From patchwork Tue Sep 18 16:01:44 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Fastabend X-Patchwork-Id: 971181 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=gmail.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42F76B0Nfdz9sBJ for ; Wed, 19 Sep 2018 02:01:54 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729964AbeIRVfB (ORCPT ); Tue, 18 Sep 2018 17:35:01 -0400 Received: from [184.63.162.180] ([184.63.162.180]:38096 "EHLO john-Precision-Tower-5810" rhost-flags-FAIL-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1729447AbeIRVfB (ORCPT ); Tue, 18 Sep 2018 17:35:01 -0400 Received: from [127.0.1.1] (localhost [127.0.0.1]) by john-Precision-Tower-5810 (Postfix) with ESMTP id 7BE5AD47662; Tue, 18 Sep 2018 09:01:44 -0700 (PDT) Subject: [bpf PATCH v4 1/3] bpf: sockmap only allow ESTABLISHED sock state From: John Fastabend To: edumazet@google.com, ast@kernel.org, daniel@iogearbox.net Cc: netdev@vger.kernel.org Date: Tue, 18 Sep 2018 09:01:44 -0700 Message-ID: <20180918160144.22728.72921.stgit@john-Precision-Tower-5810> In-Reply-To: <20180918155826.22728.71788.stgit@john-Precision-Tower-5810> References: <20180918155826.22728.71788.stgit@john-Precision-Tower-5810> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org After this patch we only allow socks that are in ESTABLISHED state or are being added via a sock_ops event that is transitioning into an ESTABLISHED state. By allowing sock_ops events we allow users to manage sockmaps directly from sock ops programs. The two supported sock_ops ops are BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB and BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB. Similar to TLS ULP this ensures sk_user_data is correct. Reported-by: Eric Dumazet Fixes: 1aa12bdf1bfb ("bpf: sockmap, add sock close() hook to remove socks") Signed-off-by: John Fastabend Acked-by: Yonghong Song --- kernel/bpf/sockmap.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index 488ef96..1f97b55 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -2097,8 +2097,12 @@ static int sock_map_update_elem(struct bpf_map *map, return -EINVAL; } + /* ULPs are currently supported only for TCP sockets in ESTABLISHED + * state. + */ if (skops.sk->sk_type != SOCK_STREAM || - skops.sk->sk_protocol != IPPROTO_TCP) { + skops.sk->sk_protocol != IPPROTO_TCP || + skops.sk->sk_state != TCP_ESTABLISHED) { fput(socket->file); return -EOPNOTSUPP; } @@ -2453,6 +2457,16 @@ static int sock_hash_update_elem(struct bpf_map *map, return -EINVAL; } + /* ULPs are currently supported only for TCP sockets in ESTABLISHED + * state. + */ + if (skops.sk->sk_type != SOCK_STREAM || + skops.sk->sk_protocol != IPPROTO_TCP || + skops.sk->sk_state != TCP_ESTABLISHED) { + fput(socket->file); + return -EOPNOTSUPP; + } + lock_sock(skops.sk); preempt_disable(); rcu_read_lock(); @@ -2543,10 +2557,22 @@ struct sock *__sock_hash_lookup_elem(struct bpf_map *map, void *key) .map_check_btf = map_check_no_btf, }; +static bool bpf_is_valid_sock_op(struct bpf_sock_ops_kern *ops) +{ + return ops->op == BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB || + ops->op == BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB; +} BPF_CALL_4(bpf_sock_map_update, struct bpf_sock_ops_kern *, bpf_sock, struct bpf_map *, map, void *, key, u64, flags) { WARN_ON_ONCE(!rcu_read_lock_held()); + + /* ULPs are currently supported only for TCP sockets in ESTABLISHED + * state. This checks that the sock ops triggering the update is + * one indicating we are (or will be soon) in an ESTABLISHED state. + */ + if (!bpf_is_valid_sock_op(bpf_sock)) + return -EOPNOTSUPP; return sock_map_ctx_update_elem(bpf_sock, map, key, flags); } @@ -2565,6 +2591,9 @@ struct sock *__sock_hash_lookup_elem(struct bpf_map *map, void *key) struct bpf_map *, map, void *, key, u64, flags) { WARN_ON_ONCE(!rcu_read_lock_held()); + + if (!bpf_is_valid_sock_op(bpf_sock)) + return -EOPNOTSUPP; return sock_hash_ctx_update_elem(bpf_sock, map, key, flags); }