ip6mr: Remove RTNL in ip6mr_rules_init() and ip6mr_net_init().

When ip6mr_free_table() is called from ip6mr_rules_init() or
ip6mr_net_init(), the netns is not yet published.

Thus, no device should have been registered, and
mroute_clean_tables() will not call mif6_delete(), so
unregister_netdevice_many() is unnecessary.

unregister_netdevice_many() does nothing if the list is empty,
but it requires RTNL due to the unconditional ASSERT_RTNL()
at the entry of unregister_netdevice_many_notify().

Let's remove unnecessary RTNL and ASSERT_RTNL() and instead
add WARN_ON_ONCE() in ip6mr_free_table().

Note that we use a local list for the new WARN_ON_ONCE() because
dev_kill_list passed from ip6mr_rules_exit_rtnl() may have some
devices when other ops->init() fails after ipmr durnig setup_net().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260604224712.3209821-14-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Kuniyuki Iwashima
2026-06-04 22:46:31 +00:00
committed by Jakub Kicinski
parent 2a798e8c71
commit 2290727b2f

View File

@@ -253,10 +253,7 @@ static int __net_init ip6mr_rules_init(struct net *net)
return 0;
err2:
rtnl_lock();
ip6mr_free_table(mrt, &dev_kill_list);
unregister_netdevice_many(&dev_kill_list);
rtnl_unlock();
err1:
fib_rules_unregister(ops);
return err;
@@ -272,7 +269,6 @@ static void __net_exit ip6mr_rules_exit_rtnl(struct net *net,
{
struct mr_table *mrt, *next;
ASSERT_RTNL();
list_for_each_entry_safe(mrt, next, &net->ipv6.mr6_tables, list) {
list_del_rcu(&mrt->list);
ip6mr_free_table(mrt, dev_kill_list);
@@ -345,8 +341,6 @@ static void __net_exit ip6mr_rules_exit_rtnl(struct net *net,
{
struct mr_table *mrt = rcu_dereference_protected(net->ipv6.mrt6, 1);
ASSERT_RTNL();
RCU_INIT_POINTER(net->ipv6.mrt6, NULL);
ip6mr_free_table(mrt, dev_kill_list);
}
@@ -427,15 +421,19 @@ static void ip6mr_free_table(struct mr_table *mrt,
struct list_head *dev_kill_list)
{
struct net *net = read_pnet(&mrt->net);
LIST_HEAD(ip6mr_dev_kill_list);
WARN_ON_ONCE(!mr_can_free_table(net));
timer_shutdown_sync(&mrt->ipmr_expire_timer);
mroute_clean_tables(mrt, MRT6_FLUSH_MIFS | MRT6_FLUSH_MIFS_STATIC |
MRT6_FLUSH_MFC | MRT6_FLUSH_MFC_STATIC,
dev_kill_list);
&ip6mr_dev_kill_list);
mr_table_free(mrt);
WARN_ON_ONCE(!net_initialized(net) && !list_empty(&ip6mr_dev_kill_list));
list_splice(&ip6mr_dev_kill_list, dev_kill_list);
}
#ifdef CONFIG_PROC_FS
@@ -1384,10 +1382,7 @@ static int __net_init ip6mr_net_init(struct net *net)
proc_cache_fail:
remove_proc_entry("ip6_mr_vif", net->proc_net);
proc_vif_fail:
rtnl_lock();
ip6mr_rules_exit_rtnl(net, &dev_kill_list);
unregister_netdevice_many(&dev_kill_list);
rtnl_unlock();
ip6mr_rules_exit(net);
#endif
ip6mr_rules_fail: