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=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 60A93C433DF for ; Mon, 27 Jul 2020 12:52:52 +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 29762206E7 for ; Mon, 27 Jul 2020 12:52:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="dwIJjcHL" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 29762206E7 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]:47354 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k02cd-0000lS-F2 for qemu-devel@archiver.kernel.org; Mon, 27 Jul 2020 08:52:51 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:44344) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k02br-0008PA-9C for qemu-devel@nongnu.org; Mon, 27 Jul 2020 08:52:03 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:53600 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 1k02bp-0001n8-I9 for qemu-devel@nongnu.org; Mon, 27 Jul 2020 08:52:03 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595854320; 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=ziK62NPFE+h1hWBxVnfPWzQnp4NkUiewSsIzh0Y7llY=; b=dwIJjcHLlXxlZgnD9Jz4JPkHtUBUj91OPcuDxjYGlX4a9TEq6jAych49+wUmJWGEMHTqHU HA2LByaSUft67cPinPyue0cvzAHLxVBEIU652x9tFTlomiJNYh5m37fJCHTe00HGnWa2C9 oSyJgpKX8ZjE4Wh3UOzxsXd32O3nt4U= 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-194-RxHKDfm7NBmm8XEoBsrGeA-1; Mon, 27 Jul 2020 08:51:58 -0400 X-MC-Unique: RxHKDfm7NBmm8XEoBsrGeA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AA60B1005510 for ; Mon, 27 Jul 2020 12:51:57 +0000 (UTC) Received: from jason-ThinkPad-X1-Carbon-6th.redhat.com (ovpn-12-71.pek2.redhat.com [10.72.12.71]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8711710013C0; Mon, 27 Jul 2020 12:51:52 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com, qemu-devel@nongnu.org Subject: [PATCH V2] virtio-net: check the existence of peer before accessing vDPA config Date: Mon, 27 Jul 2020 20:51:50 +0800 Message-Id: <20200727125150.4687-1-jasowang@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=205.139.110.61; envelope-from=jasowang@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/27 01:46:13 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -40 X-Spam_score: -4.1 X-Spam_bar: ---- X-Spam_report: (-4.1 / 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_H2=-1, 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: cohuck@redhat.com, Cindy Lu Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" We try to check whether a peer is VDPA in order to get config from there - with no peer, this leads to a NULL pointer dereference. Add a check before trying to access the peer type. No peer means not VDPA. Fixes: 108a64818e69b ("vhost-vdpa: introduce vhost-vdpa backend") Cc: Cindy Lu Tested-by: Cornelia Huck Reviewed-by: Cornelia Huck Signed-off-by: Jason Wang --- Changes from V1: - Tweak the log - Add the comment in the code --- hw/net/virtio-net.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c index 4895af1cbe..a1fe9e9285 100644 --- a/hw/net/virtio-net.c +++ b/hw/net/virtio-net.c @@ -125,6 +125,7 @@ static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config) { VirtIONet *n = VIRTIO_NET(vdev); struct virtio_net_config netcfg; + NetClientState *nc = qemu_get_queue(n->nic); int ret = 0; memset(&netcfg, 0 , sizeof(struct virtio_net_config)); @@ -142,13 +143,16 @@ static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config) VIRTIO_NET_RSS_SUPPORTED_HASHES); memcpy(config, &netcfg, n->config_size); - NetClientState *nc = qemu_get_queue(n->nic); - if (nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) { + /* + * Is this VDPA? No peer means not VDPA: there's no way to + * disconnect/reconnect a VDPA peer. + */ + if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) { ret = vhost_net_get_config(get_vhost_net(nc->peer), (uint8_t *)&netcfg, - n->config_size); - if (ret != -1) { - memcpy(config, &netcfg, n->config_size); - } + n->config_size); + if (ret != -1) { + memcpy(config, &netcfg, n->config_size); + } } } @@ -156,6 +160,7 @@ static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config) { VirtIONet *n = VIRTIO_NET(vdev); struct virtio_net_config netcfg = {}; + NetClientState *nc = qemu_get_queue(n->nic); memcpy(&netcfg, config, n->config_size); @@ -166,11 +171,14 @@ static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config) qemu_format_nic_info_str(qemu_get_queue(n->nic), n->mac); } - NetClientState *nc = qemu_get_queue(n->nic); - if (nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) { - vhost_net_set_config(get_vhost_net(nc->peer), (uint8_t *)&netcfg, - 0, n->config_size, - VHOST_SET_CONFIG_TYPE_MASTER); + /* + * Is this VDPA? No peer means not VDPA: there's no way to + * disconnect/reconnect a VDPA peer. + */ + if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_VDPA) { + vhost_net_set_config(get_vhost_net(nc->peer), + (uint8_t *)&netcfg, 0, n->config_size, + VHOST_SET_CONFIG_TYPE_MASTER); } } -- 2.20.1