addr_del_entry(struct netdev_hw_addr_list *list, ha->global_use = false; if (sync) - ha->synced = false; + ha->synced--; if (--ha->refcount) return 0; @@ -139,7 +141,7 @@ static int __hw_addr_sync_one(struct netdev_hw_addr_list *to_list, int err; err = __hw_addr_add_ex(to_list, ha->addr, addr_len, ha->type, - false, true); + false, true, ha->sync_cnt); if (err && err != -EEXIST) return err; @@ -581,7 +583,7 @@ static int __dev_mc_add(struct net_device *dev, const unsigned char *addr, netif_addr_lock_bh(dev); err = __hw_addr_add_ex(&dev->mc, addr, dev->addr_len, - NETDEV_HW_ADDR_T_MULTICAST, global, false); + NETDEV_HW_ADDR_T_MULTICAST, global, false, 0); if (!err) __dev_set_rx_mode(dev); netif_addr_unlock_bh(dev);