[PATCH 2/2] Bluetooth: hci_intel: add missing tty-device sanity check

From: Johan Hovold
Date: Wed Mar 29 2017 - 12:17:03 EST


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@xxxxxxxxxxxxxxx> # 4.3
Cc: Loic Poulain <loic.poulain@xxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
---
drivers/bluetooth/hci_intel.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/bluetooth/hci_intel.c b/drivers/bluetooth/hci_intel.c
index 9e271286c5e5..73306384af6c 100644
--- 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) {
@@ -889,6 +895,8 @@ static int intel_setup(struct hci_uart *hu)
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);
@@ -1056,6 +1064,9 @@ 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.
*/
@@ -1072,7 +1083,7 @@ 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;
--
2.12.2