From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C702D804 for ; Wed, 31 Aug 2022 10:48:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1661942882; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=MktVlESIxF5OksmKslWtqQ6KSEWRVt99UIzgxPjuTgc=; b=F64f9NIUn8Fsx//DQmn6VPYyvHVk1YA/YtvGTNMdJO7qMpfjCZSDQevfj080mjBYGESAkv WqRjsLQYdn+ImE75Wp6qskWPeJsRa/pMFrz18TUEjbQqS/pDeTIzZuNKsh4stGn1mWJD/7 Azy+3PQxtysou1PfqiAMbrgtTMrT4Jo= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-364-vBenvVuOMZ2JS5lPNlO7Rw-1; Wed, 31 Aug 2022 06:48:01 -0400 X-MC-Unique: vBenvVuOMZ2JS5lPNlO7Rw-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 20CB3185A7A4 for ; Wed, 31 Aug 2022 10:48:01 +0000 (UTC) Received: from gerbillo.redhat.com (unknown [10.39.193.59]) by smtp.corp.redhat.com (Postfix) with ESMTP id A2A5440CF8EE for ; Wed, 31 Aug 2022 10:48:00 +0000 (UTC) From: Paolo Abeni To: mptcp@lists.linux.dev Subject: [PATCH mptcp-next v2 1/2] mptcp: propagate fastclose error. Date: Wed, 31 Aug 2022 12:47:42 +0200 Message-Id: <5e26963328ae04aa375089a713ec40f5eb6adacd.1661942855.git.pabeni@redhat.com> Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.11.54.1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII"; x-default=true When an mptcp socket is closed due to an incoming FASTCLOSE option, so specific sk_err is set and later syscall will fail usually with EPIPE. Align the current fastclose error handling with TCP reset, properly setting the socket error according to the current msk state and propagating such error. Additionally sendmsg() is currently not handling properly the sk_err, always returning EPIPE. Signed-off-by: Paolo Abeni --- net/mptcp/protocol.c | 45 ++++++++++++++++++++++++++++++++++---------- 1 file changed, 35 insertions(+), 10 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index f4891db86217..b04f184695e4 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1685,9 +1685,13 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) { ret = sk_stream_wait_connect(sk, &timeo); if (ret) - goto out; + goto do_error; } + ret = -EPIPE; + if (unlikely(sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))) + goto do_error; + pfrag = sk_page_frag(sk); while (msg_data_left(msg)) { @@ -1696,11 +1700,6 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) bool dfrag_collapsed; size_t psize, offset; - if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) { - ret = -EPIPE; - goto out; - } - /* reuse tail pfrag, if possible, or carve a new one from the * page allocator */ @@ -1732,7 +1731,7 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) if (copy_page_from_iter(dfrag->page, offset, psize, &msg->msg_iter) != psize) { ret = -EFAULT; - goto out; + goto do_error; } /* data successfully copied into the write queue */ @@ -1764,7 +1763,7 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) __mptcp_push_pending(sk, msg->msg_flags); ret = sk_stream_wait_memory(sk, &timeo); if (ret) - goto out; + goto do_error; } if (copied) @@ -1772,7 +1771,14 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) out: release_sock(sk); - return copied ? : ret; + return copied; + +do_error: + if (copied) + goto out; + + copied = sk_stream_error(sk, msg->msg_flags, ret); + goto out; } static int __mptcp_recvmsg_mskq(struct mptcp_sock *msk, @@ -2404,12 +2410,31 @@ static void mptcp_check_fastclose(struct mptcp_sock *msk) unlock_sock_fast(tcp_sk, slow); } + /* Mirror the tcp_reset() error propagation */ + switch (sk->sk_state) { + case TCP_SYN_SENT: + sk->sk_err = ECONNREFUSED; + break; + case TCP_CLOSE_WAIT: + sk->sk_err = EPIPE; + break; + case TCP_CLOSE: + return; + default: + sk->sk_err = ECONNRESET; + } + inet_sk_state_store(sk, TCP_CLOSE); sk->sk_shutdown = SHUTDOWN_MASK; smp_mb__before_atomic(); /* SHUTDOWN must be visible first */ set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &msk->flags); - mptcp_close_wake_up(sk); + /* the calling mptcp_worker will properly destroy the socket */ + if (sock_flag(sk, SOCK_DEAD)) + return; + + sk->sk_state_change(sk); + sk_error_report(sk); } static void __mptcp_retrans(struct sock *sk) -- 2.37.2