[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: Ville Nuorvala <vnuorval@tcs.hut.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 25bc5ed4..fdf1a2f 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -215,11 +215,10 @@
* 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 @@
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 @@
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 @@
* 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 @@
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 @@
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;
+ 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) {
- if (t->dev != dev) {
- err = -EEXIST;
- break;
- }
+ 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 @@
break;
if (dev == ip6ip6_fb_tnl_dev) {
- if (copy_from_user(&p, ifr->ifr_ifru.ifru_data,
- sizeof (p))) {
- err = -EFAULT;
+ 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;
+ err = -EPERM;
+ if (t->dev == ip6ip6_fb_tnl_dev)
break;
- }
- } else {
- t = netdev_priv(dev);
+ dev = t->dev;
}
- err = unregister_netdevice(t->dev);
+ err = unregister_netdevice(dev);
break;
default:
err = -EINVAL;