Commit db44575f authored by Alexey Kuznetsov's avatar Alexey Kuznetsov Committed by David S. Miller
Browse files

[NET]: fix oops after tunnel module unload 



Tunnel modules used to obtain module refcount each time when
some tunnel was created, which meaned that tunnel could be unloaded
only after all the tunnels are deleted.

Since killing old MOD_*_USE_COUNT macros this protection has gone.
It is possible to return it back as module_get/put, but it looks
more natural and practically useful to force destruction of all
the child tunnels on module unload.

Signed-off-by: default avatarAlexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1f494c0e

net/ipv4/ip_gre.c

+18 −3
Original line number Diff line number Diff line
@@ -290,7 +290,6 @@ static struct ip_tunnel * ipgre_tunnel_locate(struct ip_tunnel_parm *parms, int 


	dev_hold(dev);

	ipgre_tunnel_link(nt);

	/* Do not decrement MOD_USE_COUNT here. */

	return nt;



failed:
@@ -1277,12 +1276,28 @@ err1: 
	goto out;

}



static void ipgre_fini(void)

static void __exit ipgre_destroy_tunnels(void)

{

	int prio;



	for (prio = 0; prio < 4; prio++) {

		int h;

		for (h = 0; h < HASH_SIZE; h++) {

			struct ip_tunnel *t;

			while ((t = tunnels[prio][h]) != NULL)

				unregister_netdevice(t->dev);

		}

	}

}



static void __exit ipgre_fini(void)

{

	if (inet_del_protocol(&ipgre_protocol, IPPROTO_GRE) < 0)

		printk(KERN_INFO "ipgre close: can't remove protocol\n");



	unregister_netdev(ipgre_fb_tunnel_dev);

	rtnl_lock();

	ipgre_destroy_tunnels();

	rtnl_unlock();

}



module_init(ipgre_init);

net/ipv4/ipip.c

+18 −2
Original line number Diff line number Diff line
@@ -255,7 +255,6 @@ static struct ip_tunnel * ipip_tunnel_locate(struct ip_tunnel_parm *parms, int c 


	dev_hold(dev);

	ipip_tunnel_link(nt);

	/* Do not decrement MOD_USE_COUNT here. */

	return nt;



failed:
@@ -920,12 +919,29 @@ static int __init ipip_init(void) 
	goto out;

}



static void __exit ipip_destroy_tunnels(void)

{

	int prio;



	for (prio = 1; prio < 4; prio++) {

		int h;

		for (h = 0; h < HASH_SIZE; h++) {

			struct ip_tunnel *t;

			while ((t = tunnels[prio][h]) != NULL)

				unregister_netdevice(t->dev);

		}

	}

}



static void __exit ipip_fini(void)

{

	if (ipip_unregister() < 0)

		printk(KERN_INFO "ipip close: can't deregister tunnel\n");



	unregister_netdev(ipip_fb_tunnel_dev);

	rtnl_lock();

	ipip_destroy_tunnels();

	unregister_netdevice(ipip_fb_tunnel_dev);

	rtnl_unlock();

}



module_init(ipip_init);

net/ipv6/sit.c

+19 −2
Original line number Diff line number Diff line
@@ -195,7 +195,6 @@ static struct ip_tunnel * ipip6_tunnel_locate(struct ip_tunnel_parm *parms, int 
	dev_hold(dev);



	ipip6_tunnel_link(nt);

	/* Do not decrement MOD_USE_COUNT here. */

	return nt;



failed:
@@ -794,10 +793,28 @@ static struct net_protocol sit_protocol = { 
	.err_handler	=	ipip6_err,

};



static void __exit sit_destroy_tunnels(void)

{

	int prio;



	for (prio = 1; prio < 4; prio++) {

		int h;

		for (h = 0; h < HASH_SIZE; h++) {

			struct ip_tunnel *t;

			while ((t = tunnels[prio][h]) != NULL)

				unregister_netdevice(t->dev);

		}

	}

}



void __exit sit_cleanup(void)

{

	inet_del_protocol(&sit_protocol, IPPROTO_IPV6);

	unregister_netdev(ipip6_fb_tunnel_dev);



	rtnl_lock();

	sit_destroy_tunnels();

	unregister_netdevice(ipip6_fb_tunnel_dev);

	rtnl_unlock();

}



int __init sit_init(void)

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