--- /dev/null
+From ec963b412a54aac8e527708ecad06a6988a86fb4 Mon Sep 17 00:00:00 2001
+From: Johan Hovold <johan@kernel.org>
+Date: Wed, 10 May 2017 18:18:26 +0200
+Subject: USB: usbip: fix nonconforming hub descriptor
+
+From: Johan Hovold <johan@kernel.org>
+
+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@users.sourceforge.net>
+Cc: Valentina Manea <valentina.manea.m@gmail.com>
+Signed-off-by: Johan Hovold <johan@kernel.org>
+Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
+[ johan: backport to v4.4, which uses VHCI_NPORTS ]
+Signed-off-by: Johan Hovold <johan@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ 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,