From patchwork Wed Feb 3 04:16:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Cong Wang X-Patchwork-Id: 12063399 X-Patchwork-Delegate: bpf@iogearbox.net 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=-12.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNWANTED_LANGUAGE_BODY, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 722D1C4321A for ; Wed, 3 Feb 2021 04:20:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A8B364F7E for ; Wed, 3 Feb 2021 04:20:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233056AbhBCET5 (ORCPT ); Tue, 2 Feb 2021 23:19:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36760 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232710AbhBCES1 (ORCPT ); Tue, 2 Feb 2021 23:18:27 -0500 Received: from mail-oi1-x234.google.com (mail-oi1-x234.google.com [IPv6:2607:f8b0:4864:20::234]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C7FBC0617A7; Tue, 2 Feb 2021 20:17:12 -0800 (PST) Received: by mail-oi1-x234.google.com with SMTP id a77so25393520oii.4; Tue, 02 Feb 2021 20:17:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=I8srG1L59T5lSA/sx67czDaMe/6mWiAIpF1LBobm/C8=; b=QUKYtXCfh0UBl/bdGnwunxOtACNvBs9dBnbmcTrJ7hHwRtG1ouO8NLCkYwNFQFZEbV f+dA61CT7JCiZ5+vin/uJGUccemujooRl2V4mA+RlpFTD79STZUetOqg7JfEO1chhVtf fpgIdQ2061t+NKr9r4ULHJDlWuFajw8OHMsoBhmXdB4Km7miTfaQ+A6lv8pXZow+dO96 Iy+BrDTXkOasf6fLNqvFBAdxAUqKj8AMiWrkTi0GWHoHATGApXWWrEY9dU1f557FFh34 mBv4uLZDx2MFjexS4w3vj2VyVkJ7sOz9GM3QuIXPyxKgj9Eu8jphlUBtU70ZOOgMZtkt KNVw== 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:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=I8srG1L59T5lSA/sx67czDaMe/6mWiAIpF1LBobm/C8=; b=hvLCRIALYAolPRld7L7Mw41a34fb2+pL3AGeqW3jW5H7eEoyYpG7qfCI5JQnAXu0pb /XQiUr2a3Vff6oHfNG55+6LIEa5TdFuloyNwtMFCBwRjkvnkCys2/UpKfs7uORGR7HAX cd7XUCcQ/GWX4N1mPCH4q6tUM+f2C8IqFnZSV8MUrVD/uoQKE+de41gfi6s8bEdvm3/U sQt7KCAhRTHOxS5NEZFSuYBrS2BnwwXMUito0Aijcf6u9+BLQx3MvTXuq0jcF/+HKMm4 M4LYH7zlD6o1w6M736P4U1DPjlS564P78CZ0b8MzdBW5irESXD+MaIJVCRS63PhvB1NC afAw== X-Gm-Message-State: AOAM530chb8QVZeuR23YREAe44yfxC1RyuaBWRtw77io0JamxW6IP14W 6FOGPu4yHyzj3g6aRbDRiBf094I+nKYabg== X-Google-Smtp-Source: ABdhPJzoP42CF4cWCYXDjP5S2b6u//MVgpOumSRK4FCz9fDlVcwcEbpF3oUWOBe/5hgwt29qVBW7+Q== X-Received: by 2002:aca:b683:: with SMTP id g125mr789725oif.47.1612325831586; Tue, 02 Feb 2021 20:17:11 -0800 (PST) Received: from unknown.attlocal.net ([2600:1700:65a0:ab60:90c4:ffea:6079:8a0c]) by smtp.gmail.com with ESMTPSA id s10sm209978ool.35.2021.02.02.20.17.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 Feb 2021 20:17:10 -0800 (PST) From: Cong Wang To: netdev@vger.kernel.org Cc: bpf@vger.kernel.org, duanxiongchun@bytedance.com, wangdongdong.6@bytedance.com, jiang.wang@bytedance.com, Cong Wang , John Fastabend , Daniel Borkmann , Jakub Sitnicki , Lorenz Bauer Subject: [Patch bpf-next 12/19] af_unix: implement ->update_proto() Date: Tue, 2 Feb 2021 20:16:29 -0800 Message-Id: <20210203041636.38555-13-xiyou.wangcong@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210203041636.38555-1-xiyou.wangcong@gmail.com> References: <20210203041636.38555-1-xiyou.wangcong@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net From: Cong Wang unix_proto is special, it is very different from INET proto, which even does not have a ->close(). We have to add a dummy one to satisfy sockmap. Cc: John Fastabend Cc: Daniel Borkmann Cc: Jakub Sitnicki Cc: Lorenz Bauer Signed-off-by: Cong Wang --- MAINTAINERS | 1 + include/net/af_unix.h | 10 +++++++++ net/unix/Makefile | 1 + net/unix/af_unix.c | 12 ++++++++++- net/unix/unix_bpf.c | 50 +++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 73 insertions(+), 1 deletion(-) create mode 100644 