[PATCH 4.19 384/422] Bluetooth: hci_serdev: clear HCI_UART_PROTO_READY to avoid closing proto races

[Greg Kroah-Hartman]

From: Balakrishna Godavarthi <bgodavar@xxxxxxxxxxxxxx>

[ Upstream commit 7cf7846d27bfc9731e449857db3eec5e0e9701ba ]

Clearing HCI_UART_PROTO_READY will avoid usage of proto function pointers
before running the proto close function pointer. There is chance of kernel
crash, due to usage of non proto close function pointers after proto close.

Signed-off-by: Balakrishna Godavarthi <bgodavar@xxxxxxxxxxxxxx>
Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/bluetooth/hci_serdev.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/bluetooth/hci_serdev.c b/drivers/bluetooth/hci_serdev.c
index aa2543b3c2869..46e20444ba19b 100644
--- a/drivers/bluetooth/hci_serdev.c
+++ b/drivers/bluetooth/hci_serdev.c
@@ -368,6 +368,7 @@ void hci_uart_unregister_device(struct hci_uart *hu)
 {
 	struct hci_dev *hdev = hu->hdev;
 
+	clear_bit(HCI_UART_PROTO_READY, &hu->flags);
 	hci_unregister_dev(hdev);
 	hci_free_dev(hdev);
 
-- 
2.20.1