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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 9857CC169C4 for ; Tue, 29 Jan 2019 11:44:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 66B212086C for ; Tue, 29 Jan 2019 11:44:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548762259; bh=1ZdVURTPdG7KAvtF+e4qeXNFxQqbWnSnrWNFzwISORI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=KqGmy2xmNAlIAdmzt4KgkbnLv7M3IPSzvZEQp8dwUw+E9/5eHSCs9Ifdn1YCrLlMn 3tbOJpx/KMzFKSBtlnyqQ2nU3gc2DOP5oXvNtPVKTvtmjWpGtWbVeMtC3UXT46ovYH qbAQlIKYNGaS4Xrqea9d2z+dy7TkFHTeOTk+Tk0k= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730538AbfA2LoS (ORCPT ); Tue, 29 Jan 2019 06:44:18 -0500 Received: from mail.kernel.org ([198.145.29.99]:34494 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729721AbfA2LoP (ORCPT ); Tue, 29 Jan 2019 06:44:15 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.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 04CDF214DA; Tue, 29 Jan 2019 11:44:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548762254; bh=1ZdVURTPdG7KAvtF+e4qeXNFxQqbWnSnrWNFzwISORI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rqRMFLc8Vw6Z7287cTklEX+/uKc+czYm12JyqppGUtMjDQ+J0f0JT4QJCVrNi7QXP YM91dRYG/iItRrB9dF4zJ9+RufOCZBQwpS0pEVL9cAJGKG5scYs6ckTcsOZcXUJNGz NnxnWl/PL2nOL3n8C5ySPKhO22+dBPqnyWocPQJI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH 4.19 043/103] char/mwave: fix potential Spectre v1 vulnerability Date: Tue, 29 Jan 2019 12:35:20 +0100 Message-Id: <20190129113202.080198110@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190129113159.567154026@linuxfoundation.org> References: <20190129113159.567154026@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore 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 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gustavo A. R. Silva commit 701956d4018e5d5438570e39e8bda47edd32c489 upstream. ipcnum is indirectly controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. This issue was detected with the help of Smatch: drivers/char/mwave/mwavedd.c:299 mwave_ioctl() warn: potential spectre issue 'pDrvData->IPCs' [w] (local cap) Fix this by sanitizing ipcnum before using it to index pDrvData->IPCs. Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2 Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Signed-off-by: Greg Kroah-Hartman --- drivers/char/mwave/mwavedd.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/char/mwave/mwavedd.c +++ b/drivers/char/mwave/mwavedd.c @@ -59,6 +59,7 @@ #include #include #include +#include #include "smapi.h" #include "mwavedd.h" #include "3780i.h" @@ -289,6 +290,8 @@ static long mwave_ioctl(struct file *fil ipcnum); return -EINVAL; } + ipcnum = array_index_nospec(ipcnum, + ARRAY_SIZE(pDrvData->IPCs)); PRINTK_3(TRACE_MWAVE, "mwavedd::mwave_ioctl IOCTL_MW_REGISTER_IPC" " ipcnum %x entry usIntCount %x\n", @@ -317,6 +320,8 @@ static long mwave_ioctl(struct file *fil " Invalid ipcnum %x\n", ipcnum); return -EINVAL; } + ipcnum = array_index_nospec(ipcnum, + ARRAY_SIZE(pDrvData->IPCs)); PRINTK_3(TRACE_MWAVE, "mwavedd::mwave_ioctl IOCTL_MW_GET_IPC" " ipcnum %x, usIntCount %x\n", @@ -383,6 +388,8 @@ static long mwave_ioctl(struct file *fil ipcnum); return -EINVAL; } + ipcnum = array_index_nospec(ipcnum, + ARRAY_SIZE(pDrvData->IPCs)); mutex_lock(&mwave_mutex); if (pDrvData->IPCs[ipcnum].bIsEnabled == true) { pDrvData->IPCs[ipcnum].bIsEnabled = false;