From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:47766 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727605AbeJSCAG (ORCPT ); Thu, 18 Oct 2018 22:00:06 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , John Fastabend , Yonghong Song , Daniel Borkmann , Sasha Levin Subject: [PATCH 4.18 36/53] bpf: sockmap only allow ESTABLISHED sock state Date: Thu, 18 Oct 2018 19:54:29 +0200 Message-Id: <20181018175422.888783173@linuxfoundation.org> In-Reply-To: <20181018175416.561567978@linuxfoundation.org> References: <20181018175416.561567978@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: John Fastabend [ Upstream commit 5607fff303636d48b88414c6be353d9fed700af2 ] 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 Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- kernel/bpf/sockmap.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -2100,8 +2100,12 @@ static int sock_map_update_elem(struct b 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; } @@ -2456,6 +2460,16 @@ static int sock_hash_update_elem(struct 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(); @@ -2544,10 +2558,22 @@ const struct bpf_map_ops sock_hash_ops = .map_release_uref = sock_map_release, }; +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); } @@ -2566,6 +2592,9 @@ BPF_CALL_4(bpf_sock_hash_update, struct 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); }