Star,
I agree they are optional. The description says
DataLength should be 0 and Data should be NULL for
the EfiUsbNoData case. That is why I did not think
Direction needed to be evaluated if DataLength must
be 0 in this case.
In fact, the Host Controller implementations return
an error if this is not the case:
if ((TransferDirection == EfiUsbNoData) &&
((Data != NULL) || (*DataLength != 0))) {
return EFI_INVALID_PARAMETER;
}
So I think the logic in the current patch is safe.
However, since there are questions on this topic,
I agree I can update the logic to only check for
short data if Direction is not EfiUsbNoData. That
should help reduce questions in future reviews of
this function. I will also add more comments.
Thanks for the feedback.
Mike
> -----Original Message-----
> From: Zeng, Star
> Sent: Wednesday, November 15, 2017 6:26 PM
> To: Kinney, Michael D <[email protected]>;
> [email protected]
> Cc: Dong, Eric <[email protected]>; Zeng, Star
> <[email protected]>
> Subject: RE: [Patch V2 1/2] MdeModulePkg/UsbBusDxe: Add
> UsbControlTransfer() error check
>
> Mike,
>
> Yes, the DataLength could be read. And Data/DataLength
> is optional when Direction is EfiUsbNoData per my
> understanding.
>
> IN OUT VOID *Data, OPTIONAL
> IN UINTN DataLength, OPTIONAL
>
>
> Thanks,
> Star
> -----Original Message-----
> From: Kinney, Michael D
> Sent: Thursday, November 16, 2017 12:44 AM
> To: Zeng, Star <[email protected]>; edk2-
> [email protected]; Kinney, Michael D
> <[email protected]>
> Cc: Dong, Eric <[email protected]>
> Subject: RE: [Patch V2 1/2] MdeModulePkg/UsbBusDxe: Add
> UsbControlTransfer() error check
>
> Star,
>
> I have read that section, and I do not see anything
> that says the DataLength parameter can not be read.
>
> Mike
>
> > -----Original Message-----
> > From: Zeng, Star
> > Sent: Tuesday, November 14, 2017 8:23 PM
> > To: Kinney, Michael D <[email protected]>;
> > [email protected]
> > Cc: Dong, Eric <[email protected]>; Zeng, Star
> <[email protected]>
> > Subject: RE: [Patch V2 1/2] MdeModulePkg/UsbBusDxe:
> Add
> > UsbControlTransfer() error check
> >
> > Mike,
> >
> > UEFI spec, EFI_USB_IO_PROTOCOL.UsbControlTransfer(),
> in the
> > description.
> >
> > Thanks,
> > Star
> > -----Original Message-----
> > From: Kinney, Michael D
> > Sent: Wednesday, November 15, 2017 12:00 PM
> > To: Zeng, Star <[email protected]>; edk2-
> [email protected];
> > Kinney, Michael D <[email protected]>
> > Cc: Dong, Eric <[email protected]>
> > Subject: RE: [Patch V2 1/2] MdeModulePkg/UsbBusDxe:
> Add
> > UsbControlTransfer() error check
> >
> > Star,
> >
> > I am curious. Which spec statement are you referring
> to?
> >
> > Mike
> >
> > > -----Original Message-----
> > > From: Zeng, Star
> > > Sent: Tuesday, November 14, 2017 6:59 PM
> > > To: Kinney, Michael D <[email protected]>;
> > > [email protected]
> > > Cc: Dong, Eric <[email protected]>; Zeng, Star
> > <[email protected]>
> > > Subject: RE: [Patch V2 1/2] MdeModulePkg/UsbBusDxe:
> > Add
> > > UsbControlTransfer() error check
> > >
> > > Mike,
> > >
> > > I do not insist on the check that the Direction is
> > not EfiUsbNoData,
> > > and I know the functionality should have no
> > improvement with the
> > > check.
> > > So, you can have my Reviewed-by: Star Zeng
> > <[email protected]>.
> > >
> > > I raised the question just for consideration from
> > literally, as
> > > according to the spec, the code could not touch
> > DataLength at all when
> > > Direction is EfiUsbNoData.
> > >
> > > You can decide to have / have not the check when
> > pushing. :)
> > >
> > >
> > > Thanks,
> > > Star
> > > -----Original Message-----
> > > From: Kinney, Michael D
> > > Sent: Wednesday, November 15, 2017 10:46 AM
> > > To: Zeng, Star <[email protected]>; edk2-
> > [email protected];
> > > Kinney, Michael D <[email protected]>
> > > Cc: Dong, Eric <[email protected]>
> > > Subject: RE: [Patch V2 1/2] MdeModulePkg/UsbBusDxe:
> > Add
> > > UsbControlTransfer() error check
> > >
> > > Star,
> > >
> > > For that case both DataLength and
> RequestedDataLength
> > will be 0 and
> > > the new path will not be taken.
> > >
> > > Are you concerned that the USB HC Protocol could
> > return a non zero
> > > DataLength for the EfiUsbNoData case? Even if it
> > does, the new path
> > > can never be taken because 0 is less than all UINTN
> > values.
