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=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 DA3CEC54FD0 for ; Fri, 24 Apr 2020 14:10:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B6BE920700 for ; Fri, 24 Apr 2020 14:10:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="iX+x0hfy" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727784AbgDXOKG (ORCPT ); Fri, 24 Apr 2020 10:10:06 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:39731 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726993AbgDXOKG (ORCPT ); Fri, 24 Apr 2020 10:10:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1587737404; 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=9Q24/Cv4pcX9vIZJCefwPpasOYfyPgu54YOF/qyScso=; b=iX+x0hfyvhIbSQoWiBVC5ktqrExGw3T3KC/gBqeEgJPo/mkc8iA6kllqGQaVIzycPqTqZl L6b/rw+tK3r+jX3IR5m80RX6w2LxsGbHEbLIxRsqqzlg5xgAcNgwa/moV7KiIy/FPA5xCp Oi8LEL6qCbk71LwJBFLujo4liJ2T9sY= Received: from mail-lf1-f70.google.com (mail-lf1-f70.google.com [209.85.167.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-476-apQYQGsDOd6JW9-wxIt-3g-1; Fri, 24 Apr 2020 10:10:03 -0400 X-MC-Unique: apQYQGsDOd6JW9-wxIt-3g-1 Received: by mail-lf1-f70.google.com with SMTP id v6so3956065lfi.6 for ; Fri, 24 Apr 2020 07:10:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version:content-transfer-encoding; bh=9Q24/Cv4pcX9vIZJCefwPpasOYfyPgu54YOF/qyScso=; b=Nl8jsVi+6eWrNoBHbiYZi5zqD+DAmY4t67d0Va+cpThoBOu68Ip97kn2arik5+mRiO QsElawOmeLGFRbQvPbmxNP9qTcHnigCdiGDV4qKNQa4nH6FfJFT0yJ3Ou+2XBLryuIBN 09fww0yAGJHuVwjdb3hdquniyJin2r/xiriKaYz3GlYoZIxd7Uy4JiQ6ZEar+jSk7/mC Oy/9SYqA/hzI6CIMiq+ZZJNAtKL+bmbjyft5BmYDn2VHBVjAEgYY+0xDMBwXsnER1yPW 3npQRWDfijvspFS8J8qjPHGJjvWZrRLpesCx2rnzArveRoAS0OnDdjAjPfO4eUnAyJ9L i5dw== X-Gm-Message-State: AGi0PuY5TWgX77UhvpEcP6vLp+/IferRGoPMgG1rbZm4DNEdxIJ7LWv2 4MnnTJwzvIT8V+RBP1ZUIAc08l7bJSs9rA0ITEiCKgMabu52Kgi1DEQ9gUnOrVL7Kn9jApHI+F+ pBHs5OH3ckgI+ X-Received: by 2002:a2e:9a93:: with SMTP id p19mr5702468lji.77.1587737401826; Fri, 24 Apr 2020 07:10:01 -0700 (PDT) X-Google-Smtp-Source: APiQypIFrCM8GUhbtFpBrUIy12fsocbDRJMdhvHelGZHzZK4+D07R3UTsAvB5y+4JQ6eoZ+GonblgA== X-Received: by 2002:a2e:9a93:: with SMTP id p19mr5702448lji.77.1587737401609; Fri, 24 Apr 2020 07:10:01 -0700 (PDT) Received: from alrua-x1.borgediget.toke.dk ([2a0c:4d80:42:443::2]) by smtp.gmail.com with ESMTPSA id f4sm4606019lfa.24.2020.04.24.07.10.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 24 Apr 2020 07:10:00 -0700 (PDT) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id 48A4F1814FF; Fri, 24 Apr 2020 16:09:59 +0200 (CEST) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Jesper Dangaard Brouer , sameehj@amazon.com Cc: Jesper Dangaard Brouer , netdev@vger.kernel.org, bpf@vger.kernel.org, zorik@amazon.com, akiyano@amazon.com, gtzalik@amazon.com, Daniel Borkmann , Alexei Starovoitov , John Fastabend , Alexander Duyck , Jeff Kirsher , David Ahern , Willem de Bruijn , Ilias Apalodimas , Lorenzo Bianconi , Saeed Mahameed , steffen.klassert@secunet.com Subject: Re: [PATCH net-next 30/33] xdp: clear grow memory in bpf_xdp_adjust_tail() In-Reply-To: <158757179349.1370371.14581472372520364962.stgit@firesoul> References: <158757160439.1370371.13213378122947426220.stgit@firesoul> <158757179349.1370371.14581472372520364962.stgit@firesoul> X-Clacks-Overhead: GNU Terry Pratchett Date: Fri, 24 Apr 2020 16:09:59 +0200 Message-ID: <87tv192cw8.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Jesper Dangaard Brouer writes: > Clearing memory of tail when grow happens, because it is too easy > to write a XDP_PASS program that extend the tail, which expose > this memory to users that can run tcpdump. > > Signed-off-by: Jesper Dangaard Brouer Probably a good precaution :) Acked-by: Toke H=C3=B8iland-J=C3=B8rgensen