Re: [PATCH -next v2] xhci: fix two places when dealing with return value of function xhci_check_args

From: Mathias Nyman
Date: Thu Feb 10 2022 - 03:18:00 EST


On 10.2.2022 3.04, 谢泓宇 wrote:
> Hi,
>
> On 2022/2/9 17:29, Mathias Nyman wrote:
>> On 9.2.2022 4.52, Hongyu Xie wrote:
>>> From: Hongyu Xie <xiehongyu1@xxxxxxxxxx>
>>>
>>> xhci_check_args returns 4 types of value, -ENODEV, -EINVAL, 1 and 0.
>>> xhci_urb_enqueue and xhci_check_streams_endpoint return -EINVAL if
>>> the return value of xhci_check_args <= 0.
>>> This will cause a problem.
>>> For example, r8152_submit_rx calling usb_submit_urb in
>>> drivers/net/usb/r8152.c.
>>> r8152_submit_rx will never get -ENODEV after submiting an urb
>>> when xHC is halted,
>>> because xhci_urb_enqueue returns -EINVAL in the very beginning.
>>>
>>> Fixes: 203a86613fb3 ("xhci: Avoid NULL pointer deref when host dies.")
>>> Cc: stable@xxxxxxxxxxxxxxx
>>> Signed-off-by: Hongyu Xie <xiehongyu1@xxxxxxxxxx>
>>> ---
>> Thanks, added to queue.
>> Changed the commit message and header a bit:
>>
>> "xhci: Prevent futile URB re-submissions due to incorrect return value.
>>      The -ENODEV return value from xhci_check_args() is incorrectly changed
>> to -EINVAL in a couple places before propagated further.
>>      xhci_check_args() returns 4 types of value, -ENODEV, -EINVAL, 1 and 0.
>> xhci_urb_enqueue and xhci_check_streams_endpoint return -EINVAL if
>> the return value of xhci_check_args <= 0.
>> This causes problems for example r8152_submit_rx, calling usb_submit_urb
>> in drivers/net/usb/r8152.c.
>> r8152_submit_rx will never get -ENODEV after submiting an urb when xHC
>> is halted because xhci_urb_enqueue returns -EINVAL in the very beginning."
>>
>> Let me know if you disagree with this.
>>
>> Thanks
>> -Mathias
>
> Sounds good to me.
>
> Do I have to send another patch with commit message and header changed?
>
> Thanks
>
> Hongyu Xie
>

No need, I'll submit it.

-Mathias