On 17/04/15(Fri) 16:47, Dimitris Papastamos wrote: > Hi, > > This patch adds an option to usbdevs(8) to disable USB bus probing > at runtime. The operation is restricted to the root user.
It would be nice to show if probing is on or off, for example # usbdevs -p bus probing: on # usbdevs -p off But other people might have better suggestions. > I am not sure if this approach is sensible or even correct. Some > pointers would be much appreciated. Setting a variable per hub (and here roothub) is overkill, a global would be enough. > > This was started as part of a reply by mpi on tech@ > > http://marc.info/?l=openbsd-tech&m=142917883126679&w=2 > > I guess the reasoning behind this is to add some protection against > things like badusb? It can have multiple usages :) How did you try it? What happen if you plug a hub with multiple devices, turn bus probing off then detach the hub? What happen if you plug a device like a phone that use the power to charge its battery after turning probing off. If I read your diff correctly you still allow the device to be charged which is fine. Did you try that? I think it's worth a documentation note. > if (!dev->self_powered && dev->powersrc->parent != NULL && > !dev->powersrc->parent->self_powered) { > @@ -494,6 +495,9 @@ uhub_explore(struct usbd_device *dev) > */ > if (speed > sc->sc_hub->speed) > speed = sc->sc_hub->speed; > + > + if (dev->hub->noprobe) > + return (0); I believe you can move that before the "Figure out device speed".