net/unix/unix_bpf.c diff --git a/MAINTAINERS b/MAINTAINERS index 1df56a32d2df..1fa3971c45b0 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9950,6 +9950,7 @@ F: net/core/skmsg.c F: net/core/sock_map.c F: net/ipv4/tcp_bpf.c F: net/ipv4/udp_bpf.c +F: net/unix/unix_bpf.c LANTIQ / INTEL Ethernet drivers M: Hauke Mehrtens diff --git a/include/net/af_unix.h b/include/net/af_unix.h index f42fdddecd41..fa75f899e88a 100644 --- a/include/net/af_unix.h +++ b/include/net/af_unix.h @@ -89,4 +89,14 @@ void unix_sysctl_unregister(struct net *net); static inline int unix_sysctl_register(struct net *net) { return 0; } static inline void unix_sysctl_unregister(struct net *net) {} #endif + +extern struct proto unix_proto; + +#ifdef CONFIG_BPF_SOCK_MAP +int unix_bpf_update_proto(struct sock *sk, bool restore); +void __init unix_bpf_build_proto(void); +#else +static inline void __init unix_bpf_build_proto(void) +{} +#endif #endif diff --git a/net/unix/Makefile b/net/unix/Makefile index 54e58cc4f945..7d2c70c575b6 100644 --- a/net/unix/Makefile +++ b/net/unix/Makefile @@ -7,6 +7,7 @@ obj-$(CONFIG_UNIX) += unix.o unix-y := af_unix.o garbage.o unix-$(CONFIG_SYSCTL) += sysctl_net_unix.o +unix-$(CONFIG_BPF_SOCK_MAP) += unix_bpf.o obj-$(CONFIG_UNIX_DIAG) += unix_diag.o unix_diag-y := diag.o diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index 9315c4f4c27a..4ce12d3c369e 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -773,10 +773,18 @@ static const struct proto_ops unix_seqpacket_ops = { .show_fdinfo = unix_show_fdinfo, }; -static struct proto unix_proto = { +static void unix_close(struct sock *sk, long timeout) +{ +} + +struct proto unix_proto = { .name = "UNIX", .owner = THIS_MODULE, .obj_size = sizeof(struct unix_sock), + .close = unix_close, +#ifdef CONFIG_BPF_SOCK_MAP + .update_proto = unix_bpf_update_proto, +#endif }; static struct sock *unix_create1(struct net *net, struct socket *sock, int kern) @@ -861,6 +869,7 @@ static int unix_release(struct socket *sock) return 0; unix_release_sock(sk, 0); + sk->sk_prot->close(sk, 0); sock->sk = NULL; return 0; @@ -2973,6 +2982,7 @@ static int __init af_unix_init(void) sock_register(&unix_family_ops); register_pernet_subsys(&unix_net_ops); + unix_bpf_build_proto(); out: return rc; } diff --git a/net/unix/unix_bpf.c b/net/unix/unix_bpf.c new file mode 100644 index 000000000000..2e6a26ec4958 --- /dev/null +++ b/net/unix/unix_bpf.c @@ -0,0 +1,50 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Cong Wang */ + +#include +#include +#include + +static struct proto *unix_prot_saved __read_mostly; +static DEFINE_SPINLOCK(unix_prot_lock); +static struct proto unix_bpf_prot; + +static void unix_bpf_rebuild_protos(struct proto *prot, const struct proto *base) +{ + *prot = *base; + prot->close = sock_map_close; +} + +static void unix_bpf_check_needs_rebuild(struct proto *ops) +{ + if (unlikely(ops != smp_load_acquire(&unix_prot_saved))) { + spin_lock_bh(&unix_prot_lock); + if (likely(ops != unix_prot_saved)) { + unix_bpf_rebuild_protos(&unix_bpf_prot, ops); + smp_store_release(&unix_prot_saved, ops); + } + spin_unlock_bh(&unix_prot_lock); + } +} + +int unix_bpf_update_proto(struct sock *sk, bool restore) +{ + struct sk_psock *psock = sk_psock(sk); + + if (restore) { + sk->sk_write_space = psock->saved_write_space; + /* Pairs with lockless read in sk_clone_lock() */ + WRITE_ONCE(sk->sk_prot, psock->sk_proto); + return 0; + } + + unix_bpf_check_needs_rebuild(psock->sk_proto); + /* Pairs with lockless read in sk_clone_lock() */ + WRITE_ONCE(sk->sk_prot, &unix_bpf_prot); + return 0; +} + +void __init unix_bpf_build_proto(void) +{ + unix_bpf_rebuild_protos(&unix_bpf_prot, &unix_proto); +}