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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 C22A9C32750 for ; Fri, 2 Aug 2019 04:16:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 789E92087E for ; Fri, 2 Aug 2019 04:16:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="VxQBTnWH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731287AbfHBEQD (ORCPT ); Fri, 2 Aug 2019 00:16:03 -0400 Received: from mail-pg1-f195.google.com ([209.85.215.195]:43569 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731101AbfHBEQD (ORCPT ); Fri, 2 Aug 2019 00:16:03 -0400 Received: by mail-pg1-f195.google.com with SMTP id r22so7773970pgk.10 for ; Thu, 01 Aug 2019 21:16:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=Vrw6OYJsWLjp309gunnnPWhv9UhyhI2DiwbJqag314w=; b=VxQBTnWHrisKFe5GYMOwsqQm80WhNPPx6ZIvvBL/ND82yftRR0KyUiSbBjzd47AZCH HnwbocW1MCwNyCaO41eaxIpenidXWnKykuH8gRHFoB/5foBrQa12ekgEXlOrQ2LeukON uXiUgZ0M2XBC13XjjF0zQpiG/6XJQo8V/P6COjSOqzgsGfIKMPFz++0q21Q7qLz6n/LN Pmov+7ggLkyUPu5trUx506t3thnb3XYo7cPtfm6GyAcNjTz7E0Nq8bihh+oDuC54WAnJ 6lCPb5KHX4cyRGJ9Cm/DwTioLNG3g1mAygmz8pOtKGro19o1OwX/P9sAYkFEGf9Xn8Mf p5aw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=Vrw6OYJsWLjp309gunnnPWhv9UhyhI2DiwbJqag314w=; b=f46VrbuacvocGpYb7DMXfK11akFJa+VPb2aIwbjCMZ1U40K09PGIoKczVRUUMZDIxL 3aWQBSrozNJe4rR6ip5EwtpTfQtWTp5b5bbWaZI5+aNSR17VGXyI6ZK3ggwXbVGklfnj 5x8VMxy9AQDOYicStoV7T8xZV9wfy6O4je6FU1wQfokcD6arI4y2wg78aKYBvcZFOEOe SMKn7HD6Jql1Thk5WR5aL+sujxoP89+frpBX3cs6tyLZJAvAkPTUNalprI18/Xw0+OZ6 XHVDg8/8TV7c/I3FSPU8C/QZLbllO5wpWK0hNCjFqy8dkMJj/JtPoLxJtZClT1uLwiqw gq6Q== X-Gm-Message-State: APjAAAXcMmGTp7ONqwPgd39hgVaVMp8v9pjYFGjKt6nEpYsHhBPziPal DfiujwEkxteaPsEUyBCgPpzUePww X-Google-Smtp-Source: APXvYqxTTHZe8VAfO6dadr2DteNRaRLJRkCV1PTJnbzYp87jSYT92JAXrev08Aru5/Sb3M6HQBe86w== X-Received: by 2002:a63:6eca:: with SMTP id j193mr46434720pgc.74.1564719362535; Thu, 01 Aug 2019 21:16:02 -0700 (PDT) Received: from [172.27.227.205] ([216.129.126.118]) by smtp.googlemail.com with ESMTPSA id i123sm100981500pfe.147.2019.08.01.21.16.01 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 01 Aug 2019 21:16:01 -0700 (PDT) Subject: Re: [PATCH net] ipv4/route: do not check saddr dev if iif is LOOPBACK_IFINDEX To: Hangbin Liu Cc: netdev@vger.kernel.org, Stefano Brivio , Marcelo Ricardo Leitner , "David S . Miller" References: <20190801082900.27216-1-liuhangbin@gmail.com> <20190802041358.GT18865@dhcp-12-139.nay.redhat.com> From: David Ahern Message-ID: <209d2ebf-aeb1-de08-2343-f478d51b92fa@gmail.com> Date: Thu, 1 Aug 2019 22:16:00 -0600 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20190802041358.GT18865@dhcp-12-139.nay.redhat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 8/1/19 10:13 PM, Hangbin Liu wrote: > On Thu, Aug 01, 2019 at 01:51:25PM -0600, David Ahern wrote: >> On 8/1/19 2:29 AM, Hangbin Liu wrote: >>> Jianlin reported a bug that for IPv4, ip route get from src_addr would fail >>> if src_addr is not an address on local system. >>> >>> \# ip route get 1.1.1.1 from 2.2.2.2 >>> RTNETLINK answers: Invalid argument >> >> so this is a forwarding lookup in which case iif should be set. Based on > > with out setting iif in userspace, the kernel set iif to lo by default. right, it presumes locally generated traffic. > >> the above 'route get' inet_rtm_getroute is doing a lookup as if it is >> locally generated traffic. > > yeah... but what about the IPv6 part. That cause a different behavior in > userspace. just one of many, many annoying differences between v4 and v6. We could try to catalog it.