From nobody Thu Feb 12 11:16:34 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 313A6C2BA16 for ; Sat, 16 Sep 2023 10:54:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239167AbjIPKy3 (ORCPT ); Sat, 16 Sep 2023 06:54:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239113AbjIPKyF (ORCPT ); Sat, 16 Sep 2023 06:54:05 -0400 Received: from mail-wm1-x32b.google.com (mail-wm1-x32b.google.com [IPv6:2a00:1450:4864:20::32b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E52DCF9 for ; Sat, 16 Sep 2023 03:53:59 -0700 (PDT) Received: by mail-wm1-x32b.google.com with SMTP id 5b1f17b1804b1-404c023ef5eso10195735e9.2 for ; Sat, 16 Sep 2023 03:53:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tessares.net; s=google; t=1694861638; x=1695466438; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=WOY/sqAjV4zUSxnEWz+4l2rDatIUvlvXWdj0HM6CCVY=; b=PKfu4iffbjVERDVY2Vcn8VcyF8CsCSvkuBBgSddX7Ont/NjfboopDakF9Eq8WJJPxf fF9MtQVi4eJbFVwhIaPRF9SCTR/+iGs3/bHyovlQ3jAMkj3yajlBAdKWM9D6+u1ciM8K fzSzjWcdrVsGShblgTBhg/Qze3hNDtAXIFy41rGskj5ZGBH1xbbIVCPnu4ikxX5FKyJP 5SUPj0wcr6E93OC2Ze3a043R9zlohCyHybp83XblAmFpBuL84tz7QBrFElbfCcFr4xj6 sklNQz+UUodGb66YB6FP44Pd+9hysG3jEv3+dV0l3qkkldYR4tFwkjmW1u/ZeisyNj5a bQpw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694861638; x=1695466438; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=WOY/sqAjV4zUSxnEWz+4l2rDatIUvlvXWdj0HM6CCVY=; b=WEpVvhoFuJUWjFl5NPH+S9xgJOFXDQokhTFtG1jP9cVwmh1GP7mRf9ymQMKx85gGCu 2+kGGJwkLTdPVyiqQcfveggTZf6KQZawWNao4agVXxwLlQU6MJl0ZSSUcFE4Cmy3sthu pJBxeNHyW0gmwc/cY7ybthC8f6mx3fSvl0hpmPs07uozWrXHG8KZwVDzyMx6oL1cAEhh iX6/hDNatTL0mxzy/wvh+/KQxOB+28rQyjFPN3md07OJ+xNmN+4gwMGjwwh//cr2kzTf /jiwHKaxHA5bMUZpeNfkEEFtq6k8rdFNWa46hhy17GIDt1fexc8umW8auHSLmpcg9/Ar r0EQ== X-Gm-Message-State: AOJu0YxYjKhSL9BkgU7NkG7HIltDlq6iZWm7TDAykyiHHLy+HO+l66eW 5DxnRfRy1EKYPe2GMVl3fu+UlQ== X-Google-Smtp-Source: AGHT+IHdx6+03wALwlLa6aUnQuHEThxyzxSQi4wfPfRJ+Tc+CdiQk+bMgxnb4LTTDDWLjxZJL/mjZw== X-Received: by 2002:a05:600c:1d1d:b0:404:fc51:4e9f with SMTP id l29-20020a05600c1d1d00b00404fc514e9fmr848227wms.38.1694861637487; Sat, 16 Sep 2023 03:53:57 -0700 (PDT) Received: from vdi08.nix.tessares.net (static.219.156.76.144.clients.your-server.de. [144.76.156.219]) by smtp.gmail.com with ESMTPSA id z20-20020a7bc7d4000000b003feae747ff2sm9900743wmk.35.2023.09.16.03.53.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 16 Sep 2023 03:53:57 -0700 (PDT) From: Matthieu Baerts Date: Sat, 16 Sep 2023 12:52:47 +0200 Subject: [PATCH net 3/5] mptcp: process pending subflow error on close MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20230916-upstream-net-20230915-mptcp-hanging-conn-v1-3-05d1a8b851a8@tessares.net> References: <20230916-upstream-net-20230915-mptcp-hanging-conn-v1-0-05d1a8b851a8@tessares.net> In-Reply-To: <20230916-upstream-net-20230915-mptcp-hanging-conn-v1-0-05d1a8b851a8@tessares.net> To: mptcp@lists.linux.dev, Mat Martineau , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Davide Caratti Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Matthieu Baerts , stable@vger.kernel.org X-Mailer: b4 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=3415; i=matthieu.baerts@tessares.net; h=from:subject:message-id; bh=rdxdMoVy0CrsijRyr+7AHTMv9lxPX17lbBfXAdrgKyY=; b=owEBbQKS/ZANAwAIAfa3gk9CaaBzAcsmYgBlBYlA/V7jp2UdAR1ummQors/RC6sQbjMGfs6Ah 9bxgcKzDFiJAjMEAAEIAB0WIQToy4X3aHcFem4n93r2t4JPQmmgcwUCZQWJQAAKCRD2t4JPQmmg c+c/D/9DecyoVShlh2Qpntbg0GirJyOPYGcTM8Y85bP1kAbH49a4djc1lUD6FDQdyF8QINSHTA0 sWQtPzk0yOBhkSbL3rLgikx9q+1MjeHi9V0ElbBxracI4l6yXOZ8Aq/O0wX6bJi69904DEHaC93 mFzPS3wtpskCrFb/I8NCI9s4fKJV5gWNGt2KTnaadwb715HWfDw+5Yh92UIBGCQH8eQ0ppIX0+o 9HZ0VWGCIKKuw5emi2U0vfuAo5ktvZYKU0s2I89cWiLKVeuN/N0mcPJX6pgFUXyHTBSqgWPz248 