On Thu, 5 Dec 2013, Julius Werner wrote: > usb_deauthorize_device() tries to unset the configuration of a USB > device and then unconditionally blows away the configuration descriptors > with usb_destroy_configuration(). This is bad if the > usb_set_configuration() call failed before the configuration could be > correctly unset, since pointers like udev->actconfig can keep pointing > to the now invalid memory. We have encountered hard to reproduce crashes > from devices disconnected during suspend due to this, where khubd's > disconnect handling races with userspace tools that change authorization > on resume. > > It seems desirable that a USB device can always be marked as > unconfigured (reclaiming its bandwidth) in the kernel, regardless of > communication problems. This patch changes usb_set_configuration() to > ignore all failures in the case where no new configuration is being set. > > Signed-off-by: Julius Werner <jwerner@xxxxxxxxxxxx> Sorry for not getting back to this sooner. Ironically, it looks like this change isn't needed any more, thanks to Thomas Pugliese's patch: http://marc.info/?l=linux-usb&m=138661805209999&w=2 > --- a/drivers/usb/core/message.c > +++ b/drivers/usb/core/message.c > @@ -1774,7 +1775,7 @@ free_interfaces: > > /* Wake up the device so we can send it the Set-Config request */ > ret = usb_autoresume_device(dev); > - if (ret) > + if (ret && cp) > goto free_interfaces; That isn't quite right. If the autoresume fails then we have to skip the autosuspend call later on. Alan Stern -- 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
