Bluetooth: hci_intel: add missing tty-device sanity check

Make sure to check the tty-device pointer before looking up the sibling
platform device to avoid dereferencing a NULL-pointer when the tty is
one end of a Unix98 pty.

Fixes: 74cdad37cd24 ("Bluetooth: hci_intel: Add runtime PM support")
Fixes: 1ab1f239bf17 ("Bluetooth: hci_intel: Add support for platform driver")
Cc: stable <stable@vger.kernel.org>     # 4.3
Cc: Loic Poulain <loic.poulain@intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/drivers/bluetooth/hci_intel.c b/drivers/bluetooth/hci_intel.c
index d915e7eee233e11c67b9ca15c169e439a871ebef..fa5099986f1b3ca50c14745990a0fe682963b737 100644 (file)
--- a/drivers/bluetooth/hci_intel.c
+++ b/drivers/bluetooth/hci_intel.c
@@ -307,6 +307,9 @@ static int intel_set_power(struct hci_uart *hu, bool powered)
        struct list_head *p;
        int err = -ENODEV;
 
+       if (!hu->tty->dev)
+               return err;
+
        mutex_lock(&intel_device_list_lock);
 
        list_for_each(p, &intel_device_list) {
@@ -379,6 +382,9 @@ static void intel_busy_work(struct work_struct *work)
        struct intel_data *intel = container_of(work, struct intel_data,
                                                busy_work);
 
+       if (!intel->hu->tty->dev)
+               return;
+
        /* Link is busy, delay the suspend */
        mutex_lock(&intel_device_list_lock);
        list_for_each(p, &intel_device_list) {
@@ -899,6 +905,8 @@ done:
        list_for_each(p, &intel_device_list) {
                struct intel_device *dev = list_entry(p, struct intel_device,
                                                      list);
+               if (!hu->tty->dev)
+                       break;
                if (hu->tty->dev->parent == dev->pdev->dev.parent) {
                        if (device_may_wakeup(&dev->pdev->dev)) {
                                set_bit(STATE_LPM_ENABLED, &intel->flags);
@@ -1066,6 +1074,9 @@ static int intel_enqueue(struct hci_uart *hu, struct sk_buff *skb)
 
        BT_DBG("hu %p skb %p", hu, skb);
 
+       if (!hu->tty->dev)
+               goto out_enqueue;
+
        /* Be sure our controller is resumed and potential LPM transaction
         * completed before enqueuing any packet.
         */
@@ -1082,7 +1093,7 @@ static int intel_enqueue(struct hci_uart *hu, struct sk_buff *skb)
                }
        }
        mutex_unlock(&intel_device_list_lock);
-
+out_enqueue:
        skb_queue_tail(&intel->txq, skb);
 
        return 0;