[Bluetooth] More checks if DLC is still attached to the TTY
authorMarcel Holtmann <marcel@holtmann.org>
Mon, 8 Jan 2007 01:16:27 +0000 (02:16 +0100)
committerDavid S. Miller <davem@sunset.davemloft.net>
Tue, 9 Jan 2007 08:29:54 +0000 (00:29 -0800)
If the DLC device is no longer attached to the TTY device, then return
errors or default values for various callbacks of the TTY layer.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
net/bluetooth/rfcomm/tty.c

index e0e0d09023b2f0607e295397a699e5d7b2c55c25..eb2b52484c70e42e86cb329d093478cc225dab25 100644 (file)
@@ -697,9 +697,13 @@ static int rfcomm_tty_write_room(struct tty_struct *tty)
 
        BT_DBG("tty %p", tty);
 
+       if (!dev || !dev->dlc)
+               return 0;
+
        room = rfcomm_room(dev->dlc) - atomic_read(&dev->wmem_alloc);
        if (room < 0)
                room = 0;
+
        return room;
 }
 
@@ -915,12 +919,14 @@ static void rfcomm_tty_unthrottle(struct tty_struct *tty)
 static int rfcomm_tty_chars_in_buffer(struct tty_struct *tty)
 {
        struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
-       struct rfcomm_dlc *dlc = dev->dlc;
 
        BT_DBG("tty %p dev %p", tty, dev);
 
-       if (!skb_queue_empty(&dlc->tx_queue))
-               return dlc->mtu;
+       if (!dev || !dev->dlc)
+               return 0;
+
+       if (!skb_queue_empty(&dev->dlc->tx_queue))
+               return dev->dlc->mtu;
 
        return 0;
 }
@@ -928,11 +934,12 @@ static int rfcomm_tty_chars_in_buffer(struct tty_struct *tty)
 static void rfcomm_tty_flush_buffer(struct tty_struct *tty)
 {
        struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
-       if (!dev)
-               return;
 
        BT_DBG("tty %p dev %p", tty, dev);
 
+       if (!dev || !dev->dlc)
+               return;
+
        skb_queue_purge(&dev->dlc->tx_queue);
 
        if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags) && tty->ldisc.write_wakeup)
@@ -952,11 +959,12 @@ static void rfcomm_tty_wait_until_sent(struct tty_struct *tty, int timeout)
 static void rfcomm_tty_hangup(struct tty_struct *tty)
 {
        struct rfcomm_dev *dev = (struct rfcomm_dev *) tty->driver_data;
-       if (!dev)
-               return;
 
        BT_DBG("tty %p dev %p", tty, dev);
 
+       if (!dev)
+               return;
+
        rfcomm_tty_flush_buffer(tty);
 
        if (test_bit(RFCOMM_RELEASE_ONHUP, &dev->flags))