[PATCH] Bluetooth: btsdio: fix use after free bug in btsdio_remove due to race condition

[Zheng Wang]

In btsdio_probe, the data->work is bound with btsdio_work. It will be 
started in btsdio_send_frame.

If the btsdio_remove runs with a unfinished work, there may be a race 
condition that hdev is freed but used in btsdio_work. Fix it by 
canceling the work before do cleanup in btsdio_remove.

Signed-off-by: Zheng Wang <zyytlz.wz@xxxxxxx>
---
 drivers/bluetooth/btsdio.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/bluetooth/btsdio.c b/drivers/bluetooth/btsdio.c
index 795be33f2892..f19d31ee37ea 100644
--- a/drivers/bluetooth/btsdio.c
+++ b/drivers/bluetooth/btsdio.c
@@ -357,6 +357,7 @@ static void btsdio_remove(struct sdio_func *func)
 	if (!data)
 		return;
 
+	cancel_work_sync(&data->work);
 	hdev = data->hdev;
 
 	sdio_set_drvdata(func, NULL);
-- 
2.25.1