Re: [PATCH] Bluetooth: hci_core: Fix poential Use-after-Free bug in hci_remove_adv_monitor

From: Luiz Augusto von Dentz
Date: Fri Feb 10 2023 - 14:53:42 EST


Hi Zheng,

On Thu, Feb 9, 2023 at 8:11 PM Zheng Wang <zyytlz.wz@xxxxxxx> wrote:
>
> In hci_remove_adv_monitor, if it gets into HCI_ADV_MONITOR_EXT_MSFT case,
> the function will free the monitor and print its handle after that.
>
> Fix it by switch the order.
>
> Fixes: 7cf5c2978f23 ("Bluetooth: hci_sync: Refactor remove Adv Monitor")
> Signed-off-by: Zheng Wang <zyytlz.wz@xxxxxxx>
> ---
> net/bluetooth/hci_core.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index b65c3aabcd53..db3352c60de6 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -1980,9 +1980,9 @@ static int hci_remove_adv_monitor(struct hci_dev *hdev,
> goto free_monitor;
>
> case HCI_ADV_MONITOR_EXT_MSFT:
> - status = msft_remove_monitor(hdev, monitor);
> bt_dev_dbg(hdev, "%s remove monitor %d msft status %d",
> hdev->name, monitor->handle, status);
> + status = msft_remove_monitor(hdev, monitor);

I wonder if it is not a good idea to move the logging inside
msft_remove_monitor?

> break;
> }
>
> --
> 2.25.1
>


--
Luiz Augusto von Dentz