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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 B0140C433E0 for ; Mon, 1 Jun 2020 18:42:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 87AD1206A4 for ; Mon, 1 Jun 2020 18:42:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591036923; bh=eb70qoh+OfrO/rHwsvzv7fHkdcQRk9oZcbVN3cI3xLU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ehrvY5FF1o7fcpRDtopDbj2NcGaILUAXxh5cTdbAfE5f/J+4F1G7XjL10JTHHgviR ipH3TXcVbcRxOF1UUSrDJsTqkhuCHeEHM2lxtalxQtS6+FFncz1NWZdwCkkH+2F/r+ TvDR9KYiCNeH3N2MoJeTYx/RClld5U2nTBLI9d5A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730773AbgFASMJ (ORCPT ); Mon, 1 Jun 2020 14:12:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:59480 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730764AbgFASMI (ORCPT ); Mon, 1 Jun 2020 14:12:08 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3844C20776; Mon, 1 Jun 2020 18:12:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591035127; bh=eb70qoh+OfrO/rHwsvzv7fHkdcQRk9oZcbVN3cI3xLU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WdUvm0YY5ISePaxwztdAoxGCqrigUQ+lYJiDveaZJs1NARRsEkMQZUsgYWhClm+5G n4cJwAiPcVrJFQGUV1U969Cp1A5qfdd/vVMN6AxTaTc2Re+tu/LrxuKGNwoHrftxUb vvSaAlZMz7rqNsh0EOwtuuHP4SMnK43gGmE/DInM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Jere=20Lepp=C3=A4nen?= , Marcelo Ricardo Leitner , "David S. Miller" Subject: [PATCH 5.6 021/177] sctp: Start shutdown on association restart if in SHUTDOWN-SENT state and socket is closed Date: Mon, 1 Jun 2020 19:52:39 +0200 Message-Id: <20200601174050.479844476@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200601174048.468952319@linuxfoundation.org> References: <20200601174048.468952319@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: "Jere Leppänen" [ Upstream commit d3e8e4c11870413789f029a71e72ae6e971fe678 ] Commit bdf6fa52f01b ("sctp: handle association restarts when the socket is closed.") starts shutdown when an association is restarted, if in SHUTDOWN-PENDING state and the socket is closed. However, the rationale stated in that commit applies also when in SHUTDOWN-SENT state - we don't want to move an association to ESTABLISHED state when the socket has been closed, because that results in an association that is unreachable from user space. The problem scenario: 1. Client crashes and/or restarts. 2. Server (using one-to-one socket) calls close(). SHUTDOWN is lost. 3. Client reconnects using the same addresses and ports. 4. Server's association is restarted. The association and the socket move to ESTABLISHED state, even though the server process has closed its descriptor. Also, after step 4 when the server process exits, some resources are leaked in an attempt to release the underlying inet sock structure in ESTABLISHED state: IPv4: Attempt to release TCP socket in state 1 00000000377288c7 Fix by acting the same way as in SHUTDOWN-PENDING state. That is, if an association is restarted in SHUTDOWN-SENT state and the socket is closed, then start shutdown and don't move the association or the socket to ESTABLISHED state. Fixes: bdf6fa52f01b ("sctp: handle association restarts when the socket is closed.") Signed-off-by: Jere Leppänen Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sctp/sm_statefuns.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -1856,12 +1856,13 @@ static enum sctp_disposition sctp_sf_do_ /* Update the content of current association. */ sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); - if (sctp_state(asoc, SHUTDOWN_PENDING) && + if ((sctp_state(asoc, SHUTDOWN_PENDING) || + sctp_state(asoc, SHUTDOWN_SENT)) && (sctp_sstate(asoc->base.sk, CLOSING) || sock_flag(asoc->base.sk, SOCK_DEAD))) { - /* if were currently in SHUTDOWN_PENDING, but the socket - * has been closed by user, don't transition to ESTABLISHED. - * Instead trigger SHUTDOWN bundled with COOKIE_ACK. + /* If the socket has been closed by user, don't + * transition to ESTABLISHED. Instead trigger SHUTDOWN + * bundled with COOKIE_ACK. */ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); return sctp_sf_do_9_2_start_shutdown(net, ep, asoc,