From b82a26d8633cc89367fac75beb3ec33061bea44a Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sun, 7 Aug 2022 22:57:40 +0200 Subject: [PATCH] Bluetooth: hci_event: Fix vendor (unknown) opcode status handling Commit c8992cffbe74 ("Bluetooth: hci_event: Use of a function table to handle Command Complete") was (presumably) meant to only refactor things without any functional changes. But it does have one undesirable side-effect, before *status would always be set to skb->data[0] and it might be overridden by some of the opcode specific handling. While now it always set by the opcode specific handlers. This means that if the opcode is not known *status does not get set any more at all! This behavior change has broken bluetooth support for BCM4343A0 HCIs, the hci_bcm.c code tries to configure UART attached HCIs at a higher baudraute using vendor specific opcodes. The BCM4343A0 does not support this and this used to simply fail: [ 25.646442] Bluetooth: hci0: BCM: failed to write clock (-56) [ 25.646481] Bluetooth: hci0: Failed to set baudrate After which things would continue with the initial baudraute. But now that hci_cmd_complete_evt() no longer sets status for unknown opcodes *status is left at 0. This causes the hci_bcm.c code to think the baudraute has been changed on the HCI side and to also adjust the UART baudrate, after which communication with the HCI is broken, leading to: [ 28.579042] Bluetooth: hci0: command 0x0c03 tx timeout [ 36.961601] Bluetooth: hci0: BCM: Reset failed (-110) And non working bluetooth. Fix this by restoring the previous default "*status = skb->data[0]" handling for unknown opcodes. Fixes: c8992cffbe74 ("Bluetooth: hci_event: Use of a function table to handle Command Complete") Signed-off-by: Hans de Goede Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hci_event.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 485c814..73aa9ee 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -4179,6 +4179,17 @@ static void hci_cmd_complete_evt(struct hci_dev *hdev, void *data, } } + if (i == ARRAY_SIZE(hci_cc_table)) { + /* Unknown opcode, assume byte 0 contains the status, so + * that e.g. __hci_cmd_sync() properly returns errors + * for vendor specific commands send by HCI drivers. + * If a vendor doesn't actually follow this convention we may + * need to introduce a vendor CC table in order to properly set + * the status. + */ + *status = skb->data[0]; + } + handle_cmd_cnt_and_timer(hdev, ev->ncmd); hci_req_cmd_complete(hdev, *opcode, *status, req_complete, -- 2.7.4