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=-17.5 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 738D3C4743C for ; Wed, 23 Jun 2021 03:45:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4706460FD8 for ; Wed, 23 Jun 2021 03:45:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230174AbhFWDrc (ORCPT ); Tue, 22 Jun 2021 23:47:32 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:36591 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229774AbhFWDrb (ORCPT ); Tue, 22 Jun 2021 23:47:31 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1624419914; 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=zRO9M68B1N+iUNIIknyesktneXdWBFn4ufwTcOykBZg=; b=AhFnsvIV76reESiFdA++kagVp1DtEig1M7guKlUxd2V7y5T57xiu6VNQYVppQsMl5rBG1/ Sfk8EYqOZcJ1fevc9T833HMLwFM8iW8+ChDPzIvx+h3sgqfOwU8LtB+ShNkug8vMePKGnE rqtKRWGgVDWd0yR392A09+Z8ABDlRqw= Received: from mail-pl1-f197.google.com (mail-pl1-f197.google.com [209.85.214.197]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-398-ZOkqT-VFOWK8WpbTwUZgNA-1; Tue, 22 Jun 2021 23:45:12 -0400 X-MC-Unique: ZOkqT-VFOWK8WpbTwUZgNA-1 Received: by mail-pl1-f197.google.com with SMTP id 62-20020a1709020544b0290116739a77a4so334768plf.7 for ; Tue, 22 Jun 2021 20:45:12 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=zRO9M68B1N+iUNIIknyesktneXdWBFn4ufwTcOykBZg=; b=Nu9Hdo437DO/wQeYcMcjZpnzz6PEld9RPn7F6eSFM7Xfw8wfVdv4CgZGJ4yCYre19a Jrom+nqvtKoMQ9IIBCZzeBdBIkntad69m5wScKc8rEtNaiQjy9hCSzVgy235kRUguld5 o+PvxcPJiDPZq1a9hfLqf29iXnLPLph1BjBJtD5JeGem3zxdsBbBz+WoJKtsdn7LeNYg 4jOcjWxnEpVG19Zk1g3oTkteFK95/UZnRzzl1+ySBxCBfp8Y7NxWoC+WGFOB8VkcNROV 8dFQrJGKT0UlZmUvZ4VxBu0FQVvWG63eYF3QQqFOnGRyqOnJEQPtVzcapG+XnXJk0hyq C5GA== X-Gm-Message-State: AOAM532vHpJINC8lh0DKShv3ACXXDAP0HhMhs6ZkGyuqeqrp+OF3uhk9 gaOQ/pGkOwN8iU0F79UR5bjVolmZS0lij24mlgTNqUKlADV/emD7ulFH13adhNC82RmZqVB+ijf 5Nf368CWu/rDsuKrg X-Received: by 2002:a17:90b:a4d:: with SMTP id gw13mr7378687pjb.104.1624419911616; Tue, 22 Jun 2021 20:45:11 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwxFqS7ubsJQfj4eUKMay2yhZshrB/Ikx5Se0fw5yi5YILch4xMHX63qczK3Qb17MW+OaNNRA== X-Received: by 2002:a17:90b:a4d:: with SMTP id gw13mr7378673pjb.104.1624419911344; Tue, 22 Jun 2021 20:45:11 -0700 (PDT) Received: from wangxiaodeMacBook-Air.local ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id y13sm20612981pgp.16.2021.06.22.20.45.09 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 22 Jun 2021 20:45:10 -0700 (PDT) Subject: Re: [PATCH v2 1/4] net: tun: fix tun_xdp_one() for IFF_TUN mode To: David Woodhouse , netdev@vger.kernel.org Cc: =?UTF-8?Q?Eugenio_P=c3=a9rez?= References: <03ee62602dd7b7101f78e0802249a6e2e4c10b7f.camel@infradead.org> <20210622161533.1214662-1-dwmw2@infradead.org> From: Jason Wang Message-ID: Date: Wed, 23 Jun 2021 11:45:07 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <20210622161533.1214662-1-dwmw2@infradead.org> Content-Type: text/plain; charset=gbk; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org ÔÚ 2021/6/23 ÉÏÎç12:15, David Woodhouse дµÀ: > From: David Woodhouse > > In tun_get_user(), skb->protocol is either taken from the tun_pi header > or inferred from the first byte of the packet in IFF_TUN mode, while > eth_type_trans() is called only in the IFF_TAP mode where the payload > is expected to be an Ethernet frame. > > The alternative path in tun_xdp_one() was unconditionally using > eth_type_trans(), which corrupts packets in IFF_TUN mode. Fix it to > do the correct thing for IFF_TUN mode, as tun_get_user() does. > > Fixes: 043d222f93ab ("tuntap: accept an array of XDP buffs through sendmsg()") > Signed-off-by: David Woodhouse > --- > drivers/net/tun.c | 44 +++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 43 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c > index 4cf38be26dc9..f812dcdc640e 100644 > --- a/drivers/net/tun.c > +++ b/drivers/net/tun.c > @@ -2394,8 +2394,50 @@ static int tun_xdp_one(struct tun_struct *tun, > err = -EINVAL; > goto out; > } > + switch (tun->flags & TUN_TYPE_MASK) { > + case IFF_TUN: > + if (tun->flags & IFF_NO_PI) { > + u8 ip_version = skb->len ? (skb->data[0] >> 4) : 0; > + > + switch (ip_version) { > + case 4: > + skb->protocol = htons(ETH_P_IP); > + break; > + case 6: > + skb->protocol = htons(ETH_P_IPV6); > + break; > + default: > + atomic_long_inc(&tun->dev->rx_dropped); > + kfree_skb(skb); > + err = -EINVAL; > + goto out; > + } > + } else { > + struct tun_pi *pi = (struct tun_pi *)skb->data; > + if (!pskb_may_pull(skb, sizeof(*pi))) { > + atomic_long_inc(&tun->dev->rx_dropped); > + kfree_skb(skb); > + err = -ENOMEM; > + goto out; > + } > + skb_pull_inline(skb, sizeof(*pi)); > + skb->protocol = pi->proto; As replied in previous version, it would be better if we can unify similar logic in tun_get_user(). Thanks > + } > + > + skb_reset_mac_header(skb); > + skb->dev = tun->dev; > + break; > + case IFF_TAP: > + if (!pskb_may_pull(skb, ETH_HLEN)) { > + atomic_long_inc(&tun->dev->rx_dropped); > + kfree_skb(skb); > + err = -ENOMEM; > + goto out; > + } > + skb->protocol = eth_type_trans(skb, tun->dev); > + break; > + } > > - skb->protocol = eth_type_trans(skb, tun->dev); > skb_reset_network_header(skb); > skb_probe_transport_header(skb); > skb_record_rx_queue(skb, tfile->queue_index);