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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35E90C77B6C for ; Wed, 12 Apr 2023 23:06:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229869AbjDLXG6 (ORCPT ); Wed, 12 Apr 2023 19:06:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229847AbjDLXG4 (ORCPT ); Wed, 12 Apr 2023 19:06:56 -0400 Received: from relay11.mail.gandi.net (relay11.mail.gandi.net [IPv6:2001:4b98:dc4:8::231]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 246D3658A for ; Wed, 12 Apr 2023 16:06:54 -0700 (PDT) Received: (Authenticated sender: schoen@loyalty.org) by mail.gandi.net (Postfix) with ESMTPSA id D3F1E100004 for ; Wed, 12 Apr 2023 23:06:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=loyalty.org; s=gm1; t=1681340813; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type; bh=1SiyjX0B5Fkh7PzM/30AYYXrZQJeVUmQqy589HdsTj0=; b=eiaVJ/XLSWFbHQiusUb7Uj/B/qjfycpk534LSkH3v1PComBCj4WCWgc2It7bouTljcZYA/ bOkMDiCDl2qIACXwcRyMIP0V5ykp7xjgKkVDbmaopGelQGAQE4laom/pxd13tAwF15A0vi MDA5bo5kHU78Vs+zelguMFcGpy5vmXvWaql0ShYEKS0iAYyevIvpUlNRTi0PfsTxp7A5mG 9ZqlTXcCrdV+x77782E6n9eAjSNZ7Imq5Nc3i73I6qbOeLx/Hw/J2zDc6JGB8xIDJyelx/ eJeZOsFH+QLId0rXwio1yaDpbt55mGPl+sLeLvg2q6YrSJ2dm2V58wFoLJ//xQ== Date: Wed, 12 Apr 2023 16:06:49 -0700 From: Seth David Schoen To: linux-man Subject: ip.7 update on treatment of reserved addresses? Message-ID: <20230412230649.GA2462622@demorgan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-man@vger.kernel.org Hi, I've submitted a patch a couple of times that adds more detailed information in ip.7 about how the Linux kernel treats reserved IPv4 addresses. (There is some discussion already there, but it's not entirely comprehensive and up-to-date with respect to the current behavior.) I'm paying attention to this because I've been actively involved in efforts to get the kernel to treat these addresses more permissively than historical standards suggest -- which it indeed does. I haven't gotten any feedback on my patch on the occasions when I've submitted it, so I thought I'd ask directly whether anyone is interested in reviewing it or discussing it, or whether there would be any interest in expanding the documentation on this point under any circumstances. Thanks! (specifically, Linux now permits you to assign the lowest, or "network", address on a segment as a unicast address; it has for several years permitted you to assign addresses from within 0/8; it has for many years permitted you to assign addresses from within 240/4; and all of these are also accepted as valid unicast destinations -- none of which users would assume just from reading RFCs!)