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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 346ABC2D0DB for ; Mon, 27 Jan 2020 12:55:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0C97F20842 for ; Mon, 27 Jan 2020 12:55:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=cloudflare.com header.i=@cloudflare.com header.b="k+g6lrCQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727067AbgA0Mzv (ORCPT ); Mon, 27 Jan 2020 07:55:51 -0500 Received: from mail-lj1-f196.google.com ([209.85.208.196]:44855 "EHLO mail-lj1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726210AbgA0Mzr (ORCPT ); Mon, 27 Jan 2020 07:55:47 -0500 Received: by mail-lj1-f196.google.com with SMTP id q8so10504350ljj.11 for ; Mon, 27 Jan 2020 04:55:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloudflare.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=FNMkWCVrDwSTMxAPnYhbyJcpefMCHVAH/UCnwzz9dvU=; b=k+g6lrCQmXlcIKPFzPdRTQttWUTokV+9T9feAiGcIjkEgtONj/z5JgS4292Y/irb6w ndcAgRS7yFzytm0IIx/AKi3wcUVBheKuyict8jeInT5S+flv9j0MCK63ovXadjIep1U4 m8wR/5pn4V9mr0lD9hMYn99jlCYWIwSSNVJV4= 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=FNMkWCVrDwSTMxAPnYhbyJcpefMCHVAH/UCnwzz9dvU=; b=muDTZo+fu14aTYWGXVDTTl6aVxPtAxr3XwN02VLQ2YU7Tm27J/ns4Oz9hSsQkp47XL vmq2Gtdkg4nPZTAD7bJMZD2kFM6iYH0O2Ir32bl/dO89pXhNVrVOdUXVIRf6AnE8FhZ7 Banybnd0dMFIAPz6CybMsM/grWlheeuJtNZv5dmiqYLcmGFyAAoemTtwteCYLeTWnljT Dsi9CIJo8YJUCRRxQCVX5lH++IbY5f47Mo4ERsfjxnXoBj8NLHOUS/YMmMISHO1queYE +g7jIgbRzE3B2G59sQuGnBvVs6nAsbr8BD+if8hUkWAxFG9eh3fwL3pH7BJebcIxcaCm zw3g== X-Gm-Message-State: APjAAAVUL7ik1r5xgNDOwHmHW+pHyZXgsaMtV96uv1Xe9O0nf50Pq5Rv jJ1lUvXJ7PAKk4yJ4rYNcbx2jVB+IUoy8A== X-Google-Smtp-Source: APXvYqwDa5J2qOCcMdiZTMyzGgpAPPvklrkLnoCzwFIBf5iDJ/PKHQ5FMnmkMNiHkq23oH63e74/FA== X-Received: by 2002:a2e:84d0:: with SMTP id q16mr10254251ljh.138.1580129744229; Mon, 27 Jan 2020 04:55:44 -0800 (PST) Received: from cloudflare.com ([2a02:a310:c262:aa00:b35e:8938:2c2a:ba8b]) by smtp.gmail.com with ESMTPSA id j7sm4306793ljg.25.2020.01.27.04.55.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Jan 2020 04:55:43 -0800 (PST) From: Jakub Sitnicki To: bpf@vger.kernel.org Cc: netdev@vger.kernel.org, kernel-team@cloudflare.com, Martin KaFai Lau Subject: [PATCH bpf-next v5 05/12] bpf, sockmap: Allow inserting listening TCP sockets into sockmap Date: Mon, 27 Jan 2020 13:55:27 +0100 Message-Id: <20200127125534.137492-6-jakub@cloudflare.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200127125534.137492-1-jakub@cloudflare.com> References: <20200127125534.137492-1-jakub@cloudflare.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org In order for sockmap type to become a generic collection for storing TCP sockets we need to loosen the checks during map update, while tightening the checks in redirect helpers. Currently sockmap requires the TCP socket to be in established state (or transitioning out of SYN_RECV into established state when done from BPF), which prevents inserting listening sockets. Change the update pre-checks so the socket can also be in listening state. Since it doesn't make sense to redirect with sockmap to listening sockets, add appropriate socket state checks to BPF redirect helpers too. We leave sockhash as is for the moment, with no support for holding listening sockets. Therefore sockhash needs its own set of checks. Acked-by: Martin KaFai Lau Signed-off-by: Jakub Sitnicki --- net/core/sock_map.c | 62 +++++++++++++++++++------ tools/testing/selftests/bpf/test_maps.c | 6 +-- 2 files changed, 50 insertions(+), 18 deletions(-) diff --git a/net/core/sock_map.c b/net/core/sock_map.c index 8998e356f423..954c4d23bc01 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -388,15 +388,44 @@ static int sock_map_update_common(struct bpf_map *map, u32 idx, } static bool sock_map_op_okay(const struct bpf_sock_ops_kern *ops) +{ + return ops->op == BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB || + ops->op == BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB || + ops->op == BPF_SOCK_OPS_TCP_LISTEN_CB; +} + +static bool sock_hash_op_okay(const struct bpf_sock_ops_kern *ops) { return ops->op == BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB || ops->op == BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB; } +/* Only TCP sockets can be inserted into the map. They must be either + * in established or listening state. SYN_RECV is also allowed because + * BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB happens just before socket + * enters established state. + */ static bool sock_map_sk_is_suitable(const struct sock *sk) { return sk->sk_type == SOCK_STREAM && - sk->sk_protocol == IPPROTO_TCP; + sk->sk_protocol == IPPROTO_TCP && + (1 << sk->sk_state) & (TCPF_ESTABLISHED | + TCPF_SYN_RECV | + TCPF_LISTEN); +} + +static bool sock_hash_sk_is_suitable(const struct sock *sk) +{ + return sk->sk_type == SOCK_STREAM && + sk->sk_protocol == IPPROTO_TCP && + (1 << sk->sk_state) & (TCPF_ESTABLISHED | + TCPF_SYN_RECV); +} + +/* Is sock in a state that allows redirecting into it? */ +static bool sock_map_redirect_okay(const struct sock *sk) +{ + return sk->sk_state != TCP_LISTEN; } static int sock_map_update_elem(struct bpf_map *map, void *key, @@ -416,8 +445,7 @@ static int sock_map_update_elem(struct bpf_map *map, void *key, ret = -EINVAL; goto out; } - if (!sock_map_sk_is_suitable(sk) || - sk->sk_state != TCP_ESTABLISHED) { + if (!sock_map_sk_is_suitable(sk)) { ret = -EOPNOTSUPP; goto out; } @@ -457,13 +485,17 @@ BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb, struct bpf_map *, map, u32, key, u64, flags) { struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); + struct sock *sk; if (unlikely(flags & ~(BPF_F_INGRESS))) return SK_DROP; - tcb->bpf.flags = flags; - tcb->bpf.sk_redir = __sock_map_lookup_elem(map, key); - if (!tcb->bpf.sk_redir) + + sk = __sock_map_lookup_elem(map, key); + if (unlikely(!sk || !sock_map_redirect_okay(sk))) return SK_DROP; + + tcb->bpf.flags = flags; + tcb->bpf.sk_redir = sk; return SK_PASS; } @@ -480,12 +512,17 @@ const struct bpf_func_proto bpf_sk_redirect_map_proto = { BPF_CALL_4(bpf_msg_redirect_map, struct sk_msg *, msg, struct bpf_map *, map, u32, key, u64, flags) { + struct sock *sk; + if (unlikely(flags & ~(BPF_F_INGRESS))) return SK_DROP; - msg->flags = flags; - msg->sk_redir = __sock_map_lookup_elem(map, key); - if (!msg->sk_redir) + + sk = __sock_map_lookup_elem(map, key); + if (unlikely(!sk || !sock_map_redirect_okay(sk))) return SK_DROP; + + msg->flags = flags; + msg->sk_redir = sk; return SK_PASS; } @@ -739,8 +776,7 @@ static int sock_hash_update_elem(struct bpf_map *map, void *key, ret = -EINVAL; goto out; } - if (!sock_map_sk_is_suitable(sk) || - sk->sk_state != TCP_ESTABLISHED) { + if (!sock_hash_sk_is_suitable(sk)) { ret = -EOPNOTSUPP; goto out; } @@ -887,8 +923,8 @@ BPF_CALL_4(bpf_sock_hash_update, struct bpf_sock_ops_kern *, sops, { WARN_ON_ONCE(!rcu_read_lock_held()); - if (likely(sock_map_sk_is_suitable(sops->sk) && - sock_map_op_okay(sops))) + if (likely(sock_hash_sk_is_suitable(sops->sk) && + sock_hash_op_okay(sops))) return sock_hash_update_common(map, key, sops->sk, flags); return -EOPNOTSUPP; } diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c index 02eae1e864c2..c6766b2cff85 100644 --- a/tools/testing/selftests/bpf/test_maps.c +++ b/tools/testing/selftests/bpf/test_maps.c @@ -756,11 +756,7 @@ static void test_sockmap(unsigned int tasks, void *data) /* Test update without programs */ for (i = 0; i < 6; i++) { err = bpf_map_update_elem(fd, &i, &sfd[i], BPF_ANY); - if (i < 2 && !err) { - printf("Allowed update sockmap '%i:%i' not in ESTABLISHED\n", - i, sfd[i]); - goto out_sockmap; - } else if (i >= 2 && err) { + if (err) { printf("Failed noprog update sockmap '%i:%i'\n", i, sfd[i]); goto out_sockmap; -- 2.24.1