usbfs: Always allow ctrl requests with USB_RECIP_ENDPOINT on the ctrl ep
authorHans de Goede <hdegoede@redhat.com>
Tue, 16 Apr 2013 09:08:33 +0000 (11:08 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 8 May 2013 02:51:53 +0000 (19:51 -0700)
commitcfec6f5f0ee497134df86b9e61314f5ff4c2fce2
treefc271b3db80cb594fa0ad07971a1d116b36fb759
parentebd414a67ba32d17a53dd506b01720e08c88e455
usbfs: Always allow ctrl requests with USB_RECIP_ENDPOINT on the ctrl ep

commit 1361bf4b9f9ef45e628a5b89e0fd9bedfdcb7104 upstream.

When usbfs receives a ctrl-request from userspace it calls check_ctrlrecip,
which for a request with USB_RECIP_ENDPOINT tries to map this to an interface
to see if this interface is claimed, except for ctrl-requests with a type of
USB_TYPE_VENDOR.

When trying to use this device: http://www.akaipro.com/eiepro
redirected to a Windows vm running on qemu on top of Linux.

The windows driver makes a ctrl-req with USB_TYPE_CLASS and
USB_RECIP_ENDPOINT with index 0, and the mapping of the endpoint (0) to
the interface fails since ep 0 is the ctrl endpoint and thus never is
part of an interface.

This patch fixes this ctrl-req failing by skipping the checkintf call for
USB_RECIP_ENDPOINT ctrl-reqs on the ctrl endpoint.

Reported-by: Dave Stikkolorum <d.r.stikkolorum@hhs.nl>
Tested-by: Dave Stikkolorum <d.r.stikkolorum@hhs.nl>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/core/devio.c