[PATCH 4.4 013/163] usb: xhci: fix wild pointers in xhci_mem_cleanup

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>

commit 71504062a7c34838c3fccd92c447f399d3cb5797 upstream.

This patch fixes some wild pointers produced by xhci_mem_cleanup.
These wild pointers will cause system crash if xhci_mem_cleanup()
is called twice.

Reported-and-tested-by: Pengcheng Li <lpc.li@xxxxxxxxxxxxx>
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/host/xhci-mem.c |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1875,6 +1875,12 @@ no_bw:
 	kfree(xhci->rh_bw);
 	kfree(xhci->ext_caps);
 
+	xhci->usb2_ports = NULL;
+	xhci->usb3_ports = NULL;
+	xhci->port_array = NULL;
+	xhci->rh_bw = NULL;
+	xhci->ext_caps = NULL;
+
 	xhci->page_size = 0;
 	xhci->page_shift = 0;
 	xhci->bus_state[0].bus_suspended = 0;