From b0ab2fabb5b91da99c189db02e91ae10bc8355c5 Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Thu, 26 Jun 2014 09:58:25 +0200 Subject: [PATCH] rtnetlink: allow to register ops without ops->setup set So far, it is assumed that ops->setup is filled up. But there might be case that ops might make sense even without ->setup. In that case, forbid to newlink and dellink. This allows to register simple rtnl link ops containing only ->kind. That allows consistent way of passing device kind (either device-kind or slave-kind) to userspace. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- net/core/dev.c | 2 +- net/core/rtnetlink.c | 12 ++++++++++-- 2 files changed, 11 insertions(+), 3 deletions(-) diff --git a/net/core/dev.c b/net/core/dev.c index de9774119541..6e2a2cd82321 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -7091,7 +7091,7 @@ static void __net_exit default_device_exit_batch(struct list_head *net_list) rtnl_lock_unregistering(net_list); list_for_each_entry(net, net_list, exit_list) { for_each_netdev_reverse(net, dev) { - if (dev->rtnl_link_ops) + if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink) dev->rtnl_link_ops->dellink(dev, &dev_kill_list); else unregister_netdevice_queue(dev, &dev_kill_list); diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 1063996f8317..27acaf7ff6d7 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -299,7 +299,12 @@ int __rtnl_link_register(struct rtnl_link_ops *ops) if (rtnl_link_ops_get(ops->kind)) return -EEXIST; - if (!ops->dellink) + /* The check for setup is here because if ops + * does not have that filled up, it is not possible + * to use the ops for creating device. So do not + * fill up dellink as well. That disables rtnl_dellink. + */ + if (ops->setup && !ops->dellink) ops->dellink = unregister_netdevice_queue; list_add_tail(&ops->list, &link_ops); @@ -1777,7 +1782,7 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh) return -ENODEV; ops = dev->rtnl_link_ops; - if (!ops) + if (!ops || !ops->dellink) return -EOPNOTSUPP; ops->dellink(dev, &list_kill); @@ -2038,6 +2043,9 @@ replay: return -EOPNOTSUPP; } + if (!ops->setup) + return -EOPNOTSUPP; + if (!ifname[0]) snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind); -- 2.39.5