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=-5.5 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_PASS,USER_AGENT_MUTT 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 821D6C43387 for ; Fri, 18 Jan 2019 16:50:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E87C20823 for ; Fri, 18 Jan 2019 16:50:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=fomichev-me.20150623.gappssmtp.com header.i=@fomichev-me.20150623.gappssmtp.com header.b="ERAL5FZd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727779AbfARQuh (ORCPT ); Fri, 18 Jan 2019 11:50:37 -0500 Received: from mail-pf1-f193.google.com ([209.85.210.193]:38907 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727489AbfARQug (ORCPT ); Fri, 18 Jan 2019 11:50:36 -0500 Received: by mail-pf1-f193.google.com with SMTP id q1so6868381pfi.5 for ; Fri, 18 Jan 2019 08:50:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fomichev-me.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=HcftPW4s9AG2TofBcZKckes+3bviuGx1MjlHEiqbuj8=; b=ERAL5FZdkMWkROsQUYo+RoZm99zc7KqRRT+zbBjYnKMl4lBq5rd596kT4sTprBl0eV 9pTxxGCvWitZIcRlBCjUwiekwAatBkG/cQAbUsXm0gMM+n6FiBRT8r6wPdh4OFboU0mg KNdfqH/eVZoYzquntqCerxj5qwqmC3O7dTOMni1Kgz+6GI6qfnBVFSM/F8p/fpwI57KD BGkNaE5VPanXIHwIF/mICY2h5O9HQGqFwVkSZ7ndKPna6UUYEGXrYg1/8VBJE/iMHIgE lNA52PZRuLe6CwJvnC8c61EPeFahOwHbYWu8vQfKeiNI8ZmCDZYn1lnEZVVgaCxj267w 5ySQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=HcftPW4s9AG2TofBcZKckes+3bviuGx1MjlHEiqbuj8=; b=BOTNa/MPTI/67+ECvfzi7T76X/KUtaweAdKDcp2JtA/8lCzN0YnDrlrnp2MO/cHmTh Q+WsrpvPCd2sS8ksyFjAr5BJ3QUN+ljF5NLgkQP2jXjuqyoDx2eRoQziAWX0LHDWlzIG c8h7SKaJHAbOioI4oN4XHNdkgfQkBnUVOAksk0w0n9qnjVQ9ec0ZnnG+vAISN3UsF7Bq f7qCCTr8ZgdfJ4xqAgHZld/H3kA/33CYYsmvYSagbqU+isacarXOrz8sGpG4tBJVrK80 X6o9aTYiPWumXXmE7eLwA2pjow9eom6W2bFJslPkM05f5pG3jThnd+p0Pfo4ee9F1Br2 RoIg== X-Gm-Message-State: AJcUukejutNIN7g2IHzPfAV7Ruvd1t7OdwphOq1TKepFRJ2dpB7Wqvg/ oDdtCs3de72NxOEiINKAG6OSwQ== X-Google-Smtp-Source: ALg8bN6LOE41tmgtnBtXSIG7A4VGDkGwsUlwl+HizvD6mDr36/f/sMW2lV53jLAM4UdaOiqO4v3KxQ== X-Received: by 2002:a62:3888:: with SMTP id f130mr19746360pfa.132.1547830235135; Fri, 18 Jan 2019 08:50:35 -0800 (PST) Received: from localhost ([2601:646:8f00:18d9:d0fa:7a4b:764f:de48]) by smtp.gmail.com with ESMTPSA id c13sm11152746pfe.93.2019.01.18.08.50.33 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 18 Jan 2019 08:50:34 -0800 (PST) Date: Fri, 18 Jan 2019 08:50:33 -0800 From: Stanislav Fomichev To: Andrey Ignatov Cc: Stanislav Fomichev , "netdev@vger.kernel.org" , "davem@davemloft.net" , "ast@kernel.org" , "daniel@iogearbox.net" , edumazet@google.com Subject: Re: [PATCH bpf-next 0/5] add bpf cgroup hooks that trigger on socket close Message-ID: <20190118165033.GA26773@mini-arch> References: <20190118004106.163825-1-sdf@google.com> <20190118023654.GB8342@rdna-mbp.dhcp.thefacebook.