From patchwork Wed Sep 2 14:05:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tim Froidcoeur X-Patchwork-Id: 264407 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=-13.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 5286BC433E7 for ; Wed, 2 Sep 2020 14:07:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E6D8207D3 for ; Wed, 2 Sep 2020 14:07:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=tessares-net.20150623.gappssmtp.com header.i=@tessares-net.20150623.gappssmtp.com header.b="DNH5Altg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727954AbgIBOHl (ORCPT ); Wed, 2 Sep 2020 10:07:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37006 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727931AbgIBOGP (ORCPT ); Wed, 2 Sep 2020 10:06:15 -0400 Received: from mail-ed1-x544.google.com (mail-ed1-x544.google.com [IPv6:2a00:1450:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2F2E9C06124F for ; Wed, 2 Sep 2020 07:05:39 -0700 (PDT) Received: by mail-ed1-x544.google.com with SMTP id a12so5030389eds.13 for ; Wed, 02 Sep 2020 07:05:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tessares-net.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=ms87tpPV92xBIrK+FIwRr75+U/FSoHz11mIuiBxrPvY=; b=DNH5AltgSY8a9qXUpBqw27brBXKQscc7pNvF5CWeZVI0Vgl0/fE7HqiUWPKXiw2VtB ZQ57MjmmwHbTeGIR6/0BLzFjS7wXwcF7TrjJjjUV1hNYGnEHz4eaYGGiwFaKfFSgaeoe 4cKBZBB9sE24DiD0f5VjoffAKhLzfOLMgPrEPDjxMX+M+0wPZ5G/gPoy4qBfULEPO9uY yrV0DWSQhqEuNfHXT8fyfMQ8/KOmooSAqNujpWcN2LcMW7x02Y8hVbYcJ229yTkXLVue xi3hDDv7FvrXzM7E3S7fKB3CkcymDqZ/IMyBd02et+w8rtI1if8qxZfFs0uJhyZOJjK9 dbCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ms87tpPV92xBIrK+FIwRr75+U/FSoHz11mIuiBxrPvY=; b=Qc12yEmVUT+j24V3izXhYAKnsRA3c8MSRknYm3zV0q37Tp5El8Y937Wpqgof9ClUex 4paznKQKkDTIp/KTNkAVwMqlaRsbgtHLugNZ9eywtCdTpV4OykNbFicI3W5AdxhcDIDI 0A8fWwpTffM5M0KgFHhoevYkh2RAOPN64FAT/M+4iga5F+zyyZygjzxt2VzI5cJ+9bGs Xo2tu2VnD56uPTeeEx9WBr/E8ilmlBG9RQZ07ms0KPEU8oYHkMoi8U+QoYvXacqern93 QhMXU5Yw1w6GiWCMZ4oqz8juVbCMtbXg0J1mLiz9uZMbjXzgUTSfor4s5DQfD3y1dXQj mqcA== X-Gm-Message-State: AOAM530IbiwB6PwiYyGKL5gc3Y8b0SWxu17zvsrYF1x2+kN9KaZNsPT9 lLLXpr1z8VveWrPjhwjG4saqgg== X-Google-Smtp-Source: ABdhPJwU4/RFcwCT/6MW8VqKMPUyd1Q4rfOckVO1M7ldoyPYS00f319cNKXtA1SMP5UWcJ74nHoNxw== X-Received: by 2002:a50:fb18:: with SMTP id d24mr211480edq.149.1599055537868; Wed, 02 Sep 2020 07:05:37 -0700 (PDT) Received: from tim.froidcoeur.net (ptr-7tznw14oqa3w7cibjsc.18120a2.ip6.access.telenet.be. [2a02:1811:50e:f0f0:8cba:3abe:17e1:aaec]) by smtp.gmail.com with ESMTPSA id os15sm4354775ejb.61.2020.09.02.07.05.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Sep 2020 07:05:36 -0700 (PDT) From: Tim Froidcoeur To: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org, gregkh@linuxfoundation.org, matthieu.baerts@tessares.net, davem@davemloft.net, Tim Froidcoeur Subject: [PATCH 4.4 2/2] net: initialize fastreuse on inet_inherit_port Date: Wed, 2 Sep 2020 16:05:13 +0200 Message-Id: <20200902140513.866712-3-tim.froidcoeur@tessares.net> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200902140513.866712-1-tim.froidcoeur@tessares.net> References: <20200902140513.866712-1-tim.froidcoeur@tessares.net> MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit d76f3351cea2d927fdf70dd7c06898235035e84e ] In the case of TPROXY, bind_conflict optimizations for SO_REUSEADDR or SO_REUSEPORT are broken, possibly resulting in O(n) instead of O(1) bind behaviour or in the incorrect reuse of a bind. the kernel keeps track for each bind_bucket if all sockets in the bind_bucket support SO_REUSEADDR or SO_REUSEPORT in two fastreuse flags. These flags allow skipping the costly bind_conflict check when possible (meaning when all sockets have the proper SO_REUSE option). For every socket added to a bind_bucket, these flags need to be updated. As soon as a socket that does not support reuse is added, the flag is set to false and will never go back to true, unless the bind_bucket is deleted. Note that there is no mechanism to re-evaluate these flags when a socket is removed (this might make sense when removing a socket that would not allow reuse; this leaves room for a future patch). For this optimization to work, it is mandatory that these flags are properly initialized and updated. When a child socket is created from a listen socket in __inet_inherit_port, the TPROXY case could create a new bind bucket without properly initializing these flags, thus preventing the optimization to work. Alternatively, a socket not allowing reuse could be added to an existing bind bucket without updating the flags, causing bind_conflict to never be called as it should. Call inet_csk_update_fastreuse when __inet_inherit_port decides to create a new bind_bucket or use a different bind_bucket than the one of the listen socket. Fixes: 093d282321da ("tproxy: fix hash locking issue when using port redirection in __inet_inherit_port()") Acked-by: Matthieu Baerts Signed-off-by: Tim Froidcoeur Signed-off-by: David S. Miller Signed-off-by: Tim Froidcoeur --- net/ipv4/inet_hashtables.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index ccc5980797fc..738cd5c822b1 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -160,6 +160,7 @@ int __inet_inherit_port(const struct sock *sk, struct sock *child) return -ENOMEM; } } + inet_csk_update_fastreuse(tb, child); } inet_bind_hash(child, tb, port); spin_unlock(&head->lock);