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=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 AFB3AC433F8 for ; Mon, 27 Jul 2020 14:37:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8D670206E7 for ; Mon, 27 Jul 2020 14:37:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595860646; bh=wgQ+dqjWde6gj5sHLIy3LyLTb5h2Ed0FJyVL+Tfcgec=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=aGYCDKgI1i1nAwUM5EkSoPyLYU1r4UcY7AHuJgFJ19Kk8B9SkOYKTfCRfBhXirjSP sI4pyFj0gsnFxXOQEgAZpIrLLA04jP66DyvF89MQiFu4zE7tqesL5wSZEp3mg1n1kW VuAAOOnpOgcu/OJ5PiPYn0nOdFxjefDp3AIsM04Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730131AbgG0OhY (ORCPT ); Mon, 27 Jul 2020 10:37:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:37118 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729643AbgG0OMk (ORCPT ); Mon, 27 Jul 2020 10:12:40 -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 B7B562073E; Mon, 27 Jul 2020 14:12:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595859160; bh=wgQ+dqjWde6gj5sHLIy3LyLTb5h2Ed0FJyVL+Tfcgec=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AFD8zuYifIJmC24ZTkvxmzxqxcsmjeZS7rVm3cQ94gMAz0HdnOT0USSPUb2NHPVQ+ /Msaxlk9mUdCVToqoFlViHYijkPhMOUOFQt+j7OOj5Xmnv1nSBdKTDWe/CRGCaGaR2 gbheZkJ12ruy7ho1cqJ2esPj8PJ3FQmfK8fJMZv4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ian Abbott Subject: [PATCH 4.19 69/86] staging: comedi: addi_apci_1564: check INSN_CONFIG_DIGITAL_TRIG shift Date: Mon, 27 Jul 2020 16:04:43 +0200 Message-Id: <20200727134917.880081083@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200727134914.312934924@linuxfoundation.org> References: <20200727134914.312934924@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: Ian Abbott commit 926234f1b8434c4409aa4c53637aa3362ca07cea upstream. The `INSN_CONFIG` comedi instruction with sub-instruction code `INSN_CONFIG_DIGITAL_TRIG` includes a base channel in `data[3]`. This is used as a right shift amount for other bitmask values without being checked. Shift amounts greater than or equal to 32 will result in undefined behavior. Add code to deal with this. Fixes: 1e15687ea472 ("staging: comedi: addi_apci_1564: add Change-of-State interrupt subdevice and required functions") Cc: #3.17+ Signed-off-by: Ian Abbott Link: https://lore.kernel.org/r/20200717145257.112660-4-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/addi_apci_1564.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) --- a/drivers/staging/comedi/drivers/addi_apci_1564.c +++ b/drivers/staging/comedi/drivers/addi_apci_1564.c @@ -331,14 +331,22 @@ static int apci1564_cos_insn_config(stru unsigned int *data) { struct apci1564_private *devpriv = dev->private; - unsigned int shift, oldmask; + unsigned int shift, oldmask, himask, lomask; switch (data[0]) { case INSN_CONFIG_DIGITAL_TRIG: if (data[1] != 0) return -EINVAL; shift = data[3]; - oldmask = (1U << shift) - 1; + if (shift < 32) { + oldmask = (1U << shift) - 1; + himask = data[4] << shift; + lomask = data[5] << shift; + } else { + oldmask = 0xffffffffu; + himask = 0; + lomask = 0; + } switch (data[2]) { case COMEDI_DIGITAL_TRIG_DISABLE: devpriv->ctrl = 0; @@ -362,8 +370,8 @@ static int apci1564_cos_insn_config(stru devpriv->mode2 &= oldmask; } /* configure specified channels */ - devpriv->mode1 |= data[4] << shift; - devpriv->mode2 |= data[5] << shift; + devpriv->mode1 |= himask; + devpriv->mode2 |= lomask; break; case COMEDI_DIGITAL_TRIG_ENABLE_LEVELS: if (devpriv->ctrl != (APCI1564_DI_IRQ_ENA | @@ -380,8 +388,8 @@ static int apci1564_cos_insn_config(stru devpriv->mode2 &= oldmask; } /* configure specified channels */ - devpriv->mode1 |= data[4] << shift; - devpriv->mode2 |= data[5] << shift; + devpriv->mode1 |= himask; + devpriv->mode2 |= lomask; break; default: return -EINVAL;