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=-4.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 CB84AC433E0 for ; Wed, 17 Feb 2021 14:20:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 97B0C64DE0 for ; Wed, 17 Feb 2021 14:20:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233411AbhBQOUy (ORCPT ); Wed, 17 Feb 2021 09:20:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46420 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233314AbhBQOUu (ORCPT ); Wed, 17 Feb 2021 09:20:50 -0500 Received: from mail-wm1-x32f.google.com (mail-wm1-x32f.google.com [IPv6:2a00:1450:4864:20::32f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1FFD4C0613D6 for ; Wed, 17 Feb 2021 06:20:10 -0800 (PST) Received: by mail-wm1-x32f.google.com with SMTP id m1so3788320wml.2 for ; Wed, 17 Feb 2021 06:20:10 -0800 (PST) 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=ywt1nEYmK/lJrv+dpVUIxvRl7CzNbXX4ooSFLhqf+yg=; b=tkLpKCMjRBlLWCCi3IoS5cMr3GooHjtpUl1PXhRx+yq6iaNDI/zagtAl1kCXum4+TW tGmKIZs6GifP2bcRA3uq3dTSxTE1aReJnli3OBZg9IxXzJFvr5aErZWqwJimBzZZmVPK Fpu39+UHCCzcKVp7EV4+d2cIqz0oVc93s1BWSCHfbK0DMjuF+BBCeohH9/jqLng37lax fXQEqpzyjOHmbwAJnaB+opIfTCEnnXSlBPrKOrkDBIpIEC0wra7qJ+v3APKlOH3jtcmI 9gxJ21+sFKwrI9EhRSzjM/sTJbXmCAq/11xh1KU5psbfYw78I6hFypiY027XNWZt56Oz lacw== 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=ywt1nEYmK/lJrv+dpVUIxvRl7CzNbXX4ooSFLhqf+yg=; b=NuRQs2pB3fbU93Z7XVngSWr+OT9Q/ctX+mIgbodNy9sreMAR3UoRsmS9ZYJpzI6GCk HPNSaI+Pq7ufR5q0/aMGRqgbUCToNz3lSG0lxgG9A2KUUf+hbLELbGEfCGhbQLMwCaCm TG0zKzSJUEC33Px171WigmfLmRG1BMhvIOkcZCCwP5LiG7gXsH8+Q7V0EN6NHmiiKaQt 1EoLuzHuXLDAKWyhuKXRmo0CroIMoz8nhme0jhww9nD/VwhKbkI009j9sPsn5YbU6iPx inxOlzTU9TAiTsQOu6v92Vy2ZmovhQyuxZGXWuH/2kqeq56n7NS9uvYB2S2XaSo94Qlw vE5Q== X-Gm-Message-State: AOAM533KGehJB8JxybDHPK3C+O4ZjLf8uBdClKRuK/BnaytK4G5ToHYv JlxGctbRwcrDNptV6qHExEI= X-Google-Smtp-Source: ABdhPJwLcpzlTBs9aGA2y+F/DF67AUTecRuO0Fc6Lk8xQLcvlqS08Cz5UmM7eN2Ha0OdD1L0zsQvNQ== X-Received: by 2002:a05:600c:21ca:: with SMTP id x10mr7540743wmj.94.1613571608837; Wed, 17 Feb 2021 06:20:08 -0800 (PST) Received: from ?IPv6:2003:ea:8f39:5b00:3459:b70a:ad7d:c95e? (p200300ea8f395b003459b70aad7dc95e.dip0.t-ipconnect.de. [2003:ea:8f39:5b00:3459:b70a:ad7d:c95e]) by smtp.googlemail.com with ESMTPSA id s23sm3312399wmc.29.2021.02.17.06.20.07 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 17 Feb 2021 06:20:08 -0800 (PST) Subject: Re: [PATCH] net: dsa: tag_rtl4_a: Support also egress tags To: Vladimir Oltean , DENG Qingfang Cc: Linus Walleij , Andrew Lunn , Vivien Didelot , Florian Fainelli , "David S . Miller" , Jakub Kicinski , netdev , Mauri Sandberg References: <20210216235542.2718128-1-linus.walleij@linaro.org> <20210217124239.sxgkhow53vox7o54@skbuf> From: Heiner Kallweit Message-ID: Date: Wed, 17 Feb 2021 15:19:59 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <20210217124239.sxgkhow53vox7o54@skbuf> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 17.02.2021 13:42, Vladimir Oltean wrote: > On Wed, Feb 17, 2021 at 08:38:30PM +0800, DENG Qingfang wrote: >> On Wed, Feb 17, 2021 at 7:55 AM Linus Walleij wrote: >>> + >>> + /* Pad out to at least 60 bytes */ >>> + if (unlikely(eth_skb_pad(skb))) >>> + return NULL; >> >> I just found that this will cause double free (eth_skb_pad will free >> the skb if allocation fails, and dsa_slave_xmit will still try to free >> it because it returns NULL. >> Replace eth_skb_pad(skb) with __skb_put_padto(skb, ETH_ZLEN, false) to >> avoid that. > That's really a pitfall. I had to do the same in r8169: cc6528bc9a0c ("r8169: fix potential skb double free in an error path") > Good catch, Qingfang. >