[IRDA]: Fix rfcomm use-after-free

[pandora-kernel.git] / net / bluetooth / rfcomm / tty.c

diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c
index b2b1cce..22a8320 100644 (file)
--- a/net/bluetooth/rfcomm/tty.c
+++ b/net/bluetooth/rfcomm/tty.c
@@ -95,6 +95,10 @@ static void rfcomm_dev_destruct(struct rfcomm_dev *dev)
 
        BT_DBG("dev %p dlc %p", dev, dlc);
 
+       write_lock_bh(&rfcomm_dev_lock);
+       list_del_init(&dev->list);
+       write_unlock_bh(&rfcomm_dev_lock);
+
        rfcomm_dlc_lock(dlc);
        /* Detach DLC if it's owned by this dev */
        if (dlc->owner == dev)
@@ -156,8 +160,13 @@ static inline struct rfcomm_dev *rfcomm_dev_get(int id)
        read_lock(&rfcomm_dev_lock);
 
        dev = __rfcomm_dev_get(id);
-       if (dev)
-               rfcomm_dev_hold(dev);
+
+       if (dev) {
+               if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags))
+                       dev = NULL;
+               else
+                       rfcomm_dev_hold(dev);
+       }
 
        read_unlock(&rfcomm_dev_lock);
 
@@ -258,13 +267,20 @@ static int rfcomm_dev_add(struct rfcomm_dev_req *req, struct rfcomm_dlc *dlc)
 out:
        write_unlock_bh(&rfcomm_dev_lock);
 
-       if (err) {
+       if (err < 0) {
                kfree(dev);
                return err;
        }
 
        dev->tty_dev = tty_register_device(rfcomm_tty_driver, dev->id, NULL);
 
+       if (IS_ERR(dev->tty_dev)) {
+               err = PTR_ERR(dev->tty_dev);
+               list_del(&dev->list);
+               kfree(dev);
+               return err;
+       }
+
        return dev->id;
 }
 
@@ -272,10 +288,7 @@ static void rfcomm_dev_del(struct rfcomm_dev *dev)
 {
        BT_DBG("dev %p", dev);
 
-       write_lock_bh(&rfcomm_dev_lock);
-       list_del_init(&dev->list);
-       write_unlock_bh(&rfcomm_dev_lock);
-
+       set_bit(RFCOMM_TTY_RELEASED, &dev->flags);
        rfcomm_dev_put(dev);
 }
 
@@ -329,7 +342,7 @@ static int rfcomm_create_dev(struct sock *sk, void __user *arg)
        if (copy_from_user(&req, arg, sizeof(req)))
                return -EFAULT;
 
-       BT_DBG("sk %p dev_id %id flags 0x%x", sk, req.dev_id, req.flags);
+       BT_DBG("sk %p dev_id %d flags 0x%x", sk, req.dev_id, req.flags);
 
        if (req.flags != NOCAP_FLAGS && !capable(CAP_NET_ADMIN))
                return -EPERM;
@@ -370,7 +383,7 @@ static int rfcomm_release_dev(void __user *arg)
        if (copy_from_user(&req, arg, sizeof(req)))
                return -EFAULT;
 
-       BT_DBG("dev_id %id flags 0x%x", req.dev_id, req.flags);
+       BT_DBG("dev_id %d flags 0x%x", req.dev_id, req.flags);
 
        if (!(dev = rfcomm_dev_get(req.dev_id)))
                return -ENODEV;
@@ -383,6 +396,10 @@ static int rfcomm_release_dev(void __user *arg)
        if (req.flags & (1 << RFCOMM_HANGUP_NOW))
                rfcomm_dlc_close(dev->dlc, 0);
 
+       /* Shut down TTY synchronously before freeing rfcomm_dev */
+       if (dev->tty)
+               tty_vhangup(dev->tty);
+
        rfcomm_dev_del(dev);
        rfcomm_dev_put(dev);
        return 0;
@@ -415,6 +432,8 @@ static int rfcomm_get_dev_list(void __user *arg)
 
        list_for_each(p, &rfcomm_dev_list) {
                struct rfcomm_dev *dev = list_entry(p, struct rfcomm_dev, list);
+               if (test_bit(RFCOMM_TTY_RELEASED, &dev->flags))
+                       continue;
                (di + n)->id      = dev->id;
                (di + n)->flags   = dev->flags;
                (di + n)->state   = dev->dlc->state;