On Mon, May 30, 2011 at 09:09:15AM +0200, Carl-Daniel Hailfinger wrote: > USB treats all devices attached to a wireless USB host controller as > unauthorized by default and all devices attached to a wired USB host > controller as authorized by default. This default setting can be changed > manually per host controller by setting authorized_default in sysfs, but > only after the host controller is already active. > AFAICS there is a race between userspace setting authorized_default on > startup and the USB subsystem enumerating devices on the USB bus. If a > USB device is already plugged into a wired USB host controller on > startup, it may be marked as authorized (and thus accessed by the > kernel/userspace) before userspace has a chance to set > authorized_default on that host controller. This is undesirable in kiosk > situations where the user may have access to the USB ports of a machine > during startup. > > Add an "authorized_default" parameter to the usbcore module which has > three settings: > 0 is not authorized for all devices > 1 is authorized for all devices > 2 is authorized for all devices except wireless (default, old behaviour) Ick, who is going to remember that "2" is the "default" here? I understand this could be a problem, but could you think up a cleaner interface for this? Also, any new kernel/user API, like this one, needs to be documentented in Documentation/ABI/. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
