From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:48514 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031481AbdEWU3g (ORCPT ); Tue, 23 May 2017 16:29:36 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johan Hovold , Alan Stern Subject: [PATCH 4.9 095/164] USB: hub: fix non-SS hub-descriptor handling Date: Tue, 23 May 2017 22:08:32 +0200 Message-Id: <20170523200911.245821962@linuxfoundation.org> In-Reply-To: <20170523200907.297534241@linuxfoundation.org> References: <20170523200907.297534241@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit bec444cd1c94c48df409a35ad4e5b143c245c3f7 upstream. Add missing sanity check on the non-SuperSpeed hub-descriptor length in order to avoid parsing and leaking two bytes of uninitialised slab data through sysfs removable-attributes (or a compound-device debug statement). Note that we only make sure that the DeviceRemovable field is always present (and specifically ignore the unused PortPwrCtrlMask field) in order to continue support any hubs with non-compliant descriptors. As a further safeguard, the descriptor buffer is also cleared. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Johan Hovold Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -360,7 +360,8 @@ static void usb_set_lpm_parameters(struc } /* USB 2.0 spec Section 11.24.4.5 */ -static int get_hub_descriptor(struct usb_device *hdev, void *data) +static int get_hub_descriptor(struct usb_device *hdev, + struct usb_hub_descriptor *desc) { int i, ret, size; unsigned dtype; @@ -376,12 +377,16 @@ static int get_hub_descriptor(struct usb for (i = 0; i < 3; i++) { ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0), USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB, - dtype << 8, 0, data, size, + dtype << 8, 0, desc, size, USB_CTRL_GET_TIMEOUT); if (hub_is_superspeed(hdev)) { if (ret == size) return ret; - } else if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2)) { + } else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) { + /* Make sure we have the DeviceRemovable field. */ + size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1; + if (ret < size) + return -EMSGSIZE; return ret; } } @@ -1315,7 +1320,7 @@ static int hub_configure(struct usb_hub } mutex_init(&hub->status_mutex); - hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL); + hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL); if (!hub->descriptor) { ret = -ENOMEM; goto fail;