arQoGazScqsAoLB85T6hSKpqbdGCsnluQO7hfFQutjrLJjecueJF/a9Gm2lleffo8flxW+V42Ok 0+dM9xqz3ITO/Gv4sn8OjWJrDFTW/FixA11fS055ToJQrCN+DOH568jea5b/7tkLDkVWMcjCIF/ TFns2aAM9vnhz8fra7WBmhOgCMdzqBJrzPftx05oBZV6W0zfHUWl/nSQKTrTkvS1CfKt9/wdbqm r2/lJn0RR2Y5D82x1CJCT2WomPziMIenQy2kifaVdUBKKceu0Om4ASAOQ8RcRJYcia3zwH4d2bh moYYKYQDNONipi606AkhMYUaF+XPNak+s/orNRz7229Uum19JAFLU3XL5dOyQkwEGtzeUyNn1fY 9nRzpJUse4ogShQ== X-Developer-Key: i=matthieu.baerts@tessares.net; a=openpgp; fpr=E8CB85F76877057A6E27F77AF6B7824F4269A073 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Paolo Abeni On incoming TCP reset, subflow closing could happen before error propagation. That in turn could cause the socket error being ignored, and a missing socket state transition, as reported by Daire-Byrne. Address the issues explicitly checking for subflow socket error at close time. To avoid code duplication, factor-out of __mptcp_error_report() a new helper implementing the relevant bits. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/429 Fixes: 15cc10453398 ("mptcp: deliver ssk errors to msk") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni Reviewed-by: Mat Martineau Signed-off-by: Matthieu Baerts --- net/mptcp/protocol.c | 63 ++++++++++++++++++++++++++++--------------------= ---- 1 file changed, 34 insertions(+), 29 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 915860027b1a..1c96b8da71df 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -770,40 +770,44 @@ static bool __mptcp_ofo_queue(struct mptcp_sock *msk) return moved; } =20 +static bool __mptcp_subflow_error_report(struct sock *sk, struct sock *ssk) +{ + int err =3D sock_error(ssk); + int ssk_state; + + if (!err) + return false; + + /* only propagate errors on fallen-back sockets or + * on MPC connect + */ + if (sk->sk_state !=3D TCP_SYN_SENT && !__mptcp_check_fallback(mptcp_sk(sk= ))) + return false; + + /* We need to propagate only transition to CLOSE state. + * Orphaned socket will see such state change via + * subflow_sched_work_if_closed() and that path will properly + * destroy the msk as needed. + */ + ssk_state =3D inet_sk_state_load(ssk); + if (ssk_state =3D=3D TCP_CLOSE && !sock_flag(sk, SOCK_DEAD)) + inet_sk_state_store(sk, ssk_state); + WRITE_ONCE(sk->sk_err, -err); + + /* This barrier is coupled with smp_rmb() in mptcp_poll() */ + smp_wmb(); + sk_error_report(sk); + return true; +} + void __mptcp_error_report(struct sock *sk) { struct mptcp_subflow_context *subflow; struct mptcp_sock *msk =3D mptcp_sk(sk); =20 - mptcp_for_each_subflow(msk, subflow) { - struct sock *ssk =3D mptcp_subflow_tcp_sock(subflow); - int err =3D sock_error(ssk); - int ssk_state; - - if (!err) - continue; - - /* only propagate errors on fallen-back sockets or - * on MPC connect - */ - if (sk->sk_state !=3D TCP_SYN_SENT && !__mptcp_check_fallback(msk)) - continue; - - /* We need to propagate only transition to CLOSE state. - * Orphaned socket will see such state change via - * subflow_sched_work_if_closed() and that path will properly - * destroy the msk as needed. - */ - ssk_state =3D inet_sk_state_load(ssk); - if (ssk_state =3D=3D TCP_CLOSE && !sock_flag(sk, SOCK_DEAD)) - inet_sk_state_store(sk, ssk_state); - WRITE_ONCE(sk->sk_err, -err); - - /* This barrier is coupled with smp_rmb() in mptcp_poll() */ - smp_wmb(); - sk_error_report(sk); - break; - } + mptcp_for_each_subflow(msk, subflow) + if (__mptcp_subflow_error_report(sk, mptcp_subflow_tcp_sock(subflow))) + break; } =20 /* In most cases we will be able to lock the mptcp socket. If its already @@ -2428,6 +2432,7 @@ static void __mptcp_close_ssk(struct sock *sk, struct= sock *ssk, } =20 out_release: + __mptcp_subflow_error_report(sk, ssk); release_sock(ssk); =20 sock_put(ssk); --=20 2.40.1