diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2025-01-06 10:07:49 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-01-08 04:49:19 +0300 |
| commit | a239e0625097bccdd4065390952fe9e6d0fdf02b (patch) | |
| tree | c837fe82812876a2931999f753435b20cfe80977 | |
| parent | 4ce1aeece911c7fe3ac6afb96dbc2c6ef20da639 (diff) | |
| download | linux-a239e0625097bccdd4065390952fe9e6d0fdf02b.tar.xz | |
net: Hold __rtnl_net_lock() in (un)?register_netdevice_notifier().
(un)?register_netdevice_notifier() hold pernet_ops_rwsem and RTNL,
iterate all netns, and trigger the notifier for all netdev.
Let's hold __rtnl_net_lock() before triggering the notifier.
Note that we will need protection for netdev_chain when RTNL is
removed. (e.g. blocking_notifier conversion [0] with a lockdep
annotation [1])
Link: https://lore.kernel.org/netdev/20250104063735.36945-2-kuniyu@amazon.com/ [0]
Link: https://lore.kernel.org/netdev/20250105075957.67334-1-kuniyu@amazon.com/ [1]
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250106070751.63146-2-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/core/dev.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 2179da3dfffc..34ded7974675 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1769,14 +1769,19 @@ int register_netdevice_notifier(struct notifier_block *nb) /* Close race with setup_net() and cleanup_net() */ down_write(&pernet_ops_rwsem); + + /* When RTNL is removed, we need protection for netdev_chain. */ rtnl_lock(); + err = raw_notifier_chain_register(&netdev_chain, nb); if (err) goto unlock; if (dev_boot_phase) goto unlock; for_each_net(net) { + __rtnl_net_lock(net); err = call_netdevice_register_net_notifiers(nb, net); + __rtnl_net_unlock(net); if (err) goto rollback; } @@ -1787,8 +1792,11 @@ unlock: return err; rollback: - for_each_net_continue_reverse(net) + for_each_net_continue_reverse(net) { + __rtnl_net_lock(net); call_netdevice_unregister_net_notifiers(nb, net); + __rtnl_net_unlock(net); + } raw_notifier_chain_unregister(&netdev_chain, nb); goto unlock; @@ -1821,8 +1829,11 @@ int unregister_netdevice_notifier(struct notifier_block *nb) if (err) goto unlock; - for_each_net(net) + for_each_net(net) { + __rtnl_net_lock(net); call_netdevice_unregister_net_notifiers(nb, net); + __rtnl_net_unlock(net); + } unlock: rtnl_unlock(); |