2015-08-28 13:44:00

by Frederic Danis

Subject: [PATCH] Bluetooth: hci_bcm: Fix crash on suspend

If bcm_suspend is called whithout device opened there is a crash as
it tries to use bdev->hu which is NULL.
Rename bcm_device_list_lock to bcm_device_lock as it does not only apply
to bcm_device_list.

Signed-off-by: Frederic Danis <[email protected]>
---
drivers/bluetooth/hci_bcm.c | 36 ++++++++++++++++++++++++++----------
1 file changed, 26 insertions(+), 10 deletions(-)

diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c
index 33ec097..835bfab 100644
--- a/drivers/bluetooth/hci_bcm.c
+++ b/drivers/bluetooth/hci_bcm.c
@@ -66,7 +66,7 @@ struct bcm_data {
};

/* List of BCM BT UART devices */
-static DEFINE_SPINLOCK(bcm_device_list_lock);
+static DEFINE_SPINLOCK(bcm_device_lock);
static LIST_HEAD(bcm_device_list);

static int bcm_set_baudrate(struct hci_uart *hu, unsigned int speed)
@@ -118,7 +118,7 @@ static int bcm_set_baudrate(struct hci_uart *hu, unsigned int speed)
return 0;
}

-/* bcm_device_exists should be protected by bcm_device_list_lock */
+/* bcm_device_exists should be protected by bcm_device_lock */
static bool bcm_device_exists(struct bcm_device *device)
{
struct list_head *p;
@@ -164,7 +164,7 @@ static int bcm_open(struct hci_uart *hu)

hu->priv = bcm;

- spin_lock(&bcm_device_list_lock);
+ spin_lock(&bcm_device_lock);
list_for_each(p, &bcm_device_list) {
struct bcm_device *dev = list_entry(p, struct bcm_device, list);

@@ -185,7 +185,7 @@ static int bcm_open(struct hci_uart *hu)
if (bcm->dev)
bcm_gpio_set_power(bcm->dev, true);

- spin_unlock(&bcm_device_list_lock);
+ spin_unlock(&bcm_device_lock);

return 0;
}
@@ -197,14 +197,14 @@ static int bcm_close(struct hci_uart *hu)
BT_DBG("hu %p", hu);

/* Protect bcm->dev against removal of the device or driver */
- spin_lock(&bcm_device_list_lock);
+ spin_lock(&bcm_device_lock);
if (bcm_device_exists(bcm->dev)) {
bcm_gpio_set_power(bcm->dev, false);
#ifdef CONFIG_PM_SLEEP
bcm->dev->hu = NULL;
#endif
}
- spin_unlock(&bcm_device_list_lock);
+ spin_unlock(&bcm_device_lock);

skb_queue_purge(&bcm->txq);
kfree_skb(bcm->rx_skb);
@@ -338,6 +338,11 @@ static int bcm_suspend(struct device *dev)

BT_DBG("suspend (%p): is_suspended %d", bdev, bdev->is_suspended);

+ spin_lock(&bcm_device_lock);
+
+ if (!bdev->hu)
+ goto unlock;
+
if (!bdev->is_suspended) {
hci_uart_set_flow_control(bdev->hu, true);

@@ -352,6 +357,9 @@ static int bcm_suspend(struct device *dev)
mdelay(15);
}

+unlock:
+ spin_unlock(&bcm_device_lock);
+
return 0;
}

@@ -362,6 +370,11 @@ static int bcm_resume(struct device *dev)

BT_DBG("resume (%p): is_suspended %d", bdev, bdev->is_suspended);

+ spin_lock(&bcm_device_lock);
+
+ if (!bdev->hu)
+ goto unlock;
+
if (bdev->device_wakeup) {
gpiod_set_value(bdev->device_wakeup, true);
BT_DBG("resume, delaying 15 ms");
@@ -375,6 +388,9 @@ static int bcm_resume(struct device *dev)
hci_uart_set_flow_control(bdev->hu, false);
}

+unlock:
+ spin_unlock(&bcm_device_lock);
+
return 0;
}
#endif
@@ -488,9 +504,9 @@ static int bcm_probe(struct platform_device *pdev)
dev_info(&pdev->dev, "%s device registered.\n", dev->name);

/* Place this instance on the device list */
- spin_lock(&bcm_device_list_lock);
+ spin_lock(&bcm_device_lock);
list_add_tail(&dev->list, &bcm_device_list);
- spin_unlock(&bcm_device_list_lock);
+ spin_unlock(&bcm_device_lock);

bcm_gpio_set_power(dev, false);

@@ -501,9 +517,9 @@ static int bcm_remove(struct platform_device *pdev)
{
struct bcm_device *dev = platform_get_drvdata(pdev);

- spin_lock(&bcm_device_list_lock);
+ spin_lock(&bcm_device_lock);
list_del(&dev->list);
- spin_unlock(&bcm_device_list_lock);
+ spin_unlock(&bcm_device_lock);

acpi_dev_remove_driver_gpios(ACPI_COMPANION(&pdev->dev));

--
1.9.1

2015-08-28 19:09:58

by Marcel Holtmann

Subject: Re: [PATCH] Bluetooth: hci_bcm: Fix crash on suspend

Hi Fred,

> If bcm_suspend is called whithout device opened there is a crash as
> it tries to use bdev->hu which is NULL.
> Rename bcm_device_list_lock to bcm_device_lock as it does not only apply
> to bcm_device_list.
>
> Signed-off-by: Frederic Danis <[email protected]>
> ---
> drivers/bluetooth/hci_bcm.c | 36 ++++++++++++++++++++++++++----------
> 1 file changed, 26 insertions(+), 10 deletions(-)

patch has been applied to bluetooth-next tree.

Regards

Marcel