From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752452AbdIIW4e (ORCPT ); Sat, 9 Sep 2017 18:56:34 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:41298 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751748AbdIIWYk (ORCPT ); Sat, 9 Sep 2017 18:24:40 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Greg Kroah-Hartman" , "Johan Hovold" , "John Youn" , "Alan Stern" Date: Sat, 09 Sep 2017 22:47:39 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 019/106] USB: hub: fix SS hub-descriptor handling In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.93-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 2c25a2c818023df64463aac3288a9f969491e507 upstream. 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: John Youn Acked-by: Alan Stern Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/usb/core/hub.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -195,8 +195,12 @@ static int get_hub_descriptor(struct usb 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; } @@ -1121,7 +1125,7 @@ static int hub_configure(struct usb_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) {