xhci: xhci-mem: off by one in xhci_stream_id_to_ring()

BugLink: http://bugs.launchpad.net/bugs/1810554
commit 313db3d6488bb03b61b99de9dbca061f1fd838e1 upstream.

The > should be >= here so that we don't read one element beyond the end
of the ep->stream_info->stream_rings[] array.

Fixes: e9df17eb1408 ("USB: xhci: Correct assumptions about number of rings per endpoint.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index a8e9ca1ea5417344854ed2ad75e5a4b97ccc9f9d..37516897b14f4630fd65b7ede4e47a90adec4270 100644 (file)
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -591,7 +591,7 @@ struct xhci_ring *xhci_stream_id_to_ring(
        if (!ep->stream_info)
                return NULL;
 
-       if (stream_id > ep->stream_info->num_streams)
+       if (stream_id >= ep->stream_info->num_streams)
                return NULL;
        return ep->stream_info->stream_rings[stream_id];
 }