From mboxrd@z Thu Jan 1 00:00:00 1970 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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 391F6C433E8 for ; Mon, 20 Jul 2020 15:42:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 19B4320773 for ; Mon, 20 Jul 2020 15:42:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595259731; bh=i6z5wAOGKay2yoCvdUnPgPzFvWJm4qfzKtRJ0+eiRlg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=dn/UULaQkz5eoIyxx13VwDbZCd1NY2KWp2PqzCe2LVHnBK/8kcjyFqFUlH/BzkwQm DmvvS6Gcyuu/ySqFbHiyozU2dcqaiBy+qQk5V7teTtmZNg8DZNpJ/VTh3WE4icPCR6 ZHw3HwlMcU4XmXUji9a0kA/pfLKWVZ5VLPxg0FcU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730020AbgGTPmJ (ORCPT ); Mon, 20 Jul 2020 11:42:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:34528 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729977AbgGTPmA (ORCPT ); Mon, 20 Jul 2020 11:42:00 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 178BD2064B; Mon, 20 Jul 2020 15:41:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595259719; bh=i6z5wAOGKay2yoCvdUnPgPzFvWJm4qfzKtRJ0+eiRlg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mYqlehPalEAi9lH9kZLdkT+KJ0GE9aP8TZc3nb+vMpY2QdUTUqJG+iaBySuwsbn7z rLcUZpa0PCJeBMKwllog7IH0/Dj5SbLy7wIzFOXwyRbCMbm1WYa3f78G/se/ZZE1uA Ilf6HrdW9N/ozAsmtZSdBfKCRKERzMf25h+JNI68= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Ian Abbott , Sasha Levin Subject: [PATCH 4.9 55/86] staging: comedi: verify array index is correct before using it Date: Mon, 20 Jul 2020 17:36:51 +0200 Message-Id: <20200720152755.928515742@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200720152753.138974850@linuxfoundation.org> References: <20200720152753.138974850@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Carpenter [ Upstream commit ef75e14a6c935eec82abac07ab68e388514e39bc ] This code reads from the array before verifying that "trig" is a valid index. If the index is wildly out of bounds then reading from an invalid address could lead to an Oops. Fixes: a8c66b684efa ("staging: comedi: addi_apci_1500: rewrite the subdevice support functions") Signed-off-by: Dan Carpenter Reviewed-by: Ian Abbott Link: https://lore.kernel.org/r/20200709102936.GA20875@mwanda Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/staging/comedi/drivers/addi_apci_1500.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/staging/comedi/drivers/addi_apci_1500.c b/drivers/staging/comedi/drivers/addi_apci_1500.c index 63991c49ff230..79a8799b12628 100644 --- a/drivers/staging/comedi/drivers/addi_apci_1500.c +++ b/drivers/staging/comedi/drivers/addi_apci_1500.c @@ -465,9 +465,9 @@ static int apci1500_di_cfg_trig(struct comedi_device *dev, unsigned int lo_mask = data[5] << shift; unsigned int chan_mask = hi_mask | lo_mask; unsigned int old_mask = (1 << shift) - 1; - unsigned int pm = devpriv->pm[trig] & old_mask; - unsigned int pt = devpriv->pt[trig] & old_mask; - unsigned int pp = devpriv->pp[trig] & old_mask; + unsigned int pm; + unsigned int pt; + unsigned int pp; if (trig > 1) { dev_dbg(dev->class_dev, @@ -480,6 +480,10 @@ static int apci1500_di_cfg_trig(struct comedi_device *dev, return -EINVAL; } + pm = devpriv->pm[trig] & old_mask; + pt = devpriv->pt[trig] & old_mask; + pp = devpriv->pp[trig] & old_mask; + switch (data[2]) { case COMEDI_DIGITAL_TRIG_DISABLE: /* clear trigger configuration */ -- 2.25.1