Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030364AbcDLSJn (ORCPT ); Tue, 12 Apr 2016 14:09:43 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:49090 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965625AbcDLSIY (ORCPT ); Tue, 12 Apr 2016 14:08:24 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Vladis Dronov , Dmitry Torokhov , Moritz Muehlenhoff , Luis Henriques Subject: [PATCH 3.16.y-ckt 10/17] Input: ati_remote2 - fix crashes on detecting device with invalid descriptor Date: Tue, 12 Apr 2016 19:07:57 +0100 Message-Id: <1460484484-22395-11-git-send-email-luis.henriques@canonical.com> In-Reply-To: <1460484484-22395-1-git-send-email-luis.henriques@canonical.com> References: <1460484484-22395-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3386 Lines: 109 3.16.7-ckt27 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Vladis Dronov commit 950336ba3e4a1ffd2ca60d29f6ef386dd2c7351d upstream. The ati_remote2 driver expects at least two interfaces with one endpoint each. If given malicious descriptor that specify one interface or no endpoints, it will crash in the probe function. Ensure there is at least two interfaces and one endpoint for each interface before using it. The full disclosure: http://seclists.org/bugtraq/2016/Mar/90 Reported-by: Ralf Spenneberg Signed-off-by: Vladis Dronov Signed-off-by: Dmitry Torokhov Cc: Moritz Muehlenhoff Signed-off-by: Luis Henriques --- drivers/input/misc/ati_remote2.c | 36 ++++++++++++++++++++++++++++++------ 1 file changed, 30 insertions(+), 6 deletions(-) diff --git a/drivers/input/misc/ati_remote2.c b/drivers/input/misc/ati_remote2.c index f63341f20b91..e8c6a4842e91 100644 --- a/drivers/input/misc/ati_remote2.c +++ b/drivers/input/misc/ati_remote2.c @@ -817,26 +817,49 @@ static int ati_remote2_probe(struct usb_interface *interface, const struct usb_d ar2->udev = udev; + /* Sanity check, first interface must have an endpoint */ + if (alt->desc.bNumEndpoints < 1 || !alt->endpoint) { + dev_err(&interface->dev, + "%s(): interface 0 must have an endpoint\n", __func__); + r = -ENODEV; + goto fail1; + } ar2->intf[0] = interface; ar2->ep[0] = &alt->endpoint[0].desc; + /* Sanity check, the device must have two interfaces */ ar2->intf[1] = usb_ifnum_to_if(udev, 1); + if ((udev->actconfig->desc.bNumInterfaces < 2) || !ar2->intf[1]) { + dev_err(&interface->dev, "%s(): need 2 interfaces, found %d\n", + __func__, udev->actconfig->desc.bNumInterfaces); + r = -ENODEV; + goto fail1; + } + r = usb_driver_claim_interface(&ati_remote2_driver, ar2->intf[1], ar2); if (r) goto fail1; + + /* Sanity check, second interface must have an endpoint */ alt = ar2->intf[1]->cur_altsetting; + if (alt->desc.bNumEndpoints < 1 || !alt->endpoint) { + dev_err(&interface->dev, + "%s(): interface 1 must have an endpoint\n", __func__); + r = -ENODEV; + goto fail2; + } ar2->ep[1] = &alt->endpoint[0].desc; r = ati_remote2_urb_init(ar2); if (r) - goto fail2; + goto fail3; ar2->channel_mask = channel_mask; ar2->mode_mask = mode_mask; r = ati_remote2_setup(ar2, ar2->channel_mask); if (r) - goto fail2; + goto fail3; usb_make_path(udev, ar2->phys, sizeof(ar2->phys)); strlcat(ar2->phys, "/input0", sizeof(ar2->phys)); @@ -845,11 +868,11 @@ static int ati_remote2_probe(struct usb_interface *interface, const struct usb_d r = sysfs_create_group(&udev->dev.kobj, &ati_remote2_attr_group); if (r) - goto fail2; + goto fail3; r = ati_remote2_input_init(ar2); if (r) - goto fail3; + goto fail4; usb_set_intfdata(interface, ar2); @@ -857,10 +880,11 @@ static int ati_remote2_probe(struct usb_interface *interface, const struct usb_d return 0; - fail3: + fail4: sysfs_remove_group(&udev->dev.kobj, &ati_remote2_attr_group); - fail2: + fail3: ati_remote2_urb_cleanup(ar2); + fail2: usb_driver_release_interface(&ati_remote2_driver, ar2->intf[1]); fail1: kfree(ar2);