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=-6.8 required=3.0 tests=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=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 9190FC43603 for ; Mon, 16 Dec 2019 18:46:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6062E2082E for ; Mon, 16 Dec 2019 18:46:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576521963; bh=NaWavsSZhFlb4xQQSsr5Jhv73K6/rXkLUuFFF1PQqd4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=SDgyygpLGa8NgqRz09+7rDqXax0TblbgQc88ECRebIMvff5PrCu72VyrzvyIFuzc/ 0A4n6tJhyNQRtk1v7CSVm8EOOEQWzuPRTKZKxu7grjrGN1UdQJQ4pKks+HqG1kBly3 vDQcrOOiVUAqjdVZB4ueGpKcuw5378bOHhwLu+K0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728269AbfLPR4m (ORCPT ); Mon, 16 Dec 2019 12:56:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:54952 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728259AbfLPR4i (ORCPT ); Mon, 16 Dec 2019 12:56:38 -0500 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 AE27C21582; Mon, 16 Dec 2019 17:56:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576518998; bh=NaWavsSZhFlb4xQQSsr5Jhv73K6/rXkLUuFFF1PQqd4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YZv3eL8jUkRbjtKKwAH1gA6zgijeW/c0Ois3gnqWm2VAMHrISi9Wnc+QFCIFKI3zW TBu6nezakmMs7abFsrqgwmWm+bgQWuvwPQR3jDiM8KFwCmf49Ihq8GMmxiYoGq0j4v 5TxWnKI70yCS8H/k0B537g3Or7NPKf18fSa99T30= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+e3f4897236c4eeb8af4f@syzkaller.appspotmail.com, Paolo Bonzini , Ben Hutchings Subject: [PATCH 4.14 154/267] KVM: x86: fix out-of-bounds write in KVM_GET_EMULATED_CPUID (CVE-2019-19332) Date: Mon, 16 Dec 2019 18:48:00 +0100 Message-Id: <20191216174910.932121900@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20191216174848.701533383@linuxfoundation.org> References: <20191216174848.701533383@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: Paolo Bonzini commit 433f4ba1904100da65a311033f17a9bf586b287e upstream. The bounds check was present in KVM_GET_SUPPORTED_CPUID but not KVM_GET_EMULATED_CPUID. Reported-by: syzbot+e3f4897236c4eeb8af4f@syzkaller.appspotmail.com Fixes: 84cffe499b94 ("kvm: Emulate MOVBE", 2013-10-29) Signed-off-by: Paolo Bonzini Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/cpuid.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -404,7 +404,7 @@ static inline int __do_cpuid_ent(struct r = -E2BIG; - if (*nent >= maxnent) + if (WARN_ON(*nent >= maxnent)) goto out; do_cpuid_1_ent(entry, function, index); @@ -707,6 +707,9 @@ out: static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 func, u32 idx, int *nent, int maxnent, unsigned int type) { + if (*nent >= maxnent) + return -E2BIG; + if (type == KVM_GET_EMULATED_CPUID) return __do_cpuid_ent_emulated(entry, func, idx, nent, maxnent);