Re: [PATCH v3 2/2] usb: host: max3421: Reject hub port requests for non-existent ports

[Seungjin Bae]

2026년 5월 18일 (월) 오후 5:54, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>님이 작성:
>
> On Sun, May 17, 2026 at 03:03:08PM -0400, pip-izony wrote:
> > From: Seungjin Bae <eeodqql09@xxxxxxxxx>
> >
> > The `max3421_hub_control()` function handles USB hub class requests
> > to the virtual root hub. The `GetPortStatus` case correctly rejects
> > requests with `index != 1`, since the virtual root hub has only a
> > single port. However, the `ClearPortFeature` and `SetPortFeature`
> > cases lack the same check.
> >
> > Fix this by extending the `index != 1` rejection to both cases,
> > matching the existing behavior of `GetPortStatus`.
> >
> > Fixes: 2d53139f3162 ("Add support for using a MAX3421E chip as a host driver.")
> > Suggested-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Seungjin Bae <eeodqql09@xxxxxxxxx>
> > ---
>
> Reviewed-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
>
> Heh, this made me go back and look at dummy-hcd.c.  It's missing the
> same check in the same places!
>
> Would you like to submit a patch to fix that driver as well?  If not,
> I'll take care of it.
Thanks for pointing this out.
I'll send a separate patch for that shortly.

Seungjin Bae
>
> Alan Stern
>
> >  v3: New patch in v3, suggested by Alan Stern.
> >
> >  drivers/usb/host/max3421-hcd.c | 4 ++++
> >  1 file changed, 4 insertions(+)
> >
> > diff --git a/drivers/usb/host/max3421-hcd.c b/drivers/usb/host/max3421-hcd.c
> > index 3d6b351dcb1a..73e76d0e6973 100644
> > --- a/drivers/usb/host/max3421-hcd.c
> > +++ b/drivers/usb/host/max3421-hcd.c
> > @@ -1685,6 +1685,8 @@ max3421_hub_control(struct usb_hcd *hcd, u16 type_req, u16 value, u16 index,
> >       case ClearHubFeature:
> >               break;
> >       case ClearPortFeature:
> > +             if (index != 1)
> > +                     goto error;
> >               switch (value) {
> >               case USB_PORT_FEAT_SUSPEND:
> >                       break;
> > @@ -1728,6 +1730,8 @@ max3421_hub_control(struct usb_hcd *hcd, u16 type_req, u16 value, u16 index,
> >               break;
> >
> >       case SetPortFeature:
> > +             if (index != 1)
> > +                     goto error;
> >               switch (value) {
> >               case USB_PORT_FEAT_LINK_STATE:
> >               case USB_PORT_FEAT_U1_TIMEOUT:
> > --
> > 2.43.0
> >