Hi Jesse,
> A race condition is triggered when usermode control is given to
> userspace before the kernel's MSFT query responds, resulting in an
> unexpected response to userspace's reset command.
>
> Issue can be observed in btmon:
> < HCI Command: Vendor (0x3f|0x001e) plen 2 #3 [hci0]
> 05 01 ..
> @ USER Open: bt_stack_manage (privileged) version 2.22 {0x0002} [hci0]
> < HCI Command: Reset (0x03|0x0003) plen 0 #4 [hci0]
>> HCI Event: Command Complete (0x0e) plen 5 #5 [hci0]
> Vendor (0x3f|0x001e) ncmd 1
> Status: Command Disallowed (0x0c)
> 05 .
>> HCI Event: Command Complete (0x0e) plen 4 #6 [hci0]
> Reset (0x03|0x0003) ncmd 2
> Status: Success (0x00)
> Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
> Reviewed-by: Sonny Sasaka <sonnysasaka@xxxxxxxxxxxx>
> Signed-off-by: Jesse Melhuish <melhuishj@xxxxxxxxxxxx>
> ---
>
> Changes in v3:
> - Added guard around *_close calls as well.
>
> Changes in v2:
> - Moved guard to the new home for this code.
>
> net/bluetooth/hci_sync.c | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
patch has been applied to bluetooth-next tree.
Regards
Marcel
