From patchwork Fri Mar 5 12:18:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mauro Carvalho Chehab X-Patchwork-Id: 394489 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=-14.0 required=3.0 tests=BAYES_00, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED 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 69FB9C433DB for ; Fri, 5 Mar 2021 12:22:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 196B864FED for ; Fri, 5 Mar 2021 12:22:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229582AbhCEMV3 (ORCPT ); Fri, 5 Mar 2021 07:21:29 -0500 Received: from www.linuxtv.org ([130.149.80.248]:34348 "EHLO www.linuxtv.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229794AbhCEMVP (ORCPT ); Fri, 5 Mar 2021 07:21:15 -0500 Received: from mchehab by www.linuxtv.org with local (Exim 4.92) (envelope-from ) id 1lI9SC-002Sdg-Vh; Fri, 05 Mar 2021 12:21:12 +0000 From: Mauro Carvalho Chehab Date: Fri, 05 Mar 2021 12:18:40 +0000 Subject: [git:media_tree/master] media: dvb-usb: Fix use-after-free access To: linuxtv-commits@linuxtv.org Cc: Takashi Iwai , Robert Foss , Sean Young , Stefan Seyfried , stable@vger.kernel.org Mail-followup-to: linux-media@vger.kernel.org Forward-to: linux-media@vger.kernel.org Reply-to: linux-media@vger.kernel.org Message-Id: Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is an automatic generated email to let you know that the following patch were queued: Subject: media: dvb-usb: Fix use-after-free access Author: Takashi Iwai Date: Mon Feb 1 09:32:47 2021 +0100 dvb_usb_device_init() copies the properties to the own data, so that the callers can release the original properties later (as done in the commit 299c7007e936 ("media: dw2102: Fix memleak on sequence of probes")). However, it also stores dev->desc pointer that is a reference to the original properties data. Since dev->desc is referred later, it may result in use-after-free, in the worst case, leading to a kernel Oops as reported. This patch addresses the problem by allocating and copying the properties at first, then get the desc from the copied properties. Reported-and-tested-by: Stefan Seyfried BugLink: http://bugzilla.opensuse.org/show_bug.cgi?id=1181104 Reviewed-by: Robert Foss Cc: Signed-off-by: Takashi Iwai Signed-off-by: Sean Young Signed-off-by: Mauro Carvalho Chehab drivers/media/usb/dvb-usb/dvb-usb-init.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/media/usb/dvb-usb/dvb-usb-init.c b/drivers/media/usb/dvb-usb/dvb-usb-init.c index c78158d12540..6c9e3290af56 100644 --- a/drivers/media/usb/dvb-usb/dvb-usb-init.c +++ b/drivers/media/usb/dvb-usb/dvb-usb-init.c @@ -264,27 +264,30 @@ int dvb_usb_device_init(struct usb_interface *intf, if (du != NULL) *du = NULL; - if ((desc = dvb_usb_find_device(udev, props, &cold)) == NULL) { + d = kzalloc(sizeof(*d), GFP_KERNEL); + if (!d) { + err("no memory for 'struct dvb_usb_device'"); + return -ENOMEM; + } + + memcpy(&d->props, props, sizeof(struct dvb_usb_device_properties)); + + desc = dvb_usb_find_device(udev, &d->props, &cold); + if (!desc) { deb_err("something went very wrong, device was not found in current device list - let's see what comes next.\n"); - return -ENODEV; + ret = -ENODEV; + goto error; } if (cold) { info("found a '%s' in cold state, will try to load a firmware", desc->name); ret = dvb_usb_download_firmware(udev, props); if (!props->no_reconnect || ret != 0) - return ret; + goto error; } info("found a '%s' in warm state.", desc->name); - d = kzalloc(sizeof(struct dvb_usb_device), GFP_KERNEL); - if (d == NULL) { - err("no memory for 'struct dvb_usb_device'"); - return -ENOMEM; - } - d->udev = udev; - memcpy(&d->props, props, sizeof(struct dvb_usb_device_properties)); d->desc = desc; d->owner = owner;