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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 1476CC04AB6 for ; Tue, 28 May 2019 21:02:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE026208CB for ; Tue, 28 May 2019 21:02:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="b6ySIiie" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727703AbfE1VCg (ORCPT ); Tue, 28 May 2019 17:02:36 -0400 Received: from mail-pg1-f177.google.com ([209.85.215.177]:36959 "EHLO mail-pg1-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727070AbfE1VCg (ORCPT ); Tue, 28 May 2019 17:02:36 -0400 Received: by mail-pg1-f177.google.com with SMTP id n27so11708584pgm.4 for ; Tue, 28 May 2019 14:02:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=c7ceyE43Xyn0ahYiGYoW3/Ms+/K6shUmeLNiiKXE+ls=; b=b6ySIiieuUqst46NfU1GbbB6HCVA/8E9t2dCEiU8Ipft08V/GPmVh/EXk51OawJ3GU C3ujodI+Xy11iocGsJW+tqhIFQpA1YjPQ8VnZdzDBgsts3v5D45i6OzV9n92L0HbE5u4 9GLgpA4BPErbLHr4tAZahm0GtFue4P0yyYvVvNxRaOCZGfOzyKZoVm1uJaCqCELCizzw 8jLRmO+H9WGPAqQeXS/SwR5XwCg8S49HKbBpbpTCiuvZsRGgWUZG1R0Cdud6Wnl8BTJF No+32G8viI4dMbVACmyEPgSxKZ9gwOBrI0pVTLKVLqSkWLdMrylRNEct9N/s27Z18LEL VPcg== 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-language :content-transfer-encoding; bh=c7ceyE43Xyn0ahYiGYoW3/Ms+/K6shUmeLNiiKXE+ls=; b=sShARVMSCibzJIWhRo7QLWWrTO00OPon6FIrNtEJCzzOr0WRHyJYCNjIS4GGnirRsK rXrfLAGCdF/oIZ9rCzF7fuauCXF2pkprEQefp/CP4RuYAx4cL3g/2Ri+V4joROAjiVvq 2MfrTx8K5ZvxPedzgPslzR9A6gBpJheOBs1q8YAhwuUHsxIaWCxc74MGEnP/whQic+/+ OW+ov3uDxd4LFpaLctw15qRP5RmkTFvFK0ws/fHm0kQr+GOlJP2peGneHfhtPIzBFEKe 04D30+I1hGPkyxpW13sMDXBdE8v/zWJj7tAiBb0xnchG++xCNHmPS4Isp3nNsrfrJPX2 PuLQ== X-Gm-Message-State: APjAAAWoj/kAvTc8irGdWd/jHxuZkiI8/v/wWxEMCKOxaLPX5scMSQM1 StOfEnpK3XbPvEb3JrIlyl4= X-Google-Smtp-Source: APXvYqyMU7cycacggdcQpLy+VRgdeavqnTSMV3DGIOJPUSOqgtpxdu2GHWoS0KA4uQq+b7qGDbyb8Q== X-Received: by 2002:a62:75d8:: with SMTP id q207mr112759856pfc.35.1559077356004; Tue, 28 May 2019 14:02:36 -0700 (PDT) Received: from ?IPv6:2620:15c:2c1:200:55c7:81e6:c7d8:94b? ([2620:15c:2c1:200:55c7:81e6:c7d8:94b]) by smtp.gmail.com with ESMTPSA id n9sm15701406pfq.53.2019.05.28.14.02.34 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Tue, 28 May 2019 14:02:35 -0700 (PDT) Subject: Re: [PATCH net] net/sched: act_pedit: fix 'ex munge' on network header in case of QinQ packet To: Davide Caratti , Cong Wang , Jiri Pirko , Jamal Hadi Salim , "David S. Miller" , netdev@vger.kernel.org Cc: shuali@redhat.com, Eli Britstein References: <753b96cc340e4fbae6640da070aac09d7220efe2.1559075758.git.dcaratti@redhat.com> From: Eric Dumazet Message-ID: <290a8e03-1d24-a84f-751c-6fc27f04bba0@gmail.com> Date: Tue, 28 May 2019 14:02:33 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <753b96cc340e4fbae6640da070aac09d7220efe2.1559075758.git.dcaratti@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 5/28/19 1:50 PM, Davide Caratti wrote: > Like it has been done in commit 2ecba2d1e45b ("net: sched: act_csum: Fix > csum calc for tagged packets"), also 'pedit' needs to adjust the network > offset when multiple tags are present in the packets: otherwise wrong IP > headers (but good checksums) can be observed with the following command: ... > +again: > + switch (protocol) { > + case cpu_to_be16(ETH_P_8021AD): /* fall through */ > + case cpu_to_be16(ETH_P_8021Q): > + if (skb_vlan_tag_present(skb) && > + !orig_vlan_tag_present) { > + protocol = skb->protocol; > + orig_vlan_tag_present = true; > + } else { > + struct vlan_hdr *vlan; > + > + vlan = (struct vlan_hdr *)skb->data; > + protocol = vlan->h_vlan_encapsulated_proto; > + skb_pull(skb, VLAN_HLEN); > + skb_reset_network_header(skb); > + (*vlan_hdr_count)++; > + } > + goto again; What prevents this loop to access data not yet in skb->head ? skb_header_pointer() (or pskb_may_pull()) seems needed.