From 68d39ea5e0adc9ecaea1ce8abd842ec972eb8718 Mon Sep 17 00:00:00 2001 From: Jonathan Rissanen Date: Fri, 27 Mar 2026 11:47:20 +0100 Subject: [PATCH] Bluetooth: hci_ldisc: Clear HCI_UART_PROTO_INIT on error When hci_register_dev() fails in hci_uart_register_dev() HCI_UART_PROTO_INIT is not cleared before calling hu->proto->close(hu) and setting hu->hdev to NULL. This means incoming UART data will reach the protocol-specific recv handler in hci_uart_tty_receive() after resources are freed. Clear HCI_UART_PROTO_INIT with a write lock before calling hu->proto->close() and setting hu->hdev to NULL. The write lock ensures all active readers have completed and no new reader can enter the protocol recv path before resources are freed. This allows the protocol-specific recv functions to remove the "HCI_UART_REGISTERED" guard without risking a null pointer dereference if hci_register_dev() fails. Fixes: 5df5dafc171b ("Bluetooth: hci_uart: Fix another race during initialization") Signed-off-by: Jonathan Rissanen Signed-off-by: Luiz Augusto von Dentz --- drivers/bluetooth/hci_ldisc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c index 71c1997a0f73..275ea865bc29 100644 --- a/drivers/bluetooth/hci_ldisc.c +++ b/drivers/bluetooth/hci_ldisc.c @@ -692,6 +692,9 @@ static int hci_uart_register_dev(struct hci_uart *hu) if (hci_register_dev(hdev) < 0) { BT_ERR("Can't register HCI device"); + percpu_down_write(&hu->proto_lock); + clear_bit(HCI_UART_PROTO_INIT, &hu->flags); + percpu_up_write(&hu->proto_lock); hu->proto->close(hu); hu->hdev = NULL; hci_free_dev(hdev);