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=-7.7 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 C1112C04EBF for ; Tue, 4 Dec 2018 10:57:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7CC31214D9 for ; Tue, 4 Dec 2018 10:57:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="m/ItR6a+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7CC31214D9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726849AbeLDK5x (ORCPT ); Tue, 4 Dec 2018 05:57:53 -0500 Received: from mail.kernel.org ([198.145.29.99]:41882 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726382AbeLDK5r (ORCPT ); Tue, 4 Dec 2018 05:57:47 -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 B656E2146D; Tue, 4 Dec 2018 10:57:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543921067; bh=46VBUqWgoLtTRV+CO4Ke7u1zTn6JuBfAbxegj+VMh+g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=m/ItR6a+2khgwWCzPGAXe/xPqG3t4pJxO+ybo/G9Sd2FbMytbZQnNqwTlS1pt9jTG 11pFvrj/Gmt2pZm2UQrNc+PIjM2F44m5ZASnP2nBhkLRCkHDxWYza7fUXWlgKmbMBo 7ttsHDKvMpmQCgOEgzh5YdkIjr3x/+MccvOhtGxE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+a8ef68d71211ba264f56@syzkaller.appspotmail.com, Mark Kanda , Liran Alon , Paolo Bonzini Subject: [PATCH 4.19 066/139] KVM: x86: Fix kernel info-leak in KVM_HC_CLOCK_PAIRING hypercall Date: Tue, 4 Dec 2018 11:49:07 +0100 Message-Id: <20181204103652.761525392@linuxfoundation.org> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181204103649.950154335@linuxfoundation.org> References: <20181204103649.950154335@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 Archived-At: List-Archive: List-Post: 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Liran Alon commit bcbfbd8ec21096027f1ee13ce6c185e8175166f6 upstream. kvm_pv_clock_pairing() allocates local var "struct kvm_clock_pairing clock_pairing" on stack and initializes all it's fields besides padding (clock_pairing.pad[]). Because clock_pairing var is written completely (including padding) to guest memory, failure to init struct padding results in kernel info-leak. Fix the issue by making sure to also init the padding with zeroes. Fixes: 55dd00a73a51 ("KVM: x86: add KVM_HC_CLOCK_PAIRING hypercall") Reported-by: syzbot+a8ef68d71211ba264f56@syzkaller.appspotmail.com Reviewed-by: Mark Kanda Signed-off-by: Liran Alon Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/x86.c | 1 + 1 file changed, 1 insertion(+) --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6788,6 +6788,7 @@ static int kvm_pv_clock_pairing(struct k clock_pairing.nsec = ts.tv_nsec; clock_pairing.tsc = kvm_read_l1_tsc(vcpu, cycle); clock_pairing.flags = 0; + memset(&clock_pairing.pad, 0, sizeof(clock_pairing.pad)); ret = 0; if (kvm_write_guest(vcpu->kvm, paddr, &clock_pairing,