ipv6 sit: Avoid extra need for compat layer in PRL management.
YOSHIFUJI Hideaki [Mon, 16 Jun 2008 23:48:20 +0000 (16:48 -0700)]
We've introduced extra need of compat layer for ip_tunnel_prl{}
for PRL (Potential Router List) management.  Though compat_ioctl
is still missing in ipv4/ipv6, let's make the interface more
straight-forward and eliminate extra need for nasty compat layer
anyway since the interface is new for 2.6.26.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/if_tunnel.h
net/ipv6/sit.c

index f1fbe9c..d4efe40 100644 (file)
@@ -41,7 +41,7 @@ struct ip_tunnel_prl {
        __u16                   __reserved;
        __u32                   datalen;
        __u32                   __reserved2;
-       void __user             *data;
+       /* data follows */
 };
 
 /* PRL flags */
index 3de6ffd..32e871a 100644 (file)
@@ -222,15 +222,18 @@ __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
 
 }
 
-static int ipip6_tunnel_get_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
+static int ipip6_tunnel_get_prl(struct ip_tunnel *t,
+                               struct ip_tunnel_prl __user *a)
 {
-       struct ip_tunnel_prl *kp;
+       struct ip_tunnel_prl kprl, *kp;
        struct ip_tunnel_prl_entry *prl;
        unsigned int cmax, c = 0, ca, len;
        int ret = 0;
 
-       cmax = a->datalen / sizeof(*a);
-       if (cmax > 1 && a->addr != htonl(INADDR_ANY))
+       if (copy_from_user(&kprl, a, sizeof(kprl)))
+               return -EFAULT;
+       cmax = kprl.datalen / sizeof(kprl);
+       if (cmax > 1 && kprl.addr != htonl(INADDR_ANY))
                cmax = 1;
 
        /* For simple GET or for root users,
@@ -261,26 +264,25 @@ static int ipip6_tunnel_get_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
        for (prl = t->prl; prl; prl = prl->next) {
                if (c > cmax)
                        break;
-               if (a->addr != htonl(INADDR_ANY) && prl->addr != a->addr)
+               if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr)
                        continue;
                kp[c].addr = prl->addr;
                kp[c].flags = prl->flags;
                c++;
-               if (a->addr != htonl(INADDR_ANY))
+               if (kprl.addr != htonl(INADDR_ANY))
                        break;
        }
 out:
        read_unlock(&ipip6_lock);
 
        len = sizeof(*kp) * c;
-       ret = len ? copy_to_user(a->data, kp, len) : 0;
+       ret = 0;
+       if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen))
+               ret = -EFAULT;
 
        kfree(kp);
-       if (ret)
-               return -EFAULT;
 
-       a->datalen = len;
-       return 0;
+       return ret;
 }
 
 static int
@@ -873,11 +875,20 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
                break;
 
        case SIOCGETPRL:
+               err = -EINVAL;
+               if (dev == sitn->fb_tunnel_dev)
+                       goto done;
+               err = -ENOENT;
+               if (!(t = netdev_priv(dev)))
+                       goto done;
+               err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
+               break;
+
        case SIOCADDPRL:
        case SIOCDELPRL:
        case SIOCCHGPRL:
                err = -EPERM;
-               if (cmd != SIOCGETPRL && !capable(CAP_NET_ADMIN))
+               if (!capable(CAP_NET_ADMIN))
                        goto done;
                err = -EINVAL;
                if (dev == sitn->fb_tunnel_dev)
@@ -890,12 +901,6 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
                        goto done;
 
                switch (cmd) {
-               case SIOCGETPRL:
-                       err = ipip6_tunnel_get_prl(t, &prl);
-                       if (!err && copy_to_user(ifr->ifr_ifru.ifru_data,
-                                                &prl, sizeof(prl)))
-                               err = -EFAULT;
-                       break;
                case SIOCDELPRL:
                        err = ipip6_tunnel_del_prl(t, &prl);
                        break;
@@ -904,8 +909,7 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
                        err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
                        break;
                }
-               if (cmd != SIOCGETPRL)
-                       netdev_state_change(dev);
+               netdev_state_change(dev);
                break;
 
        default: