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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 7D501C33CA2 for ; Wed, 8 Jan 2020 17:03:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5D47A20692 for ; Wed, 8 Jan 2020 17:03:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729586AbgAHRDB (ORCPT ); Wed, 8 Jan 2020 12:03:01 -0500 Received: from www62.your-server.de ([213.133.104.62]:38434 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729516AbgAHRDB (ORCPT ); Wed, 8 Jan 2020 12:03:01 -0500 Received: from [2001:1620:665:0:5795:5b0a:e5d5:5944] (helo=localhost) by www62.your-server.de with esmtpsa (TLSv1.2:DHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89_1) (envelope-from ) id 1ipEjU-0001Cc-8d; Wed, 08 Jan 2020 18:03:00 +0100 Date: Wed, 8 Jan 2020 18:02:59 +0100 From: Daniel Borkmann To: Lingpeng Chen Cc: John Fastabend , netdev@vger.kernel.org, bpf@vger.kernel.org Subject: Re: [PATCH] bpf/sockmap: read psock ingress_msg before sk_receive_queue Message-ID: <20200108170259.GA7665@linux-3.fritz.box> References: <5e15526d2ebb6_68832ae93d7145c08c@john-XPS-13-9370.notmuch> <20200108045708.31240-1-forrest0579@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200108045708.31240-1-forrest0579@gmail.com> User-Agent: Mutt/1.12.1 (2019-06-15) X-Authenticated-Sender: daniel@iogearbox.net X-Virus-Scanned: Clear (ClamAV 0.101.4/25688/Wed Jan 8 10:56:24 2020) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, Jan 08, 2020 at 12:57:08PM +0800, Lingpeng Chen wrote: > Right now in tcp_bpf_recvmsg, sock read data first from sk_receive_queue > if not empty than psock->ingress_msg otherwise. If a FIN packet arrives > and there's also some data in psock->ingress_msg, the data in > psock->ingress_msg will be purged. It is always happen when request to a > HTTP1.0 server like python SimpleHTTPServer since the server send FIN > packet after data is sent out. > > Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") > Reported-by: Arika Chen > Suggested-by: Arika Chen > Signed-off-by: Lingpeng Chen > Signed-off-by: John Fastabend > --- > net/ipv4/tcp_bpf.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/net/ipv4/tcp_bpf.c b/net/ipv4/tcp_bpf.c > index e38705165ac9..f7e902868fce 100644 > --- a/net/ipv4/tcp_bpf.c > +++ b/net/ipv4/tcp_bpf.c > @@ -123,12 +123,13 @@ int tcp_bpf_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, > > if (unlikely(flags & MSG_ERRQUEUE)) > return inet_recv_error(sk, msg, len, addr_len); Shouldn't we also move the error queue handling below the psock test as well and let tcp_recvmsg() natively do it in case of !psock? > - if (!skb_queue_empty(&sk->sk_receive_queue)) > - return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len); > > psock = sk_psock_get(sk); > if (unlikely(!psock)) > return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len); > + if (!skb_queue_empty(&sk->sk_receive_queue) && > + sk_psock_queue_empty(psock)) > + return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len); > lock_sock(sk); > msg_bytes_ready: > copied = __tcp_bpf_recvmsg(sk, psock, msg, len, flags); > @@ -139,7 +140,7 @@ int tcp_bpf_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, > timeo = sock_rcvtimeo(sk, nonblock); > data = tcp_bpf_wait_data(sk, psock, flags, timeo, &err); > if (data) { > - if (skb_queue_empty(&sk->sk_receive_queue)) > + if (!sk_psock_queue_empty(psock)) > goto msg_bytes_ready; > release_sock(sk); > sk_psock_put(sk, psock); > -- > 2.17.1 >