From patchwork Mon May 16 19:36:30 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 573291 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 40A81C43217 for ; Mon, 16 May 2022 20:07:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344099AbiEPUFe (ORCPT ); Mon, 16 May 2022 16:05:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54812 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348902AbiEPT7C (ORCPT ); Mon, 16 May 2022 15:59:02 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2D29B20F54; Mon, 16 May 2022 12:52:30 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BB2AB60A50; Mon, 16 May 2022 19:52:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BCDFBC385AA; Mon, 16 May 2022 19:52:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652730749; bh=HDvTOfzkdRxHd6HWC3WkqsEF8BETWp49rWnYi3S1Hlw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=l7B897HBsXIsZgBpJhgqWaHOqF2Vm6/FkNZdqKPbvNh1UXyMDZV5o7N+EfgyTxNcl SQhgpPt35NZMxNkdYsFWiyibP6KKAc016XgnYgb8NiUczvOENofME9i5jMU6pUV10R 03jU2fDPhQPLLGA/yfhyBEHjYfbE3Msxv24JQ0Hc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Jason A. Donenfeld" , Moshe Kol , Yossi Gilad , Amit Klein , Eric Dumazet , Willy Tarreau , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15 056/102] tcp: use different parts of the port_offset for index and offset Date: Mon, 16 May 2022 21:36:30 +0200 Message-Id: <20220516193625.604662759@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220516193623.989270214@linuxfoundation.org> References: <20220516193623.989270214@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Willy Tarreau [ Upstream commit 9e9b70ae923baf2b5e8a0ea4fd0c8451801ac526 ] Amit Klein suggests that we use different parts of port_offset for the table's index and the port offset so that there is no direct relation between them. Cc: Jason A. Donenfeld Cc: Moshe Kol Cc: Yossi Gilad Cc: Amit Klein Reviewed-by: Eric Dumazet Signed-off-by: Willy Tarreau Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/inet_hashtables.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index 606a4220ebb9..81a33af8393d 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -777,7 +777,7 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, net_get_random_once(table_perturb, sizeof(table_perturb)); index = hash_32(port_offset, INET_TABLE_PERTURB_SHIFT); - offset = READ_ONCE(table_perturb[index]) + port_offset; + offset = READ_ONCE(table_perturb[index]) + (port_offset >> 32); offset %= remaining; /* In first pass we try ports of @low parity.