Commit 242d3a49 authored by WANG Cong's avatar WANG Cong Committed by David S. Miller
Browse files

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 2f460933
("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: default avatarDavid Ahern <dsahern@gmail.com>
Tested-by: default avatarDavid Ahern <dsahern@gmail.com>
Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 29cee56c

include/net/addrconf.h

+2 −0
Original line number Diff line number Diff line
@@ -20,6 +20,8 @@ 
#define ADDRCONF_TIMER_FUZZ		(HZ / 4)

#define ADDRCONF_TIMER_FUZZ_MAX		(HZ)



#define ADDRCONF_NOTIFY_PRIORITY	0



#include <linux/in.h>

#include <linux/in6.h>

net/ipv6/addrconf.c

+1 −0
Original line number Diff line number Diff line
@@ -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)

net/ipv6/route.c

+11 −2
Original line number Diff line number Diff line
@@ -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)

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