[RFC PATCH] Bluetooth: btusb: Fix memory leak in play_deferred

From: Jeffy Chen
Date: Thu Jun 22 2017 - 06:11:11 EST


Currently in play_deferred, we are calling usb_submit_urb directly to
submit deferred tx urb after unanchor it.

So the usb_giveback_urb_bh would failed to unref it in usb_unanchor_urb
and cause memory leak:
unreferenced object 0xffffffc0ce0fa400 (size 256):
...
backtrace:
[<ffffffc00034a9a8>] __save_stack_trace+0x48/0x6c
[<ffffffc00034b088>] create_object+0x138/0x254
[<ffffffc0009d5504>] kmemleak_alloc+0x58/0x8c
[<ffffffc000345f78>] __kmalloc+0x1d4/0x2a0
[<ffffffc0006765bc>] usb_alloc_urb+0x30/0x60
[<ffffffbffc128598>] alloc_ctrl_urb+0x38/0x120 [btusb]
[<ffffffbffc129e7c>] btusb_send_frame+0x64/0xf8 [btusb]

Use submit_tx_urb instead for better error handling and avoid the leak.

Signed-off-by: Jeffy Chen <jeffy.chen@xxxxxxxxxxxxxx>
---

drivers/bluetooth/btusb.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 278e811..b469f9b 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -3254,11 +3254,12 @@ static int btusb_suspend(struct usb_interface *intf, pm_message_t message)

static void play_deferred(struct btusb_data *data)
{
+ struct hci_dev *hdev = data->hdev;
struct urb *urb;
int err;

while ((urb = usb_get_from_anchor(&data->deferred))) {
- err = usb_submit_urb(urb, GFP_ATOMIC);
+ err = submit_tx_urb(hdev, urb);
if (err < 0)
break;

--
2.1.4