From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f194.google.com ([209.85.128.194]:36536 "EHLO mail-wr0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753156AbdEJMxI (ORCPT ); Wed, 10 May 2017 08:53:08 -0400 From: Johan Hovold To: Greg Kroah-Hartman Cc: Alan Stern , Felipe Balbi , Mathias Nyman , linux-usb@vger.kernel.org, Johan Hovold , stable , John Youn Subject: [PATCH 3/6] USB: hub: fix SS hub-descriptor handling Date: Wed, 10 May 2017 14:50:53 +0200 Message-Id: <20170510125056.29155-4-johan@kernel.org> In-Reply-To: <20170510125056.29155-1-johan@kernel.org> References: <20170510125056.29155-1-johan@kernel.org> Sender: stable-owner@vger.kernel.org List-ID: A SuperSpeed hub descriptor does not have any variable-length fields so bail out when reading a short descriptor. This avoids parsing and leaking two bytes of uninitialised slab data through sysfs removable-attributes. Fixes: dbe79bbe9dcb ("USB 3.0 Hub Changes") Cc: stable # 2.6.39 Cc: John Youn Signed-off-by: Johan Hovold --- drivers/usb/core/hub.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 9dca59ef18b3..3ff1e9f89f2d 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -380,8 +380,12 @@ static int get_hub_descriptor(struct usb_device *hdev, void *data) USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB, dtype << 8, 0, data, size, USB_CTRL_GET_TIMEOUT); - if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2)) + if (hub_is_superspeed(hdev)) { + if (ret == size) + return ret; + } else if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2)) { return ret; + } } return -EINVAL; } @@ -1321,7 +1325,7 @@ static int hub_configure(struct usb_hub *hub, /* Request the entire hub descriptor. * hub->descriptor can handle USB_MAXCHILDREN ports, - * but the hub can/will return fewer bytes here. + * but a (non-SS) hub can/will return fewer bytes here. */ ret = get_hub_descriptor(hdev, hub->descriptor); if (ret < 0) { -- 2.13.0