4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold <johan@xxxxxxxxxx> commit ec963b412a54aac8e527708ecad06a6988a86fb4 upstream. Fix up the root-hub descriptor to accommodate the variable-length DeviceRemovable and PortPwrCtrlMask fields, while marking all ports as removable (and leaving the reserved bit zero unset). Also add a build-time constraint on VHCI_HC_PORTS which must never be greater than USB_MAXCHILDREN (but this was only enforced through a KConfig constant). This specifically fixes the descriptor layout whenever VHCI_HC_PORTS is greater than seven (default is 8). Fixes: 04679b3489e0 ("Staging: USB/IP: add client driver") Cc: Takahiro Hirofuchi <hirofuchi@xxxxxxxxxxxxxxxxxxxxx> Cc: Valentina Manea <valentina.manea.m@xxxxxxxxx> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> Acked-by: Shuah Khan <shuahkh@xxxxxxxxxxxxxxx> [ johan: backport to v4.4, which uses VHCI_NPORTS ] Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/usbip/vhci_hcd.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) --- a/drivers/usb/usbip/vhci_hcd.c +++ b/drivers/usb/usbip/vhci_hcd.c @@ -215,14 +215,19 @@ done: static inline void hub_descriptor(struct usb_hub_descriptor *desc) { + int width; + memset(desc, 0, sizeof(*desc)); desc->bDescriptorType = USB_DT_HUB; - desc->bDescLength = 9; desc->wHubCharacteristics = cpu_to_le16( HUB_CHAR_INDV_PORT_LPSM | HUB_CHAR_COMMON_OCPM); + desc->bNbrPorts = VHCI_NPORTS; - desc->u.hs.DeviceRemovable[0] = 0xff; - desc->u.hs.DeviceRemovable[1] = 0xff; + BUILD_BUG_ON(VHCI_NPORTS > USB_MAXCHILDREN); + width = desc->bNbrPorts / 8 + 1; + desc->bDescLength = USB_DT_HUB_NONVAR_SIZE + 2 * width; + memset(&desc->u.hs.DeviceRemovable[0], 0, width); + memset(&desc->u.hs.DeviceRemovable[width], 0xff, width); } static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,