[PATCH net-next 5/6] net: require instance lock for NETDEV_DOWN/GOING_DOWN notifiers

[Stanislav Fomichev <sdf.kernel@gmail.com>]

Sprinkle a few asserts about ops lock: netif_close_many and __dev_notify_flags
should now consistently run under the lock

Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
---
 Documentation/networking/netdevices.rst | 2 ++
 net/core/dev.c                          | 3 +++
 net/core/lock_debug.c                   | 4 ++--
 3 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/Documentation/networking/netdevices.rst b/Documentation/networking/netdevices.rst
index d2a238f8cc8b..1bb68a73bb67 100644
--- a/Documentation/networking/netdevices.rst
+++ b/Documentation/networking/netdevices.rst
@@ -421,6 +421,8 @@ For devices with locked ops, currently only the following notifiers are
 * ``NETDEV_CHANGENAME``
 * ``NETDEV_REGISTER``
 * ``NETDEV_UP``
+* ``NETDEV_DOWN``
+* ``NETDEV_GOING_DOWN``
 
 The following notifiers are running without the lock:
 * ``NETDEV_UNREGISTER``
diff --git a/net/core/dev.c b/net/core/dev.c
index 9d49493f4fb5..714d05283500 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1802,6 +1802,7 @@ void netif_close_many(struct list_head *head, bool unlink)
 	__dev_close_many(head);
 
 	list_for_each_entry_safe(dev, tmp, head, close_list) {
+		netdev_assert_locked_ops_compat(dev);
 		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL);
 		call_netdevice_notifiers(NETDEV_DOWN, dev);
 		if (unlink)
@@ -9787,6 +9788,8 @@ void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
 {
 	unsigned int changes = dev->flags ^ old_flags;
 
+	netdev_assert_locked_ops_compat(dev);
+
 	if (gchanges)
 		rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC, portid, nlh);
 
diff --git a/net/core/lock_debug.c b/net/core/lock_debug.c
index 8a81c5430705..abc4c00728b1 100644
--- a/net/core/lock_debug.c
+++ b/net/core/lock_debug.c
@@ -24,15 +24,15 @@ int netdev_debug_event(struct notifier_block *nb, unsigned long event,
 	case NETDEV_CHANGE:
 	case NETDEV_REGISTER:
 	case NETDEV_UP:
+	case NETDEV_DOWN:
+	case NETDEV_GOING_DOWN:
 		netdev_assert_locked_ops_compat(dev);
 		fallthrough;
-	case NETDEV_DOWN:
 	case NETDEV_REBOOT:
 	case NETDEV_UNREGISTER:
 	case NETDEV_CHANGEMTU:
 	case NETDEV_CHANGEADDR:
 	case NETDEV_PRE_CHANGEADDR:
-	case NETDEV_GOING_DOWN:
 	case NETDEV_FEAT_CHANGE:
 	case NETDEV_BONDING_FAILOVER:
 	case NETDEV_PRE_UP:
-- 
2.53.0-Meta