USB: don't choose configs with no interfaces

This patch (as1372) fixes a bug in the routine that chooses the
default configuration to install when a new USB device is detected.
The algorithm is supposed to look for a config whose first interface
is for a non-vendor-specific class.  But the way it's currently
written, it will also accept a config with no interfaces at all, which
is not very useful.  (Believe it or not, such things do exist.)

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Andrew Victor <avictor.za@gmail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Stern 2010-04-20 10:40:59 -04:00 committed by Greg Kroah-Hartman
parent c3baa19b0a
commit 62f9cfa3ec

View File

@ -120,7 +120,7 @@ int usb_choose_configuration(struct usb_device *udev)
* than a vendor-specific driver. */
else if (udev->descriptor.bDeviceClass !=
USB_CLASS_VENDOR_SPEC &&
(!desc || desc->bInterfaceClass !=
(desc && desc->bInterfaceClass !=
USB_CLASS_VENDOR_SPEC)) {
best = c;
break;