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=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,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 18E10C004D2 for ; Tue, 2 Oct 2018 13:29:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D27E62089C for ; Tue, 2 Oct 2018 13:29:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D27E62089C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729953AbeJBUMv (ORCPT ); Tue, 2 Oct 2018 16:12:51 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:33126 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726758AbeJBUMu (ORCPT ); Tue, 2 Oct 2018 16:12:50 -0400 Received: from localhost (24-104-73-23-ip-static.hfc.comcastbusiness.net [24.104.73.23]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 40F42266; Tue, 2 Oct 2018 13:29:28 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alan Stern , syzbot+19c3aaef85a89d451eac@syzkaller.appspotmail.com Subject: [PATCH 4.18 149/228] USB: handle NULL config in usb_find_alt_setting() Date: Tue, 2 Oct 2018 06:24:06 -0700 Message-Id: <20181002132509.193759612@linuxfoundation.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20181002132459.032960735@linuxfoundation.org> References: <20181002132459.032960735@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review 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 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alan Stern commit c9a4cb204e9eb7fa7dfbe3f7d3a674fa530aa193 upstream. usb_find_alt_setting() takes a pointer to a struct usb_host_config as an argument; it searches for an interface with specified interface and alternate setting numbers in that config. However, it crashes if the usb_host_config pointer argument is NULL. Since this is a general-purpose routine, available for use in many places, we want to to be more robust. This patch makes it return NULL whenever the config argument is NULL. Signed-off-by: Alan Stern Reported-by: syzbot+19c3aaef85a89d451eac@syzkaller.appspotmail.com CC: Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/usb.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -228,6 +228,8 @@ struct usb_host_interface *usb_find_alt_ struct usb_interface_cache *intf_cache = NULL; int i; + if (!config) + return NULL; for (i = 0; i < config->desc.bNumInterfaces; i++) { if (config->intf_cache[i]->altsetting[0].desc.bInterfaceNumber == iface_num) {