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=-7.0 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=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 CA053C43387 for ; Fri, 28 Dec 2018 11:54:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9913820879 for ; Fri, 28 Dec 2018 11:54:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545998051; bh=jL2JHwpEpYLiZKXLvgWWJInnjOUuvqNVC+PBvnlGyyM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Lur2dOr3OyU6FOeccwFlO+Mmb8YafK+HAVV/a+W7Cr+gfMT/bzp0423+RoIM166kr zlowk+JiPanbuX4+Yu6+IDE6Z5ENKjVgwLpLa6rlIbdDLnuSMKnQi5ETDk/d4NOiGw mcPnoHe7cjMsexZbSisFmcT7+XDhJ6xjHjC3VnWc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732326AbeL1Lxm (ORCPT ); Fri, 28 Dec 2018 06:53:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:53584 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727378AbeL1Lxm (ORCPT ); Fri, 28 Dec 2018 06:53:42 -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 563732148E; Fri, 28 Dec 2018 11:53:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1545998021; bh=jL2JHwpEpYLiZKXLvgWWJInnjOUuvqNVC+PBvnlGyyM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GKPByK+V2wrE7/VwwiwOmtOwHWgr50ajM4rBDhOhlh36oJPMdEt1xJlqCEn1MbGZN qf32XAlDQF19qL/l5UK/1ju0PHC5MzT7egKTgoxpcU5KV1g4Th7x2qfHWiLOjyapoA zFxWqeNTezbRAtzfj0YBm/TcYC2D3BCxSm5bzoqQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+39810e6c400efadfef71@syzkaller.appspotmail.com, Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Wanpeng Li Subject: [PATCH 4.19 21/46] KVM: X86: Fix NULL deref in vcpu_scan_ioapic Date: Fri, 28 Dec 2018 12:52:15 +0100 Message-Id: <20181228113126.008457453@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20181228113124.971620049@linuxfoundation.org> References: <20181228113124.971620049@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 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wanpeng Li commit dcbd3e49c2f0b2c2d8a321507ff8f3de4af76d7c upstream. Reported by syzkaller: CPU: 1 PID: 5962 Comm: syz-executor118 Not tainted 4.20.0-rc6+ #374 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:kvm_apic_hw_enabled arch/x86/kvm/lapic.h:169 [inline] RIP: 0010:vcpu_scan_ioapic arch/x86/kvm/x86.c:7449 [inline] RIP: 0010:vcpu_enter_guest arch/x86/kvm/x86.c:7602 [inline] RIP: 0010:vcpu_run arch/x86/kvm/x86.c:7874 [inline] RIP: 0010:kvm_arch_vcpu_ioctl_run+0x5296/0x7320 arch/x86/kvm/x86.c:8074 Call Trace: kvm_vcpu_ioctl+0x5c8/0x1150 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2596 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The reason is that the testcase writes hyperv synic HV_X64_MSR_SINT14 msr and triggers scan ioapic logic to load synic vectors into EOI exit bitmap. However, irqchip is not initialized by this simple testcase, ioapic/apic objects should not be accessed. This patch fixes it by also considering whether or not apic is present. Reported-by: syzbot+39810e6c400efadfef71@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Cc: Paolo Bonzini Cc: Radim Krčmář Signed-off-by: Wanpeng Li Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/x86.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7304,7 +7304,7 @@ void kvm_make_scan_ioapic_request(struct static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu) { - if (!kvm_apic_hw_enabled(vcpu->arch.apic)) + if (!kvm_apic_present(vcpu)) return; bitmap_zero(vcpu->arch.ioapic_handled_vectors, 256);