From patchwork Thu Dec 7 14:55:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Albert Esteve X-Patchwork-Id: 13483392 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 44047C4167B for ; Thu, 7 Dec 2023 14:57:05 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rBFnD-0000QE-Uh; Thu, 07 Dec 2023 09:56:00 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rBFnB-0000Q2-F3 for qemu-devel@nongnu.org; Thu, 07 Dec 2023 09:55:57 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rBFn8-0003py-1z for qemu-devel@nongnu.org; Thu, 07 Dec 2023 09:55:57 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1701960951; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=USj2+qT/n6WeZx783xFOJ1a/OTnmQweQXultk8j1NQg=; b=MI3G3ppLlxmiUXB/SygGGYoq9X+E3LxMdRbo724hETMdxytZD6spY8JL5F43u3kev0o/6t PdkSHDw02BTWPSEzKVbvKE5ls1hFrJ6x29zkwv/u67IO6B79e3QRPxa6jEo05ZKz0Od7qG 9EQpc0PZc88Z13zpHFli7upVIxWLg0c= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-237-pceHpKMSPZ6fz2At2ANHrA-1; Thu, 07 Dec 2023 09:55:50 -0500 X-MC-Unique: pceHpKMSPZ6fz2At2ANHrA-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id EF4EF85A58B; Thu, 7 Dec 2023 14:55:49 +0000 (UTC) Received: from fedora.redhat.com (unknown [10.45.224.225]) by smtp.corp.redhat.com (Postfix) with ESMTP id 68B3C492BC6; Thu, 7 Dec 2023 14:55:48 +0000 (UTC) From: Albert Esteve To: qemu-devel@nongnu.org Cc: marcandre.lureau@gmail.com, kraxel@redhat.com, "Michael S. Tsirkin" , stefanha@gmail.com, Albert Esteve Subject: [PATCH v2 1/3] hw/virtio: check owner for removing objects Date: Thu, 7 Dec 2023 15:55:43 +0100 Message-ID: <20231207145545.783877-2-aesteve@redhat.com> In-Reply-To: <20231207145545.783877-1-aesteve@redhat.com> References: <20231207145545.783877-1-aesteve@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.9 Received-SPF: pass client-ip=170.10.129.124; envelope-from=aesteve@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Shared objects lack spoofing protection. For VHOST_USER_BACKEND_SHARED_OBJECT_REMOVE messages received by the vhost-user interface, any backend was allowed to remove entries from the shared table just by knowing the UUID. Only the owner of the entry shall be allowed to removed their resources from the table. To fix that, add a check for all *SHARED_OBJECT_REMOVE messages received. A vhost device can only remove TYPE_VHOST_DEV entries that are owned by them, otherwise skip the removal, and inform the device that the entry has not been removed in the answer. Signed-off-by: Albert Esteve --- hw/virtio/vhost-user.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index f214df804b..1c3f2357be 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -1611,11 +1611,27 @@ vhost_user_backend_handle_shared_object_add(struct vhost_dev *dev, } static int -vhost_user_backend_handle_shared_object_remove(VhostUserShared *object) +vhost_user_backend_handle_shared_object_remove(struct vhost_dev *dev, + VhostUserShared *object) { QemuUUID uuid; memcpy(uuid.data, object->uuid, sizeof(object->uuid)); + switch (virtio_object_type(&uuid)) { + case TYPE_VHOST_DEV: + { + struct vhost_dev *owner = virtio_lookup_vhost_device(&uuid); + if (owner == NULL || dev != owner) { + /* Not allowed to remove non-owned entries */ + return 0; + } + break; + } + default: + /* Not allowed to remove non-owned entries */ + return 0; + } + return virtio_remove_resource(&uuid); } @@ -1794,7 +1810,8 @@ static gboolean backend_read(QIOChannel *ioc, GIOCondition condition, ret = vhost_user_backend_handle_shared_object_add(dev, &payload.object); break; case VHOST_USER_BACKEND_SHARED_OBJECT_REMOVE: - ret = vhost_user_backend_handle_shared_object_remove(&payload.object); + ret = vhost_user_backend_handle_shared_object_remove(dev, + &payload.object); break; case VHOST_USER_BACKEND_SHARED_OBJECT_LOOKUP: ret = vhost_user_backend_handle_shared_object_lookup(dev->opaque, ioc,