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=-10.5 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=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 2DD93C43444 for ; Fri, 11 Jan 2019 15:13:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E7A1D21848 for ; Fri, 11 Jan 2019 15:13:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547219628; bh=p0dcsPsdPGHaiFQTv3TVWw+hfY7vThPhjpH5jn6dC+Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=a9nrRONNvbQXynVvL1EjbTEI/cDBwPpwvekQbgXOVeWRMCpQ5L4ZOl0Gv/tan9cAh 1vU/85VoD683JMrkgX8omFToLfTPWo09MJePjygX5lvf0iS7UVS7CFyjKRGhI181yI UfGrkvr5u9vPR8gGrc1aJyvnRhe9Z6J/ZkgEY3/4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733132AbfAKOOp (ORCPT ); Fri, 11 Jan 2019 09:14:45 -0500 Received: from mail.kernel.org ([198.145.29.99]:58534 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732147AbfAKOOo (ORCPT ); Fri, 11 Jan 2019 09:14:44 -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 8E90220874; Fri, 11 Jan 2019 14:14:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547216084; bh=p0dcsPsdPGHaiFQTv3TVWw+hfY7vThPhjpH5jn6dC+Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uibo/4a8xzjcM7H24lWq2ZhzUVo7FVZt8bHsUw225eIA66e7x1HnXqeOYPTE1S/pK iC47CCmIg22TWCY88DmFneFs4eQ++MAmgXhC78xNfNgU/EteSFEeg6xL69VYn/z02G yIlDeon3zyFZe59DD2d2jApzbuRgv1ciI/P1qq+I= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Colin Ian King , Thomas Gleixner , Tyler Hicks , security@kernel.org Subject: [PATCH 3.18 07/47] x86/mtrr: Dont copy uninitialized gentry fields back to userspace Date: Fri, 11 Jan 2019 15:07:52 +0100 Message-Id: <20190111130957.053666840@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190111130956.170952125@linuxfoundation.org> References: <20190111130956.170952125@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: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Colin Ian King commit 32043fa065b51e0b1433e48d118821c71b5cd65d upstream. Currently the copy_to_user of data in the gentry struct is copying uninitiaized data in field _pad from the stack to userspace. Fix this by explicitly memset'ing gentry to zero, this also will zero any compiler added padding fields that may be in struct (currently there are none). Detected by CoverityScan, CID#200783 ("Uninitialized scalar variable") Fixes: b263b31e8ad6 ("x86, mtrr: Use explicit sizing and padding for the 64-bit ioctls") Signed-off-by: Colin Ian King Signed-off-by: Thomas Gleixner Reviewed-by: Tyler Hicks Cc: security@kernel.org Link: https://lkml.kernel.org/r/20181218172956.1440-1-colin.king@canonical.com Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/mtrr/if.c | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/x86/kernel/cpu/mtrr/if.c +++ b/arch/x86/kernel/cpu/mtrr/if.c @@ -173,6 +173,8 @@ mtrr_ioctl(struct file *file, unsigned i struct mtrr_gentry gentry; void __user *arg = (void __user *) __arg; + memset(&gentry, 0, sizeof(gentry)); + switch (cmd) { case MTRRIOC_ADD_ENTRY: case MTRRIOC_SET_ENTRY: