From patchwork Tue Jan 2 03:29:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 13508792 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 60661C47074 for ; Tue, 2 Jan 2024 03:30:21 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rKVT5-0004fk-4Q; Mon, 01 Jan 2024 22:29:27 -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 1rKVT3-0004fS-JG for qemu-devel@nongnu.org; Mon, 01 Jan 2024 22:29:25 -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 1rKVT1-00042c-Tf for qemu-devel@nongnu.org; Mon, 01 Jan 2024 22:29:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1704166162; 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; bh=ZptoMoesx/ux09C7cxSVBrOtp5ga2aPVoYXiAiiNAwE=; b=BSjJS8nAY1hj4Lem9X1WnSSED8QIG4yeHqDxO8PG23/LaG2kkFLeTiEmN9NLTspR+zJB7L vVTM9FNpphZqbzG1GUkkcu9gZXBDUmugmFmr3CV+Iv3ZL9+aknm9ScCrmedYKwfv19r8N7 9OFm7AKgh2R5z8b2VcCZPBbFOiyLOBw= 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-195-Ot12dtESNtGyCuj2tbnBTA-1; Mon, 01 Jan 2024 22:29:12 -0500 X-MC-Unique: Ot12dtESNtGyCuj2tbnBTA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (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 EEC7F85A588; Tue, 2 Jan 2024 03:29:11 +0000 (UTC) Received: from localhost.localdomain (unknown [10.72.112.113]) by smtp.corp.redhat.com (Postfix) with ESMTP id D746BC15A0C; Tue, 2 Jan 2024 03:29:04 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, qemu-devel@nongnu.org Cc: Xiao Lei , Yuri Benditovich , qemu-stable@nongnu.org, Mauro Matteo Cascella Subject: [PATCH] virtio-net: correctly copy vnet header when flushing TX Date: Tue, 2 Jan 2024 11:29:01 +0800 Message-ID: <20240102032901.3234-1-jasowang@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.129.124; envelope-from=jasowang@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-2.246, 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=unavailable 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 When HASH_REPORT is negotiated, the guest_hdr_len might be larger than the size of the mergeable rx buffer header. Using virtio_net_hdr_mrg_rxbuf during the header swap might lead a stack overflow in this case. Fixing this by using virtio_net_hdr_v1_hash instead. Reported-by: Xiao Lei Cc: Yuri Benditovich Cc: qemu-stable@nongnu.org Cc: Mauro Matteo Cascella Fixes: CVE-2023-6693 Fixes: e22f0603fb2f ("virtio-net: reference implementation of hash report") Signed-off-by: Jason Wang Reviewed-by: Michael Tokarev --- hw/net/virtio-net.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 80c56f0cfc..73024babd4 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -674,6 +674,11 @@ static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int mergeable_rx_bufs, n->mergeable_rx_bufs = mergeable_rx_bufs; + /* + * Note: when extending the vnet header, please make sure to + * change the vnet header copying logic in virtio_net_flush_tx() + * as well. + */ if (version_1) { n->guest_hdr_len = hash_report ? sizeof(struct virtio_net_hdr_v1_hash) : @@ -2693,7 +2698,7 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q) ssize_t ret; unsigned int out_num; struct iovec sg[VIRTQUEUE_MAX_SIZE], sg2[VIRTQUEUE_MAX_SIZE + 1], *out_sg; - struct virtio_net_hdr_mrg_rxbuf mhdr; + struct virtio_net_hdr_v1_hash vhdr; elem = virtqueue_pop(q->tx_vq, sizeof(VirtQueueElement)); if (!elem) { @@ -2710,7 +2715,7 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q) } if (n->has_vnet_hdr) { - if (iov_to_buf(out_sg, out_num, 0, &mhdr, n->guest_hdr_len) < + if (iov_to_buf(out_sg, out_num, 0, &vhdr, n->guest_hdr_len) < n->guest_hdr_len) { virtio_error(vdev, "virtio-net header incorrect"); virtqueue_detach_element(q->tx_vq, elem, 0); @@ -2718,8 +2723,8 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q) return -EINVAL; } if (n->needs_vnet_hdr_swap) { - virtio_net_hdr_swap(vdev, (void *) &mhdr); - sg2[0].iov_base = &mhdr; + virtio_net_hdr_swap(vdev, (void *) &vhdr); + sg2[0].iov_base = &vhdr; sg2[0].iov_len = n->guest_hdr_len; out_num = iov_copy(&sg2[1], ARRAY_SIZE(sg2) - 1, out_sg, out_num,