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=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 1AC1AC433DB for ; Mon, 1 Feb 2021 06:07:43 +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 64D8F64E2F for ; Mon, 1 Feb 2021 06:07:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 64D8F64E2F 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+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:38436 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l6SNB-0005EI-2E for qemu-devel@archiver.kernel.org; Mon, 01 Feb 2021 01:07:41 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:47622) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l6SMF-0004fq-QI for qemu-devel@nongnu.org; Mon, 01 Feb 2021 01:06:43 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:33453) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l6SMC-0007Ik-G8 for qemu-devel@nongnu.org; Mon, 01 Feb 2021 01:06:43 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612159598; 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=5RSZmL8s19fWZdZMsxGxac+DUCKkw9B0P1eYyaNAl/U=; b=CTRQ68NupRh2CKscZMt+g9EzsX8eu1m2D8frSuuKr1B1kSYWnium/XqcGDBmWdznXOS0wJ VqkFL7S2TTkcjYOo/nwVqIDaJUB2+q/GA3gc9bKJN53xKItdIKgqkGc+Sd7dPo35Cgvu0A +9QjJuoGXy9jqgPBn8GIOR9ATyGZY4s= 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-595-bT8LE8mgOB2iyYRoV0nePw-1; Mon, 01 Feb 2021 01:06:36 -0500 X-MC-Unique: bT8LE8mgOB2iyYRoV0nePw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id CB2448042A3; Mon, 1 Feb 2021 06:06:35 +0000 (UTC) Received: from [10.72.13.120] (ovpn-13-120.pek2.redhat.com [10.72.13.120]) by smtp.corp.redhat.com (Postfix) with ESMTP id F1D5C5D9DC; Mon, 1 Feb 2021 06:06:27 +0000 (UTC) Subject: Re: [PATCH] vhost: Check for valid vdev in vhost_backend_handle_iotlb_msg To: =?UTF-8?Q?Eugenio_P=c3=a9rez?= , qemu-devel@nongnu.org References: <20210129090728.831208-1-eperezma@redhat.com> From: Jason Wang Message-ID: <28b3542c-1f58-cc8a-be77-c2317aa75089@redhat.com> Date: Mon, 1 Feb 2021 14:06:25 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210129090728.831208-1-eperezma@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jasowang@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Received-SPF: pass client-ip=216.205.24.124; envelope-from=jasowang@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.351, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.079, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no 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: maxime.coquelin@redhat.com, qemu-stable@nongnu.org, "Michael S. Tsirkin" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 2021/1/29 下午5:07, Eugenio Pérez wrote: > Not checking this can lead to invalid dev->vdev member access in > vhost_device_iotlb_miss if backend issue an iotlb message in a bad > timing, either maliciously or by a bug. > > Reproduced rebooting a guest with testpmd in txonly forward mode. > #0 0x0000559ffff94394 in vhost_device_iotlb_miss ( > dev=dev@entry=0x55a0012f6680, iova=10245279744, write=1) > at ../hw/virtio/vhost.c:1013 > #1 0x0000559ffff9ac31 in vhost_backend_handle_iotlb_msg ( > imsg=0x7ffddcfd32c0, dev=0x55a0012f6680) > at ../hw/virtio/vhost-backend.c:411 > #2 vhost_backend_handle_iotlb_msg (dev=dev@entry=0x55a0012f6680, > imsg=imsg@entry=0x7ffddcfd32c0) > at ../hw/virtio/vhost-backend.c:404 > #3 0x0000559fffeded7b in slave_read (opaque=0x55a0012f6680) > at ../hw/virtio/vhost-user.c:1464 > #4 0x000055a0000c541b in aio_dispatch_handler ( > ctx=ctx@entry=0x55a0010a2120, node=0x55a0012d9e00) > at ../util/aio-posix.c:329 > > Fixes: 6dcdd06e3b ("spec/vhost-user spec: Add IOMMU support") > Signed-off-by: Eugenio Pérez Acked-by: Jason Wang > --- > hw/virtio/vhost-backend.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c > index 222bbcc62d..31b33bde37 100644 > --- a/hw/virtio/vhost-backend.c > +++ b/hw/virtio/vhost-backend.c > @@ -406,6 +406,11 @@ int vhost_backend_handle_iotlb_msg(struct vhost_dev *dev, > { > int ret = 0; > > + if (unlikely(!dev->vdev)) { > + error_report("Unexpected IOTLB message when virtio device is stopped"); > + return -EINVAL; > + } > + > switch (imsg->type) { > case VHOST_IOTLB_MISS: > ret = vhost_device_iotlb_miss(dev, imsg->iova,