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=-5.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 1053BC49EA2 for ; Fri, 18 Jun 2021 10:24:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DFEBB613C1 for ; Fri, 18 Jun 2021 10:24:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232479AbhFRK0v (ORCPT ); Fri, 18 Jun 2021 06:26:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:46118 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230340AbhFRK0t (ORCPT ); Fri, 18 Jun 2021 06:26:49 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 87F616117A; Fri, 18 Jun 2021 10:24:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1624011879; bh=D4AuELaLNiFNv3CP+vGfYuaFK7KeBacpL83m0TZ33VE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=BbweEaz375f0SKyqNBp8/jwO5GQ0a4ahI+O21R6sJZvmUaP8DZVAPQ9mZi/kseyO2 7/KnqM3ZhcZIUU1mTpSEPgsA4v+cH+rBy8mEV/v4m9PRjpFcL1oS9sfmZUZWeiWgE9 TeAMkNZID6ErNSCd6GM1ObsAemliqy1uVv7CZbUc= Date: Fri, 18 Jun 2021 12:24:36 +0200 From: Greg KH To: Amit Klein Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, edumazet@google.com, w@1wt.eu, davem@davemloft.net, netdev@vger.kernel.org Subject: Re: [PATCH 4.14] inet: use bigger hash table for IP ID generation (backported to 4.14) Message-ID: References: <60cc6c9a.1c69fb81.70a57.7034@mx.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <60cc6c9a.1c69fb81.70a57.7034@mx.google.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 18, 2021 at 02:51:22AM -0700, Amit Klein wrote: > Subject: inet: use bigger hash table for IP ID generation (backported to 4.14) > From: Amit Klein > > This is a backport to 4.14 of the following patch, originally > developed by Eric Dumazet. > > In commit 73f156a6e8c1 ("inetpeer: get rid of ip_id_count") > I used a very small hash table that could be abused > by patient attackers to reveal sensitive information. > > Switch to a dynamic sizing, depending on RAM size. > > Typical big hosts will now use 128x more storage (2 MB) > to get a similar increase in security and reduction > of hash collisions. > > As a bonus, use of alloc_large_system_hash() spreads > allocated memory among all NUMA nodes. > > Fixes: 73f156a6e8c1 ("inetpeer: get rid of ip_id_count") > Reported-by: Amit Klein > Cc: stable@vger.kernel.org > Cc: Eric Dumazet > Cc: Willy Tarreau > --- What is the git commit id of this patch in Linus's tree? thanks, greg k-h