[3.13.y.z extended stable] Patch "xhci: Fix null pointer dereference if xhci initialization fails" has been added to staging queue

Kamal Mostafa kamal at canonical.com
Wed Oct 8 22:14:12 UTC 2014

This is a note to let you know that I have just added a patch titled

    xhci: Fix null pointer dereference if xhci initialization fails

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:


This patch is scheduled to be released in version

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see



>From caaeafd7651a3bde47e751cc2343d2f624a36458 Mon Sep 17 00:00:00 2001
From: Mathias Nyman <mathias.nyman at linux.intel.com>
Date: Thu, 11 Sep 2014 13:55:48 +0300
Subject: xhci: Fix null pointer dereference if xhci initialization fails

commit c207e7c50f31113c24a9f536fcab1e8a256985d7 upstream.

If xhci initialization fails before the roothub bandwidth
domains (xhci->rh_bw[i]) are allocated it will oops when
trying to access rh_bw members in xhci_mem_cleanup().

Reported-by: Manuel Reimer <manuel.reimer at gmx.de>
Signed-off-by: Mathias Nyman <mathias.nyman at linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
 drivers/usb/host/xhci-mem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 4483e6a..837c333 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1723,7 +1723,7 @@ void xhci_mem_cleanup(struct xhci_hcd *xhci)

 	num_ports = HCS_MAX_PORTS(xhci->hcs_params1);
-	for (i = 0; i < num_ports; i++) {
+	for (i = 0; i < num_ports && xhci->rh_bw; i++) {
 		struct xhci_interval_bw_table *bwt = &xhci->rh_bw[i].bw_table;
 		for (j = 0; j < XHCI_MAX_INTERVAL; j++) {
 			struct list_head *ep = &bwt->interval_bw[j].endpoints;

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