From 242d3a49a2a1a71d8eb9f953db1bcaa9d698ce00 Mon Sep 17 00:00:00 2001 From: WANG Cong Date: Mon, 8 May 2017 10:12:13 -0700 Subject: [PATCH] ipv6: reorder ip6_route_dev_notifier after ipv6_dev_notf For each netns (except init_net), we initialize its null entry in 3 places: 1) The template itself, as we use kmemdup() 2) Code around dst_init_metrics() in ip6_route_net_init() 3) ip6_route_dev_notify(), which is supposed to initialize it after loopback registers Unfortunately the last one still happens in a wrong order because we expect to initialize net->ipv6.ip6_null_entry->rt6i_idev to net->loopback_dev's idev, thus we have to do that after we add idev to loopback. However, this notifier has priority == 0 same as ipv6_dev_notf, and ipv6_dev_notf is registered after ip6_route_dev_notifier so it is called actually after ip6_route_dev_notifier. This is similar to commit 2f460933f58e ("ipv6: initialize route null entry in addrconf_init()") which fixes init_net. Fix it by picking a smaller priority for ip6_route_dev_notifier. Also, we have to release the refcnt accordingly when unregistering loopback_dev because device exit functions are called before subsys exit functions. Acked-by: David Ahern Tested-by: David Ahern Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- include/net/addrconf.h | 2 ++ net/ipv6/addrconf.c | 1 + net/ipv6/route.c | 13 +++++++++++-- 3 files changed, 14 insertions(+), 2 deletions(-) diff --git a/include/net/addrconf.h b/include/net/addrconf.h index 2452e6449532..b43a4eec3cec 100644 --- a/include/net/addrconf.h +++ b/include/net/addrconf.h @@ -20,6 +20,8 @@ #define ADDRCONF_TIMER_FUZZ (HZ / 4) #define ADDRCONF_TIMER_FUZZ_MAX (HZ) +#define ADDRCONF_NOTIFY_PRIORITY 0 + #include #include diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 77a4bd526d6e..8d297a79b568 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -3548,6 +3548,7 @@ static int addrconf_notify(struct notifier_block *this, unsigned long event, */ static struct notifier_block ipv6_dev_notf = { .notifier_call = addrconf_notify, + .priority = ADDRCONF_NOTIFY_PRIORITY, }; static void addrconf_type_change(struct net_device *dev, unsigned long event) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 2f1136627dcb..dc61b0b5e64e 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -3709,7 +3709,10 @@ static int ip6_route_dev_notify(struct notifier_block *this, struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct net *net = dev_net(dev); - if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) { + if (!(dev->flags & IFF_LOOPBACK)) + return NOTIFY_OK; + + if (event == NETDEV_REGISTER) { net->ipv6.ip6_null_entry->dst.dev = dev; net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev); #ifdef CONFIG_IPV6_MULTIPLE_TABLES @@ -3717,6 +3720,12 @@ static int ip6_route_dev_notify(struct notifier_block *this, net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev); net->ipv6.ip6_blk_hole_entry->dst.dev = dev; net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev); +#endif + } else if (event == NETDEV_UNREGISTER) { + in6_dev_put(net->ipv6.ip6_null_entry->rt6i_idev); +#ifdef CONFIG_IPV6_MULTIPLE_TABLES + in6_dev_put(net->ipv6.ip6_prohibit_entry->rt6i_idev); + in6_dev_put(net->ipv6.ip6_blk_hole_entry->rt6i_idev); #endif } @@ -4024,7 +4033,7 @@ static struct pernet_operations ip6_route_net_late_ops = { static struct notifier_block ip6_route_dev_notifier = { .notifier_call = ip6_route_dev_notify, - .priority = 0, + .priority = ADDRCONF_NOTIFY_PRIORITY - 10, }; void __init ip6_route_init_special_entries(void) -- 2.30.2