Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933306AbcKILgt (ORCPT ); Wed, 9 Nov 2016 06:36:49 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:53876 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932933AbcKILFG (ORCPT ); Wed, 9 Nov 2016 06:05:06 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lars-Peter Clausen , Linus Walleij Subject: [PATCH 4.8 013/138] gpio: GPIO_GET_LINEEVENT_IOCTL: Validate line offset Date: Wed, 9 Nov 2016 11:44:56 +0100 Message-Id: <20161109102845.390397638@linuxfoundation.org> X-Mailer: git-send-email 2.10.2 In-Reply-To: <20161109102844.808685475@linuxfoundation.org> References: <20161109102844.808685475@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1224 Lines: 39 4.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lars-Peter Clausen commit b8b0e3d303654b3bb7b31b0266c513fd6f4132ce upstream. The line offset that is used as an index into the descs array is provided by userspace and might go beyond the bounds of the array. If that happens undefined behavior will occur. Make sure that the offset is within the bounds of the desc array and reject any requests that specify a value outside of it. Fixes: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events") Signed-off-by: Lars-Peter Clausen Signed-off-by: Linus Walleij Signed-off-by: Greg Kroah-Hartman --- drivers/gpio/gpiolib.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -731,6 +731,11 @@ static int lineevent_create(struct gpio_ lflags = eventreq.handleflags; eflags = eventreq.eventflags; + if (offset >= gdev->ngpio) { + ret = -EINVAL; + goto out_free_label; + } + /* This is just wrong: we don't look for events on output lines */ if (lflags & GPIOHANDLE_REQUEST_OUTPUT) { ret = -EINVAL;