Re: [RFT PATCH v2] xhci: Fix memory leak when caching protocol extended capability PSI tables

From: Mathias Nyman
Date: Wed Feb 12 2020 - 03:59:41 EST


On 11.2.2020 18.13, Greg KH wrote:
> On Tue, Feb 11, 2020 at 04:12:40PM +0100, Marek Szyprowski wrote:
>> Hi Mathias,
>>
>> On 11.02.2020 16:01, Mathias Nyman wrote:
>>> xhci driver assumed that xHC controllers have at most one custom
>>> supported speed table (PSI) for all usb 3.x ports.
>>> Memory was allocated for one PSI table under the xhci hub structure.
>>>
>>> Turns out this is not the case, some controllers have a separate
>>> "supported protocol capability" entry with a PSI table for each port.
>>> This means each usb3 roothub port can in theory support different custom
>>> speeds.
>>>
>>> To solve this, cache all supported protocol capabilities with their PSI
>>> tables in an array, and add pointers to the xhci port structure so that
>>> every port points to its capability entry in the array.
>>>
>>> When creating the SuperSpeedPlus USB Device Capability BOS descriptor
>>> for the xhci USB 3.1 roothub we for now will use only data from the
>>> first USB 3.1 capable protocol capability entry in the array.
>>> This could be improved later, this patch focuses resolving
>>> the memory leak.
>>>
>>> Reported-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx>
>>> Reported-by: Sajja Venkateswara Rao <VenkateswaraRao.Sajja@xxxxxxx>
>>> Fixes: 47189098f8be ("xhci: parse xhci protocol speed ID list for usb 3.1 usage")
>>> Cc: stable <stable@xxxxxxxxxxxxxxx> # v4.4+
>>> Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
>>
>> Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
>
> Nice!
>
> Should I revert the first and then apply this?
>

Yes, please

Thanks

-Mathias