From patchwork Thu Jun 11 19:43:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 11600743 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 263AA13B1 for ; Thu, 11 Jun 2020 20:24:50 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F159A2074B for ; Thu, 11 Jun 2020 20:24:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="egwZe2cP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F159A2074B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:39270 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jjTkn-0005N0-7o for patchwork-qemu-devel@patchwork.kernel.org; Thu, 11 Jun 2020 16:24:49 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55608) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jjT9x-000130-Jy for qemu-devel@nongnu.org; Thu, 11 Jun 2020 15:46:45 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:21617 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jjT9v-0001Jo-MQ for qemu-devel@nongnu.org; Thu, 11 Jun 2020 15:46:45 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591904803; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=29AlYbIXVBIeOwrHqg3LZpvYsZ2xsGsqiqZLm2UcVxg=; b=egwZe2cPIgIfg72fpIYq+TLpgoDnCDjuPiJ3Zp0GJMU0InKwp7/QMwpIP0RvO7X0rjiOf1 HyEdM3MLL/ymxqLbo/DYT0EBKrbKR6oR3DcVFxDSqyHQgG8Lr+lN3fgtKBIqey8uwPlkvG EZ/ZUR+co2Whc5kW6LvoHfHIHJXuVPs= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-148-U950Cc47Mm2BJra5LfFzoA-1; Thu, 11 Jun 2020 15:45:31 -0400 X-MC-Unique: U950Cc47Mm2BJra5LfFzoA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 102AC107ACCA; Thu, 11 Jun 2020 19:45:30 +0000 (UTC) Received: from virtlab701.virt.lab.eng.bos.redhat.com (virtlab701.virt.lab.eng.bos.redhat.com [10.19.152.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8DFD35C1B2; Thu, 11 Jun 2020 19:45:29 +0000 (UTC) From: Paolo Bonzini To: qemu-devel@nongnu.org Subject: [PULL 047/115] i386/kvm: fix a use-after-free when vcpu plug/unplug Date: Thu, 11 Jun 2020 15:43:41 -0400 Message-Id: <20200611194449.31468-48-pbonzini@redhat.com> In-Reply-To: <20200611194449.31468-1-pbonzini@redhat.com> References: <20200611194449.31468-1-pbonzini@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=205.139.110.61; envelope-from=pbonzini@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/11 14:57:53 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -30 X-Spam_score: -3.1 X-Spam_bar: --- X-Spam_report: (-3.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Igor Mammedov , Pan Nengyuan , Euler Robot Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Pan Nengyuan When we hotplug vcpus, cpu_update_state is added to vm_change_state_head in kvm_arch_init_vcpu(). But it forgot to delete in kvm_arch_destroy_vcpu() after unplug. Then it will cause a use-after-free access. This patch delete it in kvm_arch_destroy_vcpu() to fix that. Reproducer: virsh setvcpus vm1 4 --live virsh setvcpus vm1 2 --live virsh suspend vm1 virsh resume vm1 The UAF stack: ==qemu-system-x86_64==28233==ERROR: AddressSanitizer: heap-use-after-free on address 0x62e00002e798 at pc 0x5573c6917d9e bp 0x7fff07139e50 sp 0x7fff07139e40 WRITE of size 1 at 0x62e00002e798 thread T0 #0 0x5573c6917d9d in cpu_update_state /mnt/sdb/qemu/target/i386/kvm.c:742 #1 0x5573c699121a in vm_state_notify /mnt/sdb/qemu/vl.c:1290 #2 0x5573c636287e in vm_prepare_start /mnt/sdb/qemu/cpus.c:2144 #3 0x5573c6362927 in vm_start /mnt/sdb/qemu/cpus.c:2150 #4 0x5573c71e8304 in qmp_cont /mnt/sdb/qemu/monitor/qmp-cmds.c:173 #5 0x5573c727cb1e in qmp_marshal_cont qapi/qapi-commands-misc.c:835 #6 0x5573c7694c7a in do_qmp_dispatch /mnt/sdb/qemu/qapi/qmp-dispatch.c:132 #7 0x5573c7694c7a in qmp_dispatch /mnt/sdb/qemu/qapi/qmp-dispatch.c:175 #8 0x5573c71d9110 in monitor_qmp_dispatch /mnt/sdb/qemu/monitor/qmp.c:145 #9 0x5573c71dad4f in monitor_qmp_bh_dispatcher /mnt/sdb/qemu/monitor/qmp.c:234 Reported-by: Euler Robot Signed-off-by: Pan Nengyuan Reviewed-by: Philippe Mathieu-Daudé Message-Id: <20200513132630.13412-1-pannengyuan@huawei.com> Reviewed-by: Igor Mammedov Signed-off-by: Paolo Bonzini --- target/i386/cpu.h | 1 + target/i386/kvm.c | 4 +++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/target/i386/cpu.h b/target/i386/cpu.h index 00d1f4f013..37572bd437 100644 --- a/target/i386/cpu.h +++ b/target/i386/cpu.h @@ -1634,6 +1634,7 @@ struct X86CPU { CPUNegativeOffsetState neg; CPUX86State env; + VMChangeStateEntry *vmsentry; uint64_t ucode_rev; diff --git a/target/i386/kvm.c b/target/i386/kvm.c index 95bbeb424b..ef2e0a81dd 100644 --- a/target/i386/kvm.c +++ b/target/i386/kvm.c @@ -1741,7 +1741,7 @@ int kvm_arch_init_vcpu(CPUState *cs) } } - qemu_add_vm_change_state_handler(cpu_update_state, env); + cpu->vmsentry = qemu_add_vm_change_state_handler(cpu_update_state, env); c = cpuid_find_entry(&cpuid_data.cpuid, 1, 0); if (c) { @@ -1852,6 +1852,8 @@ int kvm_arch_destroy_vcpu(CPUState *cs) env->nested_state = NULL; } + qemu_del_vm_change_state_handler(cpu->vmsentry); + return 0; }