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=-3.6 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,URIBL_BLOCKED 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 A85A8C433DF for ; Thu, 21 May 2020 18:14:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F0B820823 for ; Thu, 21 May 2020 18:14:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="JbzOnF5M" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729166AbgEUSOl (ORCPT ); Thu, 21 May 2020 14:14:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33858 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728067AbgEUSOl (ORCPT ); Thu, 21 May 2020 14:14:41 -0400 Received: from mail-lj1-x242.google.com (mail-lj1-x242.google.com [IPv6:2a00:1450:4864:20::242]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B6DDCC061A0E; Thu, 21 May 2020 11:14:40 -0700 (PDT) Received: by mail-lj1-x242.google.com with SMTP id q2so9410403ljm.10; Thu, 21 May 2020 11:14:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=9vLy+sx+oAPc7Ja7vaMG7FVwptnedVW1W80n6Fglj54=; b=JbzOnF5MezQA32NFHdcvalEHBU6t6vFpbGEGNV+6pWn+CV/UNgU4Hrq5pWWRUvk9GE nsbC4VrCUIf5MDbeJ8rlVmC9l4ElCb8MxVNl3lDLoKdFtq0svtlpJzA6R9nl3H0w5gZ5 31Rxs+ktfLPG+YVZAteE1B5dV436UEWEQ17hojebX7nzmvt+iQWVJcfekYNpToZovLEc oiKluEAySzWfSlqBxB20L3wFQWzeRvLCCK9xfxPmUrVW+FiIXOAo+DG6s+uxdDvF2T3a 7xW7wTKD16Om5WWSqkV/lOlqvO+FhPbgGNBtoTqStlL2Td93CpncUhi06aSMY3TVK3Yx GbAA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=9vLy+sx+oAPc7Ja7vaMG7FVwptnedVW1W80n6Fglj54=; b=ae6bqrdXLW6Wl4gbMFmJgFdOIlK8LxecdCakuQCIQJZxqoXIk/5KVjCUcDx4F5mZ/+ jBf0+jCDVTmjVXLL6P9qoQDGdq7WyDYmH428G4symUYZkvBcMzAOoDGgmFHdaUDVuyxu 5LCM8IsCxWe43cVBCiRDwafcpAcisvSwuolbrtm/y9M6viO8btxYvgJRQyfEyCWUczXB ENbngIwX0LjfvlmNlYkQZUDWtXddVSEG+XHlBj+utTJPD3kLAxFEDYN+3tR+d2KIJad2 jkzBaDx3ZsiR7BE1BE4a5SzaXGCUQxum1pkf5SKCNSFYbjmwxXEbyRV3quKjJ9iw+/PS 2VPQ== X-Gm-Message-State: AOAM530kJdowC7zfCa8vOnzsxzQ1pE1cwgv0SxBdsSMyy7nFPhMyV0zt mKoVWhCVlGzD/eLYQYWMOpt2DryjzT9szIxN88dkJg== X-Google-Smtp-Source: ABdhPJw474zeMwSEONV3S9BYNqdgoywLW8609QV6HtK4Y7FMsNVrvX+9UD+b6YEZcX3E0+OahC4YrZ10ztRhwKiFo4I= X-Received: by 2002:a2e:9549:: with SMTP id t9mr5857291ljh.283.1590084879084; Thu, 21 May 2020 11:14:39 -0700 (PDT) MIME-Version: 1.0 References: <20200521083435.560256-1-jakub@cloudflare.com> <20200521152111.GB49942@google.com> In-Reply-To: <20200521152111.GB49942@google.com> From: Alexei Starovoitov Date: Thu, 21 May 2020 11:14:27 -0700 Message-ID: Subject: Re: [PATCH bpf v2] flow_dissector: Drop BPF flow dissector prog ref on netns cleanup To: Stanislav Fomichev Cc: Jakub Sitnicki , bpf , Network Development , kernel-team Content-Type: text/plain; charset="UTF-8" Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Thu, May 21, 2020 at 8:21 AM wrote: > > On 05/21, Jakub Sitnicki wrote: > > When attaching a flow dissector program to a network namespace with > > bpf(BPF_PROG_ATTACH, ...) we grab a reference to bpf_prog. > > > If netns gets destroyed while a flow dissector is still attached, and > > there > > are no other references to the prog, we leak the reference and the program > > remains loaded. > > > Leak can be reproduced by running flow dissector tests from selftests/bpf: > > > # bpftool prog list > > # ./test_flow_dissector.sh > > ... > > selftests: test_flow_dissector [PASS] > > # bpftool prog list > > 4: flow_dissector name _dissect tag e314084d332a5338 gpl > > loaded_at 2020-05-20T18:50:53+0200 uid 0 > > xlated 552B jited 355B memlock 4096B map_ids 3,4 > > btf_id 4 > > # > > > Fix it by detaching the flow dissector program when netns is going away. > > > Fixes: d58e468b1112 ("flow_dissector: implements flow dissector BPF hook") > > Signed-off-by: Jakub Sitnicki > Reviewed-by: Stanislav Fomichev Applied. Thanks