[Bluetooth] More checks if DLC is still attached to the TTY
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>
diff --git a/net/bluetooth/rfcomm/tty.c b/net/bluetooth/rfcomm/tty.c
index e0e0d09..eb2b524 100644
--- a/net/bluetooth/rfcomm/tty.c
+++ b/net/bluetooth/rfcomm/tty.c
@@ -697,9 +697,13 @@
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 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 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_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))
