Commit 567131a7 authored by Ville Nuorvala's avatar Ville Nuorvala Committed by David S. Miller
Browse files

[IPV6]: Fix SIOCCHGTUNNEL bug in IPv6 tunnels 



A logic bug in tunnel lookup could result in duplicate tunnels when
changing an existing device.

Signed-off-by: default avatarVille Nuorvala <vnuorval@tcs.hut.fi>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e94ef682

net/ipv6/ip6_tunnel.c

+46 −65
Original line number Diff line number Diff line
@@ -215,11 +215,10 @@ ip6ip6_tnl_unlink(struct ip6_tnl *t) 
 *   Create tunnel matching given parameters.

 * 

 * Return: 

 *   0 on success

 *   created tunnel or NULL

 **/



static int

ip6_tnl_create(struct ip6_tnl_parm *p, struct ip6_tnl **pt)

static struct ip6_tnl *ip6_tnl_create(struct ip6_tnl_parm *p)

{

	struct net_device *dev;

	struct ip6_tnl *t;
@@ -236,11 +235,11 @@ ip6_tnl_create(struct ip6_tnl_parm *p, struct ip6_tnl **pt) 
				break;

		}

		if (i == IP6_TNL_MAX) 

			return -ENOBUFS;

			goto failed;

	}

	dev = alloc_netdev(sizeof (*t), name, ip6ip6_tnl_dev_setup);

	if (dev == NULL)

		return -ENOMEM;

		goto failed;



	t = netdev_priv(dev);

	dev->init = ip6ip6_tnl_dev_init;
@@ -248,13 +247,13 @@ ip6_tnl_create(struct ip6_tnl_parm *p, struct ip6_tnl **pt) 


	if ((err = register_netdevice(dev)) < 0) {

		free_netdev(dev);

		return err;

		goto failed;

	}

	dev_hold(dev);



	ip6ip6_tnl_link(t);

	*pt = t;

	return 0;

	return t;

failed:

	return NULL;

}



/**
@@ -268,32 +267,23 @@ ip6_tnl_create(struct ip6_tnl_parm *p, struct ip6_tnl **pt) 
 *   tunnel device is created and registered for use.

 *

 * Return:

 *   0 if tunnel located or created,

 *   -EINVAL if parameters incorrect,

 *   -ENODEV if no matching tunnel available

 *   matching tunnel or NULL

 **/



static int

ip6ip6_tnl_locate(struct ip6_tnl_parm *p, struct ip6_tnl **pt, int create)

static struct ip6_tnl *ip6ip6_tnl_locate(struct ip6_tnl_parm *p, int create)

{

	struct in6_addr *remote = &p->raddr;

	struct in6_addr *local = &p->laddr;

	struct ip6_tnl *t;



	if (p->proto != IPPROTO_IPV6)

		return -EINVAL;



	for (t = *ip6ip6_bucket(p); t; t = t->next) {

		if (ipv6_addr_equal(local, &t->parms.laddr) &&

		    ipv6_addr_equal(remote, &t->parms.raddr)) {

			*pt = t;

			return (create ? -EEXIST : 0);

		}

		    ipv6_addr_equal(remote, &t->parms.raddr))

			return t;

	}

	if (!create)

		return -ENODEV;

	

	return ip6_tnl_create(p, pt);

		return NULL;

	return ip6_tnl_create(p);

}



/**
@@ -920,26 +910,20 @@ static int 
ip6ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)

{

	int err = 0;

	int create;

	struct ip6_tnl_parm p;

	struct ip6_tnl *t = NULL;



	switch (cmd) {

	case SIOCGETTUNNEL:

		if (dev == ip6ip6_fb_tnl_dev) {

			if (copy_from_user(&p,

					   ifr->ifr_ifru.ifru_data,

					   sizeof (p))) {

			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) {

				err = -EFAULT;

				break;

			}

			if ((err = ip6ip6_tnl_locate(&p, &t, 0)) == -ENODEV)

				t = netdev_priv(dev);

			else if (err)

				break;

		} else

			t = ip6ip6_tnl_locate(&p, 0);

		}

		if (t == NULL)

			t = netdev_priv(dev);



		memcpy(&p, &t->parms, sizeof (p));

		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof (p))) {

			err = -EFAULT;
@@ -948,35 +932,36 @@ ip6ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 
	case SIOCADDTUNNEL:

	case SIOCCHGTUNNEL:

		err = -EPERM;

		create = (cmd == SIOCADDTUNNEL);

		if (!capable(CAP_NET_ADMIN))

			break;

		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p))) {

		err = -EFAULT;

		if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))

			break;

		}

		if (!create && dev != ip6ip6_fb_tnl_dev) {

			t = netdev_priv(dev);

		}

		if (!t && (err = ip6ip6_tnl_locate(&p, &t, create))) {

		err = -EINVAL;

		if (p.proto != IPPROTO_IPV6)

			break;

		}

		if (cmd == SIOCCHGTUNNEL) {

		t = ip6ip6_tnl_locate(&p, cmd == SIOCADDTUNNEL);

		if (dev != ip6ip6_fb_tnl_dev && cmd == SIOCCHGTUNNEL) {

			if (t != NULL) {

				if (t->dev != dev) {

					err = -EEXIST;

					break;

				}

			} else

				t = netdev_priv(dev);



			ip6ip6_tnl_unlink(t);

			err = ip6ip6_tnl_change(t, &p);

			ip6ip6_tnl_link(t);

			netdev_state_change(dev);

		}

		if (copy_to_user(ifr->ifr_ifru.ifru_data,

				 &t->parms, sizeof (p))) {

			err = -EFAULT;

		} else {

		if (t) {

			err = 0;

		}

			if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof (p)))

				err = -EFAULT;



		} else

			err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);

		break;

	case SIOCDELTUNNEL:

		err = -EPERM;
@@ -984,22 +969,18 @@ ip6ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) 
			break;



		if (dev == ip6ip6_fb_tnl_dev) {

			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data,

					   sizeof (p))) {

			err = -EFAULT;

			if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))

				break;

			}

			err = ip6ip6_tnl_locate(&p, &t, 0);

			if (err)

			err = -ENOENT;

			if ((t = ip6ip6_tnl_locate(&p, 0)) == NULL)

				break;

			if (t == netdev_priv(ip6ip6_fb_tnl_dev)) {

			err = -EPERM;

			if (t->dev == ip6ip6_fb_tnl_dev)

				break;

			dev = t->dev;

		}

		} else {

			t = netdev_priv(dev);

		}

		err = unregister_netdevice(t->dev);

		err = unregister_netdevice(dev);

		break;

	default:

		err = -EINVAL;