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=-5.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 9F302C433DF for ; Mon, 18 May 2020 16:00:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6AE3C20758 for ; Mon, 18 May 2020 16:00:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="GlQ/qV4t" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728216AbgERP77 (ORCPT ); Mon, 18 May 2020 11:59:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43630 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728199AbgERP77 (ORCPT ); Mon, 18 May 2020 11:59:59 -0400 Received: from mail-pg1-x541.google.com (mail-pg1-x541.google.com [IPv6:2607:f8b0:4864:20::541]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49294C061A0C for ; Mon, 18 May 2020 08:59:59 -0700 (PDT) Received: by mail-pg1-x541.google.com with SMTP id f6so5044580pgm.1 for ; Mon, 18 May 2020 08:59:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=vViKERqJOakH8p/LEYiawGQY0S7vLNAgpEZTrLwRx60=; b=GlQ/qV4thuYPpmWSFEMqRsvpgOYmr8Xw2AMRTHLXsU/yToWQqqs+bOSPby5hgvFJzX /VH2jV2ieC/ngXNA4IKzkhiuTm7h45oQtLkCyl7wPniY88HyVb1G06jP0NXQD9kK/ZEC OtZwykFwRtZVt+IQryJCfjCpj4qb9hqQPBLIcYckxzMe/Bgaag4PiPq94Bj1RB1HyUzu UG0pfDIHdo4E2/Lk+OR79ZjHEIJyva/Omsw2+BmpeFgUOqe6+hmIDeZZpq8l9m6AJlnN 9m/kHX1OVuYVUa0lN8u+/gaD/6oltleA9RFJP/bNzkG1Ac7djsGLL3z4Pb1WrmN6l63S 03wg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=vViKERqJOakH8p/LEYiawGQY0S7vLNAgpEZTrLwRx60=; b=S+1TQiQdyMn33jY5c7lL55KNlMwh0hAg/JXn23LfEJaDDFn94YP49IRtLjld9TUJ3B 7LWXbdn/36Al4XRunyD+F6fgjykDrGWnPTBzpEwYi/ozlrWWxSFomhoYJg6yvu6dw0oe psVObWMtlxs4tcF+5wb7DTigTDZo0Q2NiXtcsHuBM0v+MZTkGKs4F6L1OGyonnp8my3O aqyjn3mHIu7Q9VNlrCnRzCeSbGy62zzuam8Od1rWQ/l+s2WxcyWbTk9U8vT9sUo1/x4e ik+sOHCPr9bm3QFqRG0tw0W0ES5zRmZsXKRMS7nad3/FlEUZ0IHTyIyo/uqhESmCOG/g dOCQ== X-Gm-Message-State: AOAM530AujX3iqjjQnRzRUZTMg1aicuTvqbC9e1lT0xaGw+V9j344SjK BnOQVjTB9uftlAHDwiaa0/QA+RsA X-Google-Smtp-Source: ABdhPJyiMLlmVrQsL8iXOMr7WKupx0no+6NAlg1q23EgL5ANDyTpmweb1axBUy2bKpflz+xXq+SolQ== X-Received: by 2002:a65:51c7:: with SMTP id i7mr15651562pgq.382.1589817598553; Mon, 18 May 2020 08:59:58 -0700 (PDT) Received: from [192.168.86.235] (c-73-241-150-58.hsd1.ca.comcast.net. [73.241.150.58]) by smtp.gmail.com with ESMTPSA id d18sm3265921pfq.136.2020.05.18.08.59.57 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 18 May 2020 08:59:57 -0700 (PDT) Subject: Re: [PATCH net] __netif_receive_skb_core: pass skb by reference To: Boris Sukholitko , netdev@vger.kernel.org References: <20200518090152.GA10405@noodle> From: Eric Dumazet Message-ID: <22579c6e-76e2-51f3-5911-819784cd30cf@gmail.com> Date: Mon, 18 May 2020 08:59:56 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200518090152.GA10405@noodle> 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 5/18/20 2:01 AM, Boris Sukholitko wrote: > __netif_receive_skb_core may change the skb pointer passed into it (e.g. > in rx_handler). The original skb may be freed as a result of this > operation. > > The callers of __netif_receive_skb_core may further process original skb > by using pt_prev pointer returned by __netif_receive_skb_core thus > leading to unpleasant effects. > > The solution is to pass skb by reference into __netif_receive_skb_core. > > Signed-off-by: Boris Sukholitko Please provide a Fixes: tag for such a scary patch. Thanks.