From owner-freebsd-net@freebsd.org Wed Jan 13 08:43:34 2021 Return-Path: Delivered-To: freebsd-net@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id BE2794D51AA for ; Wed, 13 Jan 2021 08:43:34 +0000 (UTC) (envelope-from bu7cher@yandex.ru) Received: from forward105p.mail.yandex.net (forward105p.mail.yandex.net [IPv6:2a02:6b8:0:1472:2741:0:8b7:108]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4DG1F13dhMz3rM1 for ; Wed, 13 Jan 2021 08:43:33 +0000 (UTC) (envelope-from bu7cher@yandex.ru) Received: from myt6-2cec5828668a.qloud-c.yandex.net (myt6-2cec5828668a.qloud-c.yandex.net [IPv6:2a02:6b8:c12:4019:0:640:2cec:5828]) by forward105p.mail.yandex.net (Yandex) with ESMTP id 027F44D410C2; Wed, 13 Jan 2021 11:43:30 +0300 (MSK) Received: from myt2-accb38a5c431.qloud-c.yandex.net (myt2-accb38a5c431.qloud-c.yandex.net [2a02:6b8:c00:2e9b:0:640:accb:38a5]) by myt6-2cec5828668a.qloud-c.yandex.net (mxback/Yandex) with ESMTP id GI8LSeB4Zu-hTGqYxJT; Wed, 13 Jan 2021 11:43:29 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex.ru; s=mail; t=1610527409; bh=VKMVf4jjWPKIh3rU0KU0uAIo9umTpp8BBXMnf0dNAA4=; h=In-Reply-To:From:Date:References:To:Subject:Message-ID; b=wdk4c9tQPG4VldxnO60jcejYlYdedr32LX5FmxQ3YRAZGfOay/F1BEDFps9EJBQbm cOqY12pw7IOHcvQ2w9xjBkm/z9pnRQjOhd+mMZtqNREHBLS3I8vGPnXdxREuVWnM2j hudWReHvLiO9PLghU11BXe6mveVtY2JujIoNEdXk= Received: by myt2-accb38a5c431.qloud-c.yandex.net (smtp/Yandex) with ESMTPSA id tMVCrdb9jC-hTH0kTo8; Wed, 13 Jan 2021 11:43:29 +0300 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (Client certificate not present) Subject: Re: FreeBSD does not reply to IPv6 Neighbor Solicitations To: Lutz Donnerhacke , freebsd-net@freebsd.org, Hans Petter Selasky References: <20210105031528.GA91534@admin.sibptus.ru> <00a101d6e33b$96edf0c0$c4c9d240$@donnerhacke.de> <20210105104650.GA7688@admin.sibptus.ru> <00b601d6e35a$115a4a20$340ede60$@donnerhacke.de> <20210112022525.GN31099@funkthat.com> <95be49e2-56cc-cf3f-3515-8f13f14ddbad@yandex.ru> <20210112213707.GP31099@funkthat.com> From: "Andrey V. Elsukov" Message-ID: <065eaff7-35bd-0cd3-f68f-849be2178574@yandex.ru> Date: Wed, 13 Jan 2021 11:42:32 +0300 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: <20210112213707.GP31099@funkthat.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4DG1F13dhMz3rM1 X-Spamd-Bar: --- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=yandex.ru header.s=mail header.b=wdk4c9tQ; dmarc=pass (policy=none) header.from=yandex.ru; spf=pass (mx1.freebsd.org: domain of bu7cher@yandex.ru designates 2a02:6b8:0:1472:2741:0:8b7:108 as permitted sender) smtp.mailfrom=bu7cher@yandex.ru X-Spamd-Result: default: False [-3.52 / 15.