From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A1BB5C2BCA1 for ; Fri, 7 Jun 2019 15:41:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6D594214AE for ; Fri, 7 Jun 2019 15:41:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559922083; bh=TwpQH5IEGVm1BfQanqjx4j2oQNl5Cm9iB/CvJp+FJHQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zWl69rj3Yu+P52OaoZ45lEaT2XAdsv37mls0XMrPaL6MlWCffgPoHFVhNK6BS/32J WJGJGIiWSd3yjgq4dT74w9OdzxoUyaQR042GWqRwPAyd/m68HJQrhD8gWmicT38TLy j0FSMkDhY/3rPMxnz3iRvXo1iHuO1MELGlEuphsk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730296AbfFGPlW (ORCPT ); Fri, 7 Jun 2019 11:41:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:51148 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729325AbfFGPlV (ORCPT ); Fri, 7 Jun 2019 11:41:21 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E0C0B212F5; Fri, 7 Jun 2019 15:41:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559922080; bh=TwpQH5IEGVm1BfQanqjx4j2oQNl5Cm9iB/CvJp+FJHQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iA099m467p3siyG/5phXQWhdHQN4pObatnXxiOE3v5y4tKhpBs4k1EkKZmvU/8tRn 0xp0k5tVVtf4tVj8Oh3QSYs441B8diVlWm4bFON8fR7WfBSY23M4awoZb5qKjQE3U7 rso5ZDJ8hgYjjV7fhC96Z4ejO+7Obuj9Grh20pzU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alan Stern , syzbot+71f1e64501a309fcc012@syzkaller.appspotmail.com Subject: [PATCH 4.14 29/69] USB: Fix slab-out-of-bounds write in usb_get_bos_descriptor Date: Fri, 7 Jun 2019 17:39:10 +0200 Message-Id: <20190607153851.981453928@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190607153848.271562617@linuxfoundation.org> References: <20190607153848.271562617@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alan Stern commit a03ff54460817c76105f81f3aa8ef655759ccc9a upstream. The syzkaller USB fuzzer found a slab-out-of-bounds write bug in the USB core, caused by a failure to check the actual size of a BOS descriptor. This patch adds a check to make sure the descriptor is at least as large as it is supposed to be, so that the code doesn't inadvertently access memory beyond the end of the allocated region when assigning to dev->bos->desc->bNumDeviceCaps later on. Signed-off-by: Alan Stern Reported-and-tested-by: syzbot+71f1e64501a309fcc012@syzkaller.appspotmail.com CC: Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/config.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/usb/core/config.c +++ b/drivers/usb/core/config.c @@ -936,8 +936,8 @@ int usb_get_bos_descriptor(struct usb_de /* Get BOS descriptor */ ret = usb_get_descriptor(dev, USB_DT_BOS, 0, bos, USB_DT_BOS_SIZE); - if (ret < USB_DT_BOS_SIZE) { - dev_err(ddev, "unable to get BOS descriptor\n"); + if (ret < USB_DT_BOS_SIZE || bos->bLength < USB_DT_BOS_SIZE) { + dev_err(ddev, "unable to get BOS descriptor or descriptor too short\n"); if (ret >= 0) ret = -ENOMSG; kfree(bos);