From patchwork Mon Jul 23 16:53:30 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anton Vasilyev X-Patchwork-Id: 947877 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-gpio-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=ispras.ru Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 41Z6zJ0n5jz9s3q for ; Tue, 24 Jul 2018 02:54:36 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728257AbeGWR4k (ORCPT ); Mon, 23 Jul 2018 13:56:40 -0400 Received: from bran.ispras.ru ([83.149.199.196]:25583 "EHLO smtp.ispras.ru" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728206AbeGWR4k (ORCPT ); Mon, 23 Jul 2018 13:56:40 -0400 Received: from myklebust.intra.ispras.ru (unknown [10.10.2.207]) by smtp.ispras.ru (Postfix) with ESMTP id 8DF12203C3; Mon, 23 Jul 2018 19:54:33 +0300 (MSK) From: Anton Vasilyev To: Linus Walleij Cc: Anton Vasilyev , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, ldv-project@linuxtesting.org Subject: [PATCH] gpio: ml-ioh: Fix buffer underwrite on probe error path Date: Mon, 23 Jul 2018 19:53:30 +0300 Message-Id: <20180723165330.25213-1-vasilyev@ispras.ru> X-Mailer: git-send-email 2.18.0 Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org If ioh_gpio_probe() fails on devm_irq_alloc_descs() then chip may point to any element of chip_save array, so reverse iteration from pointer chip may become chip_save[-1] and gpiochip_remove() will operate with wrong memory. The patch fix the error path of ioh_gpio_probe() to correctly bypass chip_save array. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Anton Vasilyev --- drivers/gpio/gpio-ml-ioh.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpio/gpio-ml-ioh.c b/drivers/gpio/gpio-ml-ioh.c index b23d9a36be1f..51c7d1b84c2e 100644 --- a/drivers/gpio/gpio-ml-ioh.c +++ b/drivers/gpio/gpio-ml-ioh.c @@ -496,9 +496,10 @@ static int ioh_gpio_probe(struct pci_dev *pdev, return 0; err_gpiochip_add: + chip = chip_save; while (--i >= 0) { - chip--; gpiochip_remove(&chip->gpio); + chip++; } kfree(chip_save);