From: Mathias Nyman <mathias.nyman@linux.intel.com>
Date: Thu, 11 Sep 2014 10:55:48 +0000 (+0300)
Subject: xhci: Fix null pointer dereference if xhci initialization fails
X-Git-Tag: firefly_0821_release~3679^2~1495
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=7aeede98bdbcbca2956822ce7a871e875663c6b6;p=firefly-linux-kernel-4.4.55.git

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@gmx.de>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index d007f0920126..677f032482f7 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1795,7 +1795,7 @@ 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;