> > >
> > > Mike
> > >
> > > > -----Original Message-----
> > > > From: Zeng, Star
> > > > Sent: Tuesday, November 14, 2017 6:40 PM
> > > > To: Kinney, Michael D
> <[email protected]>;
> > > > [email protected]
> > > > Cc: Dong, Eric <[email protected]>; Zeng, Star
> > > <[email protected]>
> > > > Subject: RE: [Patch V2 1/2]
> MdeModulePkg/UsbBusDxe:
> > > Add
> > > > UsbControlTransfer() error check
> > > >
> > > > Mike,
> > > >
> > > > Do you think it is better or not to also check
> the
> > > Direction is not
> > > > EfiUsbNoData?
> > > >
> > > > UEFI spec,
> > EFI_USB_IO_PROTOCOL.UsbControlTransfer():
> > > > If the Direction parameter is EfiUsbNoData, Data
> is
> > > NULL, and
> > > > DataLength is 0, then no data phase exists for
> the
> > > control transfer.
> > > >
> > > > Thanks,
> > > > Star
> > > > -----Original Message-----
> > > > From: Kinney, Michael D
> > > > Sent: Wednesday, November 15, 2017 9:03 AM
> > > > To: [email protected]
> > > > Cc: Zeng, Star <[email protected]>; Dong, Eric
> > > <[email protected]>
> > > > Subject: [Patch V2 1/2] MdeModulePkg/UsbBusDxe:
> Add
> > > > UsbControlTransfer() error check
> > > >
> > > >
> https://bugzilla.tianocore.org/show_bug.cgi?id=767
> > > >
> > > > The USB I/O Protocol function ControlTransfer()
> has
> > a
> > > DataLength
> > > > parameter that specifies the size of the Data
> > buffer.
> > > The UsbBusDxe
> > > > module implements the USB I/O Protocol using the
> > > services of the USB2
> > > > Host Controller Protocol. The DataLength
> parameter
> > > in the
> > > > USB2 Host Controller Protocol ControlTransfer()
> > > service is an IN OUT
> > > > parameter so the number of bytes actually
> > transferred
> > > is returned.
> > > > Since the USB I/O Protocol
> > > > ControlTransfer() service can not return the
> number
> > > of bytes actually
> > > > transferred, the only option if the number of
> bytes
> > > actually
> > > > transferred is less than the number of bytes
> > > requested is to return
> > > > EFI_DEVICE_ERROR.
> > > >
> > > > The change fixes an issue with a USB mass storage
> > > device that responds
> > > > with 0 bytes to the Get MAX LUN command.
> > > >
> > > > Cc: Star Zeng <[email protected]>
> > > > Cc: Eric Dong <[email protected]>
> > > > Contributed-under: TianoCore Contribution
> Agreement
> > > 1.1
> > > > Signed-off-by: Michael D Kinney
> > > > <[email protected]>
> > > > ---
> > > > MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c | 8
> > +++++++-
> > > > 1 file changed, 7 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git
> > a/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c
> > > > b/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c
> > > > index 78220222f6..b0ad7938e9 100644
> > > > --- a/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c
> > > > +++ b/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c
> > > > @@ -2,7 +2,7 @@
> > > >
> > > > Usb Bus Driver Binding and Bus IO Protocol.
> > > >
> > > > -Copyright (c) 2004 - 2016, Intel Corporation.
> All
> > > rights
> > > > reserved.<BR>
> > > > +Copyright (c) 2004 - 2017, Intel Corporation.
> All
> > > > rights reserved.<BR>
> > > > This program and the accompanying materials are
> > > licensed and made
> > > > available under the terms and conditions of the
> BSD
> > > License which
> > > > accompanies this distribution. The full text of
> > the
> > > license may be
> > > > found at @@ -76,6 +76,7 @@ UsbIoControlTransfer (
> > > > USB_ENDPOINT_DESC *EpDesc;
> > > > EFI_TPL OldTpl;
> > > > EFI_STATUS Status;
> > > > + UINTN RequestedDataLength;
> > > >
> > > > if (UsbStatus == NULL) {
> > > > return EFI_INVALID_PARAMETER; @@ -86,6 +87,7
> @@
> > > > UsbIoControlTransfer (
> > > > UsbIf = USB_INTERFACE_FROM_USBIO (This);
> > > > Dev = UsbIf->Device;
> > > >
> > > > + RequestedDataLength = DataLength;
> > > > Status = UsbHcControlTransfer (
> > > > Dev->Bus,
> > > > Dev->Address,
> > > > @@ -99,6 +101,10 @@ UsbIoControlTransfer (
> > > > &Dev->Translator,
> > > > UsbStatus
> > > > );
> > > > + if (!EFI_ERROR (Status) && DataLength <
> > > > RequestedDataLength) {
> > > > + Status = EFI_DEVICE_ERROR;
> > > > + goto ON_EXIT;
> > > > + }
> > > >
> > > > if (EFI_ERROR (Status) || (*UsbStatus !=
> > > > EFI_USB_NOERROR)) {
> > > > //
> > > > --
> > > > 2.14.2.windows.3
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