[PATCH 4.14 19/66] Bluetooth: btsdio: fix use after free bug in btsdio_remove due to unfinished work

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Zheng Wang <zyytlz.wz@163.com>

[ Upstream commit 1e9ac114c4428fdb7ff4635b45d4f46017e8916f ]

In btsdio_probe, &data->work was bound with btsdio_work.In
btsdio_send_frame, it was started by schedule_work.

If we call btsdio_remove with an unfinished job, there may
be a race condition and cause UAF bug on hdev.

Fixes: ddbaf13e3609 ("[Bluetooth] Add generic driver for Bluetooth SDIO devices")
Signed-off-by: Zheng Wang <zyytlz.wz@163.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/bluetooth/btsdio.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/bluetooth/btsdio.c b/drivers/bluetooth/btsdio.c
index 20142bc77554c..bd55bf7a9914c 100644
--- a/drivers/bluetooth/btsdio.c
+++ b/drivers/bluetooth/btsdio.c
@@ -353,6 +353,7 @@ static void btsdio_remove(struct sdio_func *func)
 
 	BT_DBG("func %p", func);
 
+	cancel_work_sync(&data->work);
 	if (!data)
 		return;
 
-- 
2.39.2