diff options
Diffstat (limited to 'net/core/rtnetlink.c')
| -rw-r--r-- | net/core/rtnetlink.c | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index bc290413a49d..45936922d7e2 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -75,6 +75,12 @@ void rtnl_lock(void) } EXPORT_SYMBOL(rtnl_lock); +int rtnl_lock_killable(void) +{ + return mutex_lock_killable(&rtnl_mutex); +} +EXPORT_SYMBOL(rtnl_lock_killable); + static struct sk_buff *defer_kfree_skb_list; void rtnl_kfree_skbs(struct sk_buff *head, struct sk_buff *tail) { @@ -406,7 +412,9 @@ static void __rtnl_kill_links(struct net *net, struct rtnl_link_ops *ops) * __rtnl_link_unregister - Unregister rtnl_link_ops from rtnetlink. * @ops: struct rtnl_link_ops * to unregister * - * The caller must hold the rtnl_mutex. + * The caller must hold the rtnl_mutex and guarantee net_namespace_list + * integrity (hold pernet_ops_rwsem for writing to close the race + * with setup_net() and cleanup_net()). */ void __rtnl_link_unregister(struct rtnl_link_ops *ops) { @@ -432,6 +440,9 @@ static void rtnl_lock_unregistering_all(void) for (;;) { unregistering = false; rtnl_lock(); + /* We held write locked pernet_ops_rwsem, and parallel + * setup_net() and cleanup_net() are not possible. + */ for_each_net(net) { if (net->dev_unreg_count > 0) { unregistering = true; @@ -453,12 +464,12 @@ static void rtnl_lock_unregistering_all(void) */ void rtnl_link_unregister(struct rtnl_link_ops *ops) { - /* Close the race with cleanup_net() */ - mutex_lock(&net_mutex); + /* Close the race with setup_net() and cleanup_net() */ + down_write(&pernet_ops_rwsem); rtnl_lock_unregistering_all(); __rtnl_link_unregister(ops); rtnl_unlock(); - mutex_unlock(&net_mutex); + up_write(&pernet_ops_rwsem); } EXPORT_SYMBOL_GPL(rtnl_link_unregister); |