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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 DE725C43381 for ; Fri, 22 Mar 2019 11:34:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AF3EC21929 for ; Fri, 22 Mar 2019 11:34:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553254459; bh=JXSHeJ9YY4t8zr67PU0dgb4Ny2AIW3b5mPYbX2RaiTc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ykxdS5jiKqK//zB1HLgqYTnjlEcbTklc0i1eOVwMCmF5MIkK7P5ZNk+8l/T4O6aja wjV1q3Y8mR/W4UZ7Ds1cJxPSvW+kIsbEqk88Y13Wo3fR5x5o58A2XPVmgEwnooqWPi lRD3YbeUCO74lSVNmq5RxhZ4H2vtwi6jlaGFK96g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730397AbfCVLeS (ORCPT ); Fri, 22 Mar 2019 07:34:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:34884 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729680AbfCVLeP (ORCPT ); Fri, 22 Mar 2019 07:34:15 -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 396422192C; Fri, 22 Mar 2019 11:34:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553254454; bh=JXSHeJ9YY4t8zr67PU0dgb4Ny2AIW3b5mPYbX2RaiTc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Wp0FoZloqTbzWJfVp20+HAg33oLscBim758C2nK01jgHl1bELKFS1UIZ8R5Kao/xg yuFU5XS2uil58WKbnz8rESUDHOLWQldagy7QCjvHU+UeRdI7u0Psqiu8vtsCd1wXYN b0py+3fofP+cIViPDf1GxuK1A5ndE9Jpk/cM341M= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Guillaume Nault , Eric Dumazet , "David S. Miller" Subject: [PATCH 4.4 133/230] tcp: handle inet_csk_reqsk_queue_add() failures Date: Fri, 22 Mar 2019 12:14:31 +0100 Message-Id: <20190322111246.021116010@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190322111236.796964179@linuxfoundation.org> References: <20190322111236.796964179@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Guillaume Nault [ Upstream commit 9d3e1368bb45893a75a5dfb7cd21fdebfa6b47af ] Commit 7716682cc58e ("tcp/dccp: fix another race at listener dismantle") let inet_csk_reqsk_queue_add() fail, and adjusted {tcp,dccp}_check_req() accordingly. However, TFO and syncookies weren't modified, thus leaking allocated resources on error. Contrary to tcp_check_req(), in both syncookies and TFO cases, we need to drop the request socket. Also, since the child socket is created with inet_csk_clone_lock(), we have to unlock it and drop an extra reference (->sk_refcount is initially set to 2 and inet_csk_reqsk_queue_add() drops only one ref). For TFO, we also need to revert the work done by tcp_try_fastopen() (with reqsk_fastopen_remove()). Fixes: 7716682cc58e ("tcp/dccp: fix another race at listener dismantle") Signed-off-by: Guillaume Nault Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/syncookies.c | 7 ++++++- net/ipv4/tcp_input.c | 8 +++++++- 2 files changed, 13 insertions(+), 2 deletions(-) --- a/net/ipv4/syncookies.c +++ b/net/ipv4/syncookies.c @@ -228,7 +228,12 @@ struct sock *tcp_get_cookie_sock(struct if (child) { atomic_set(&req->rsk_refcnt, 1); sock_rps_save_rxhash(child, skb); - inet_csk_reqsk_queue_add(sk, req, child); + if (!inet_csk_reqsk_queue_add(sk, req, child)) { + bh_unlock_sock(child); + sock_put(child); + child = NULL; + reqsk_put(req); + } } else { reqsk_free(req); } --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -6409,7 +6409,13 @@ int tcp_conn_request(struct request_sock af_ops->send_synack(fastopen_sk, dst, &fl, req, &foc, false); /* Add the child socket directly into the accept queue */ - inet_csk_reqsk_queue_add(sk, req, fastopen_sk); + if (!inet_csk_reqsk_queue_add(sk, req, fastopen_sk)) { + reqsk_fastopen_remove(fastopen_sk, req, false); + bh_unlock_sock(fastopen_sk); + sock_put(fastopen_sk); + reqsk_put(req); + goto drop; + } sk->sk_data_ready(sk); bh_unlock_sock(fastopen_sk); sock_put(fastopen_sk);