From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754997AbdLGNPP (ORCPT ); Thu, 7 Dec 2017 08:15:15 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:34836 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755758AbdLGNNZ (ORCPT ); Thu, 7 Dec 2017 08:13:25 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Masakazu Mokuno Subject: [PATCH 4.14 73/75] USB: core: Add type-specific length check of BOS descriptors Date: Thu, 7 Dec 2017 14:08:35 +0100 Message-Id: <20171207130821.764945123@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171207130818.742746317@linuxfoundation.org> References: <20171207130818.742746317@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Masakazu Mokuno commit 81cf4a45360f70528f1f64ba018d61cb5767249a upstream. As most of BOS descriptors are longer in length than their header 'struct usb_dev_cap_header', comparing solely with it is not sufficient to avoid out-of-bounds access to BOS descriptors. This patch adds descriptor type specific length check in usb_get_bos_descriptor() to fix the issue. Signed-off-by: Masakazu Mokuno Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/config.c | 28 ++++++++++++++++++++++++---- include/uapi/linux/usb/ch9.h | 3 +++ 2 files changed, 27 insertions(+), 4 deletions(-) --- a/drivers/usb/core/config.c +++ b/drivers/usb/core/config.c @@ -905,14 +905,25 @@ void usb_release_bos_descriptor(struct u } } +static const __u8 bos_desc_len[256] = { + [USB_CAP_TYPE_WIRELESS_USB] = USB_DT_USB_WIRELESS_CAP_SIZE, + [USB_CAP_TYPE_EXT] = USB_DT_USB_EXT_CAP_SIZE, + [USB_SS_CAP_TYPE] = USB_DT_USB_SS_CAP_SIZE, + [USB_SSP_CAP_TYPE] = USB_DT_USB_SSP_CAP_SIZE(1), + [CONTAINER_ID_TYPE] = USB_DT_USB_SS_CONTN_ID_SIZE, + [USB_PTM_CAP_TYPE] = USB_DT_USB_PTM_ID_SIZE, +}; + /* Get BOS descriptor set */ int usb_get_bos_descriptor(struct usb_device *dev) { struct device *ddev = &dev->dev; struct usb_bos_descriptor *bos; struct usb_dev_cap_header *cap; + struct usb_ssp_cap_descriptor *ssp_cap; unsigned char *buffer; - int length, total_len, num, i; + int length, total_len, num, i, ssac; + __u8 cap_type; int ret; bos = kzalloc(sizeof(struct usb_bos_descriptor), GFP_KERNEL); @@ -965,7 +976,13 @@ int usb_get_bos_descriptor(struct usb_de dev->bos->desc->bNumDeviceCaps = i; break; } + cap_type = cap->bDevCapabilityType; length = cap->bLength; + if (bos_desc_len[cap_type] && length < bos_desc_len[cap_type]) { + dev->bos->desc->bNumDeviceCaps = i; + break; + } + total_len -= length; if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) { @@ -973,7 +990,7 @@ int usb_get_bos_descriptor(struct usb_de continue; } - switch (cap->bDevCapabilityType) { + switch (cap_type) { case USB_CAP_TYPE_WIRELESS_USB: /* Wireless USB cap descriptor is handled by wusb */ break; @@ -986,8 +1003,11 @@ int usb_get_bos_descriptor(struct usb_de (struct usb_ss_cap_descriptor *)buffer; break; case USB_SSP_CAP_TYPE: - dev->bos->ssp_cap = - (struct usb_ssp_cap_descriptor *)buffer; + ssp_cap = (struct usb_ssp_cap_descriptor *)buffer; + ssac = (le32_to_cpu(ssp_cap->bmAttributes) & + USB_SSP_SUBLINK_SPEED_ATTRIBS) + 1; + if (length >= USB_DT_USB_SSP_CAP_SIZE(ssac)) + dev->bos->ssp_cap = ssp_cap; break; case CONTAINER_ID_TYPE: dev->bos->ss_id = --- a/include/uapi/linux/usb/ch9.h +++ b/include/uapi/linux/usb/ch9.h @@ -876,6 +876,8 @@ struct usb_wireless_cap_descriptor { /* __u8 bReserved; } __attribute__((packed)); +#define USB_DT_USB_WIRELESS_CAP_SIZE 11 + /* USB 2.0 Extension descriptor */ #define USB_CAP_TYPE_EXT 2 @@ -1068,6 +1070,7 @@ struct usb_ptm_cap_descriptor { __u8 bDevCapabilityType; } __attribute__((packed)); +#define USB_DT_USB_PTM_ID_SIZE 3 /* * The size of the descriptor for the Sublink Speed Attribute Count * (SSAC) specified in bmAttributes[4:0].