From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:36828 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932467AbcHHTVh (ORCPT ); Mon, 8 Aug 2016 15:21:37 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, James Patrick-Evans , Kees Cook , Linus Torvalds Subject: [PATCH 4.6 83/96] media: fix airspy usb probe error path Date: Mon, 8 Aug 2016 21:11:46 +0200 Message-Id: <20160808180247.538033057@linuxfoundation.org> In-Reply-To: <20160808180243.898163389@linuxfoundation.org> References: <20160808180243.898163389@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: James Patrick-Evans commit aa93d1fee85c890a34f2510a310e55ee76a27848 upstream. Fix a memory leak on probe error of the airspy usb device driver. The problem is triggered when more than 64 usb devices register with v4l2 of type VFL_TYPE_SDR or VFL_TYPE_SUBDEV. The memory leak is caused by the probe function of the airspy driver mishandeling errors and not freeing the corresponding control structures when an error occours registering the device to v4l2 core. A badusb device can emulate 64 of these devices, and then through continual emulated connect/disconnect of the 65th device, cause the kernel to run out of RAM and crash the kernel, thus causing a local DOS vulnerability. Fixes CVE-2016-5400 Signed-off-by: James Patrick-Evans Reviewed-by: Kees Cook Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/media/usb/airspy/airspy.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/drivers/media/usb/airspy/airspy.c +++ b/drivers/media/usb/airspy/airspy.c @@ -1072,7 +1072,7 @@ static int airspy_probe(struct usb_inter if (ret) { dev_err(s->dev, "Failed to register as video device (%d)\n", ret); - goto err_unregister_v4l2_dev; + goto err_free_controls; } dev_info(s->dev, "Registered as %s\n", video_device_node_name(&s->vdev)); @@ -1081,7 +1081,6 @@ static int airspy_probe(struct usb_inter err_free_controls: v4l2_ctrl_handler_free(&s->hdl); -err_unregister_v4l2_dev: v4l2_device_unregister(&s->v4l2_dev); err_free_mem: kfree(s);