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_FROM(0.00)[yandex.ru]; R_SPF_ALLOW(-0.20)[+ip6:2a02:6b8:0:1000::/52]; RCVD_COUNT_THREE(0.00)[4]; DKIM_TRACE(0.00)[yandex.ru:+]; DMARC_POLICY_ALLOW(-0.50)[yandex.ru,none]; NEURAL_HAM_SHORT(-0.42)[-0.420]; RCVD_IN_DNSWL_LOW(-0.10)[2a02:6b8:0:1472:2741:0:8b7:108:from]; RCVD_TLS_LAST(0.00)[]; RBL_DBL_DONT_QUERY_IPS(0.00)[2a02:6b8:0:1472:2741:0:8b7:108:from]; FREEMAIL_ENVFROM(0.00)[yandex.ru]; ASN(0.00)[asn:13238, ipnet:2a02:6b8::/32, country:RU]; MID_RHS_MATCH_FROM(0.00)[]; DWL_DNSWL_NONE(0.00)[yandex.ru:dkim]; MIME_TRACE(0.00)[0:+]; ARC_NA(0.00)[]; R_DKIM_ALLOW(-0.20)[yandex.ru:s=mail]; FROM_EQ_ENVFROM(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; FROM_HAS_DN(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; SPAMHAUS_ZRD(0.00)[2a02:6b8:0:1472:2741:0:8b7:108:from:127.0.2.255]; TO_MATCH_ENVRCPT_SOME(0.00)[]; MAILMAN_DEST(0.00)[freebsd-net] X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Jan 2021 08:43:34 -0000 On 13.01.2021 00:37, John-Mark Gurney wrote: >> when this will happen again, it would be nice to make sure that NS >> packets hit the IP stack. E.g. with attached dtrace script. > > Ok, I ran the dtrace script when I reproduced the problem, and it did > not produce any output. > > These are effectively what the script does: > 9) configure inet6 addresses on ure and bge (duplicating the addresses > already configured) Does it mean that you just reconfigure address without removing it? It looks like the problem, that was discussed here https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=233535 > bge0: > inet6 fe80::12e7:c6ff:fexx:xxxx%bge0 scopeid 0x2 > mldv2 flags=2 rv 2 qi 125 qri 10 uri 3 > group ff01::1%bge0 scopeid 0x2 mode exclude > mcast-macaddr 33:33:00:00:00:01 > group ff02::1%bge0 scopeid 0x2 mode exclude > mcast-macaddr 33:33:00:00:00:01 > group ff02::1:ffxx:xxxx%bge0 scopeid 0x2 mode exclude > mcast-macaddr 33:33:ff:xx:xx:xx > > so, I made things works, and ran ifmcstat again, and this time it has > an additional group in the output: > [...] > bge0: > inet6 fe80::12e7:c6ff:fexx:xxxx%bge0 scopeid 0x2 > mldv2 flags=2 rv 2 qi 125 qri 10 uri 3 > group ff02::1:ff00:c43c%bge0 scopeid 0x2 mode exclude > mcast-macaddr 33:33:ff:00:c4:3c > group ff01::1%bge0 scopeid 0x2 mode exclude > mcast-macaddr 33:33:00:00:00:01 > group ff02::1%bge0 scopeid 0x2 mode exclude > mcast-macaddr 33:33:00:00:00:01 > group ff02::1:ffxx:xxxx%bge0 scopeid 0x2 mode exclude > mcast-macaddr 33:33:ff:xx:xx:xx > > and the tcpdump output: > 21:10:53.938655 IP6 fc00:b5d:41c:7e37::7e37 > ff02::1:ff00:c43c: ICMP6, neighbor solicitation, who has fc00:b5d:41c:7e37::c43c, length 32 > 21:10:55.001428 IP6 fc00:b5d:41c:7e37::7e37 > ff02::1:ff00:c43c: ICMP6, neighbor solicitation, who has fc00:b5d:41c:7e37::c43c, length 32 Since ff02::1:ff00:c43c%bge0 is not configured in first case, IP stack just ignores NS messages and they don't hit ND6 code. In the PR 233535 the problem was reproducible with MLDv1, so if you disable MLDv2 will it work (to reduce possible scope of problematic code)? net.inet6.mld.v2enable=0 -- WBR, Andrey V. Elsukov