4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arkadiusz Bokowy <arkadiusz.bokowy@xxxxxxxxx> commit 92d4abd66f7080075793970fc8f241239e58a9e7 upstream. When the vhci device is opened in the two-step way, i.e.: open device then write a vendor packet with requested controller type, the device shall respond with a vendor packet which includes HCI index of created interface. When the virtual HCI is created, the host sends a reset request to the controller. This request is processed by the vhci_send_frame() function. However, this request is send by a different thread, so it might happen that this HCI request will be received before the vendor response is queued in the read queue. This results in the HCI vendor response and HCI reset request inversion in the read queue which leads to improper behavior of btvirt: > dmesg [1754256.640122] Bluetooth: MGMT ver 1.22 [1754263.023806] Bluetooth: MGMT ver 1.22 [1754265.043775] Bluetooth: hci1: Opcode 0x c03 failed: -110 In order to synchronize vhci two-step open/setup process with virtual HCI initialization, this patch adds internal lock when queuing data in the vhci_send_frame() function. Signed-off-by: Arkadiusz Bokowy <arkadiusz.bokowy@xxxxxxxxx> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/bluetooth/hci_vhci.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/bluetooth/hci_vhci.c +++ b/drivers/bluetooth/hci_vhci.c @@ -82,7 +82,10 @@ static int vhci_send_frame(struct hci_de struct vhci_data *data = hci_get_drvdata(hdev); memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1); + + mutex_lock(&data->open_mutex); skb_queue_tail(&data->readq, skb); + mutex_unlock(&data->open_mutex); wake_up_interruptible(&data->read_wait); return 0;
