From patchwork Wed Aug 12 10:49:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 276700 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=-8.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, MIME_BASE64_TEXT,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 51B8CC433DF for ; Wed, 12 Aug 2020 10:51:30 +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 1C40820781 for ; Wed, 12 Aug 2020 10:51:30 +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="C+VwDs5Y" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1C40820781 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]:55424 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k5oLx-0005b3-1K for qemu-devel@archiver.kernel.org; Wed, 12 Aug 2020 06:51:29 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33518) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k5oKN-0003tq-KE for qemu-devel@nongnu.org; Wed, 12 Aug 2020 06:49:51 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:29422 helo=us-smtp-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 1k5oKK-0007AI-KN for qemu-devel@nongnu.org; Wed, 12 Aug 2020 06:49:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1597229388; 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=jQ45tqp8SaqX8OfuFH3rp5Q3ZXUef2GT5+Omm/cVV9g=; b=C+VwDs5YtisYavIdndrAVJ19R5VCusq3J11vWPtgQgFqng+/+t18/XxgXZ/ufR/LE7LKAj ZGSzgAGvouhYgSklO+o+a9Tf06Fs7/SyuDorKNTIgcq/UTfPdhEEnPm9nWCCcpph1Raa/t GovL1ENArp9UbUYtaaB4hjwlE6d2o3I= 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-93-1niw20NON0-i_PXqcQxOJw-1; Wed, 12 Aug 2020 06:49:46 -0400 X-MC-Unique: 1niw20NON0-i_PXqcQxOJw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E4F1C101C8A0; Wed, 12 Aug 2020 10:49:44 +0000 (UTC) Received: from localhost (ovpn-114-96.ams2.redhat.com [10.36.114.96]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7CF4060C84; Wed, 12 Aug 2020 10:49:44 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [PATCH 3/3] virtio-crypto: don't modify elem->in/out_sg Date: Wed, 12 Aug 2020 11:49:18 +0100 Message-Id: <20200812104918.107116-4-stefanha@redhat.com> In-Reply-To: <20200812104918.107116-1-stefanha@redhat.com> References: <20200812104918.107116-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0.001 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.120; envelope-from=stefanha@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/12 06:16:38 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -13 X-Spam_score: -1.4 X-Spam_bar: - X-Spam_report: (-1.4 / 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, MIME_BASE64_TEXT=1.741, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham 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: Kevin Wolf , qemu-block@nongnu.org, "Michael S. Tsirkin" , Max Reitz , Alexander Bulekov , "Gonglei \(Arei\)" , Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" A number of iov_discard_front/back() operations are made by virtio-crypto. The elem->in/out_sg iovec arrays are modified by these operations, resulting virtqueue_unmap_sg() calls on different addresses than were originally mapped. This is problematic because dirty memory may not be logged correctly, MemoryRegion refcounts may be leaked, and the non-RAM bounce buffer can be leaked. Take a copy of the elem->in/out_sg arrays so that the originals are preserved. The iov_discard_undo() API could be used instead (with better performance) but requires careful auditing of the code, so do the simple thing instead. Signed-off-by: Stefan Hajnoczi --- hw/virtio/virtio-crypto.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c index 6da12e315f..54f9bbb789 100644 --- a/hw/virtio/virtio-crypto.c +++ b/hw/virtio/virtio-crypto.c @@ -228,6 +228,8 @@ static void virtio_crypto_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) size_t s; for (;;) { + g_autofree struct iovec *out_iov_copy = NULL; + elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); if (!elem) { break; @@ -240,9 +242,12 @@ static void virtio_crypto_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) } out_num = elem->out_num; - out_iov = elem->out_sg; + out_iov_copy = g_memdup(elem->out_sg, sizeof(out_iov[0]) * out_num); + out_iov = out_iov_copy; + in_num = elem->in_num; in_iov = elem->in_sg; + if (unlikely(iov_to_buf(out_iov, out_num, 0, &ctrl, sizeof(ctrl)) != sizeof(ctrl))) { virtio_error(vdev, "virtio-crypto request ctrl_hdr too short"); @@ -582,6 +587,8 @@ virtio_crypto_handle_request(VirtIOCryptoReq *request) int queue_index = virtio_crypto_vq2q(virtio_get_queue_index(request->vq)); struct virtio_crypto_op_data_req req; int ret; + g_autofree struct iovec *in_iov_copy = NULL; + g_autofree struct iovec *out_iov_copy = NULL; struct iovec *in_iov; struct iovec *out_iov; unsigned in_num; @@ -598,9 +605,13 @@ virtio_crypto_handle_request(VirtIOCryptoReq *request) } out_num = elem->out_num; - out_iov = elem->out_sg; + out_iov_copy = g_memdup(elem->out_sg, sizeof(out_iov[0]) * out_num); + out_iov = out_iov_copy; + in_num = elem->in_num; - in_iov = elem->in_sg; + in_iov_copy = g_memdup(elem->in_sg, sizeof(in_iov[0]) * in_num); + in_iov = in_iov_copy; + if (unlikely(iov_to_buf(out_iov, out_num, 0, &req, sizeof(req)) != sizeof(req))) { virtio_error(vdev, "virtio-crypto request outhdr too short");