1 files changed, 31 insertions, 39 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 11a0ba47b677..42b6c6319bc2 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -486,12 +486,14 @@ static unsigned int tun_chr_poll(struct file *file, poll_table * wait)
 {
         struct tun_file *tfile = file->private_data;
         struct tun_struct *tun = __tun_get(tfile);
-        struct sock *sk = tun->sk;
+        struct sock *sk;
         unsigned int mask = 0;
 
         if (!tun)
                 return POLLERR;
 
+        sk = tun->sk;
+
         DBG(KERN_INFO "%s: tun_chr_poll\n", tun->dev->name);
 
         poll_wait(file, &tun->socket.wait, wait);
@@ -1046,20 +1048,15 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
         return err;
 }
 
-static int tun_get_iff(struct net *net, struct file *file, struct ifreq *ifr)
+static int tun_get_iff(struct net *net, struct tun_struct *tun,
+                       struct ifreq *ifr)
 {
-        struct tun_struct *tun = tun_get(file);
-
-        if (!tun)
-                return -EBADFD;
-
         DBG(KERN_INFO "%s: tun_get_iff\n", tun->dev->name);
 
         strcpy(ifr->ifr_name, tun->dev->name);
 
         ifr->ifr_flags = tun_flags(tun);
 
-        tun_put(tun);
         return 0;
 }
 
@@ -1103,8 +1100,8 @@ static int set_offload(struct net_device *dev, unsigned long arg)
         return 0;
 }
 
-static int tun_chr_ioctl(struct inode *inode, struct file *file,
-                         unsigned int cmd, unsigned long arg)
+static long tun_chr_ioctl(struct file *file, unsigned int cmd,
+                          unsigned long arg)
 {
         struct tun_file *tfile = file->private_data;
         struct tun_struct *tun;
@@ -1126,34 +1123,32 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
                                 (unsigned int __user*)argp);
         }
 
+        rtnl_lock();
+
         tun = __tun_get(tfile);
         if (cmd == TUNSETIFF && !tun) {
-                int err;
-
                 ifr.ifr_name[IFNAMSIZ-1] = '\0';
 
-                rtnl_lock();
-                err = tun_set_iff(tfile->net, file, &ifr);
-                rtnl_unlock();
+                ret = tun_set_iff(tfile->net, file, &ifr);
 
-                if (err)
-                        return err;
+                if (ret)
+                        goto unlock;
 
                 if (copy_to_user(argp, &ifr, sizeof(ifr)))
-                        return -EFAULT;
-                return 0;
+                        ret = -EFAULT;
+                goto unlock;
         }
 
-
+        ret = -EBADFD;
         if (!tun)
-                return -EBADFD;
+                goto unlock;
 
         DBG(KERN_INFO "%s: tun_chr_ioctl cmd %d\n", tun->dev->name, cmd);
 
         ret = 0;
         switch (cmd) {
         case TUNGETIFF:
-                ret = tun_get_iff(current->nsproxy->net_ns, file, &ifr);
+                ret = tun_get_iff(current->nsproxy->net_ns, tun, &ifr);
                 if (ret)
                         break;
 
@@ -1199,7 +1194,6 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
 
         case TUNSETLINK:
                 /* Only allow setting the type when the interface is down */
-                rtnl_lock();
                 if (tun->dev->flags & IFF_UP) {
                         DBG(KERN_INFO "%s: Linktype set failed because interface is up\n",
                                 tun->dev->name);
@@ -1209,7 +1203,6 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
                         DBG(KERN_INFO "%s: linktype set to %d\n", tun->dev->name, tun->dev->type);
                         ret = 0;
                 }
-                rtnl_unlock();
                 break;
 
 #ifdef TUN_DEBUG
@@ -1218,9 +1211,7 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
                 break;
 #endif
         case TUNSETOFFLOAD:
-                rtnl_lock();
                 ret = set_offload(tun->dev, arg);
-                rtnl_unlock();
                 break;
 
         case TUNSETTXFILTER:
@@ -1228,9 +1219,7 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
                 ret = -EINVAL;
                 if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)
                         break;
-                rtnl_lock();
                 ret = update_filter(&tun->txflt, (void __user *)arg);
-                rtnl_unlock();
                 break;
 
         case SIOCGIFHWADDR:
@@ -1246,9 +1235,7 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
                 DBG(KERN_DEBUG "%s: set hw address: %pM\n",
                         tun->dev->name, ifr.ifr_hwaddr.sa_data);
 
-                rtnl_lock();
                 ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
-                rtnl_unlock();
                 break;
 
         case TUNGETSNDBUF:
@@ -1271,7 +1258,10 @@ static int tun_chr_ioctl(struct inode *inode, struct file *file,
                 break;
         };
 
-        tun_put(tun);
+unlock:
+        rtnl_unlock();
+        if (tun)
+                tun_put(tun);
         return ret;
 }
 
@@ -1324,20 +1314,22 @@ static int tun_chr_close(struct inode *inode, struct file *file)
         struct tun_file *tfile = file->private_data;
         struct tun_struct *tun;
 
-
-        rtnl_lock();
         tun = __tun_get(tfile);
         if (tun) {
-                DBG(KERN_INFO "%s: tun_chr_close\n", tun->dev->name);
+                struct net_device *dev = tun->dev;
+
+                DBG(KERN_INFO "%s: tun_chr_close\n", dev->name);
 
                 __tun_detach(tun);
 
                 /* If desireable, unregister the netdevice. */
-                if (!(tun->flags & TUN_PERSIST))
-                        unregister_netdevice(tun->dev);
-
+                if (!(tun->flags & TUN_PERSIST)) {
+                        rtnl_lock();
+                        if (dev->reg_state == NETREG_REGISTERED)
+                                unregister_netdevice(dev);
+                        rtnl_unlock();
+                }
         }
-        rtnl_unlock();
 
         tun = tfile->tun;
         if (tun)
@@ -1357,7 +1349,7 @@ static const struct file_operations tun_fops = {
         .write = do_sync_write,
         .aio_write = tun_chr_aio_write,
         .poll   = tun_chr_poll,
-        .ioctl  = tun_chr_ioctl,
+        .unlocked_ioctl = tun_chr_ioctl,
         .open   = tun_chr_open,
         .release = tun_chr_close,
         .fasync = tun_chr_fasync