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190118023654.GB8342@rdna-mbp.dhcp.thefacebook.com> User-Agent: Mutt/1.11.2 (2019-01-07) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 01/18, Andrey Ignatov wrote: > Stanislav Fomichev [Thu, 2019-01-17 16:41 -0800]: > > Currently, we have BPF_CGROUP_INET_SOCK_CREATE hook that triggers on > > socket creation and there is no way to know when the socket is being > > closed. Add new set of hooks BPF_CGROUP_INET{4,6}_SOCK_RELEASE > > that trigger when the socket is closed. > > > > Initial intended usecase is to cleanup statistics after POST{4,6}_BIND. > > Hooks have read-only access to all fields of struct bpf_sock. > > Do you need it for both TCP and UDP? Yes, we need both TCP and UDP. Although, UDP is tricky in general with the connected/unconnected cases. > I was thinking about this hook earlier but since in my case only TCP was > needed I ended up using TCP-BPF. E.g. be BPF_SOCK_OPS_TCP_LISTEN_CB or > BPF_SOCK_OPS_TCP_CONNECT_CB can be used instead of POST{4,6}_BIND to > enable something, and then BPF_SOCK_OPS_STATE_CB can be used instead of > SOCK_RELEASE to disable that something when socket transisions to > BPF_TCP_CLOSE (e.g. BPF_TCP_LISTEN -> BPF_TCP_CLOSE). > > That turned out to be much cleaner than POST{4,6}_BIND and also works > fine when socket is disconnected with AF_UNSPEC and then connected again > (what Eric mentioned). What if we do something like the patch below? Add pre_release hook (like we currently have for pre_connect) and call it from connect(AF_UNSPEC) and from inet_release? Any concerns here? (I agree that TCP is probably better handled via BPF_SOCK_OPS_TCP_XYZ hooks, but we need something for UDP as well) -- diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index b703ad242365..ee3dc181df8f 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -568,8 +568,11 @@ int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr, if (addr_len < sizeof(uaddr->sa_family)) return -EINVAL; - if (uaddr->sa_family == AF_UNSPEC) + if (uaddr->sa_family == AF_UNSPEC) { + if (BPF_CGROUP_PRE_RELEASE_ENABLED(sk)) + sk->sk_prot->pre_release(sk); return sk->sk_prot->disconnect(sk, flags); + } if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) { err = sk->sk_prot->pre_connect(sk, uaddr, addr_len); @@ -632,6 +635,8 @@ int __inet_stream_connect(struct socket *sock, struct sockaddr *uaddr, return -EINVAL; if (uaddr->sa_family == AF_UNSPEC) { + if (BPF_CGROUP_PRE_RELEASE_ENABLED(sk)) + sk->sk_prot->pre_release(sk); err = sk->sk_prot->disconnect(sk, flags); sock->state = err ? SS_DISCONNECTING : SS_UNCONNECTED; goto out; > > First patch adds hooks, the rest of the patches add uapi and tests to make > > sure these hooks work. > > > > Stanislav Fomichev (5): > > bpf: add BPF_CGROUP_INET{4,6}_SOCK_RELEASE hooks > > tools: bpf: support BPF_CGROUP_INET{4,6}_SOCK_RELEASE in > > libbpf/bpftool > > selftests/bpf: add BPF_CGROUP_INET{4,6}_SOCK_RELEASE to > > test_section_names.c > > selftests/bpf: add BPF_CGROUP_INET{4,6}_SOCK_RELEASE to test_sock.c > > selftests/bpf: add BPF_CGROUP_INET{4,6}_SOCK_RELEASE to > > test_sock_addr.c > > > > include/linux/bpf-cgroup.h | 6 + > > include/net/inet_common.h | 1 + > > include/uapi/linux/bpf.h | 2 + > > kernel/bpf/syscall.c | 8 ++ > > net/core/filter.c | 7 + > > net/ipv4/af_inet.c | 13 +- > > net/ipv6/af_inet6.c | 5 +- > > tools/bpf/bpftool/cgroup.c | 2 + > > tools/include/uapi/linux/bpf.h | 2 + > > tools/lib/bpf/libbpf.c | 4 + > > .../selftests/bpf/test_section_names.c | 10 ++ > > tools/testing/selftests/bpf/test_sock.c | 119 ++++++++++++++++ > > tools/testing/selftests/bpf/test_sock_addr.c | 131 +++++++++++++++++- > > 13 files changed, 307 insertions(+), 3 deletions(-) > > > > -- > > 2.20.1.321.g9e740568ce-goog > > > > -- > Andrey Ignatov