From nobody Wed Jan 24 16:28:38 2024 X-Original-To: dev-commits-src-main@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4TKqD95HrZz58Jph; Wed, 24 Jan 2024 16:29:29 +0000 (UTC) (envelope-from herbert@gojira.at) Received: from mail.bsd4all.net (mail.bsd4all.net [94.130.200.20]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature ECDSA (P-384) client-digest SHA384) (Client CN "mail.bsd4all.net", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4TKqD92k7jz4v1Q; Wed, 24 Jan 2024 16:29:29 +0000 (UTC) (envelope-from herbert@gojira.at) Authentication-Results: mx1.freebsd.org; none Date: Wed, 24 Jan 2024 17:28:38 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=gojira.at; s=mail202005; t=1706113767; bh=rP0lzA1yaXhB06G/N9KZuNiV72P6EGWrdrvMozFNEbE=; h=Date:Message-ID:From:To:Cc:Subject:MIME-Version:Content-Type; b=kieNowSaKHw5RIeRofZonS2wumGt0GrHhngVAwCoQm9lB9OG2UFlPGpunPuk5CY9C izxH0jnGPnFx3nvMixNacnk+pLmKny2byPXRtNQr5zx3ThXfwjbgMQSIXIE1GI7nrP F/2DiJRf6tQOObuZNskPEc9RGhj4nMYCumD09MmaN49pabFyxRJzGs3gliO4uAhX5f LjJcwNcbkN3+pNloCLe8Mp8tL3OFcrF6PJlEaqi/CCvGFWGxF4U+lbkMhjbS1bWOBV 37jHb8hY6Mf4OjKVItNOLfF8jKvQirFvbxjYWoigN9Zh6TGIfhkfJGyYtfKqRjHy1u /Zh428NK/j2Qg== Message-ID: <87jznylmq1.wl-herbert@gojira.at> From: "Herbert J. Skuhra" To: Kristof Provost Cc: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: Re: git: 54c62e3e5d8c - main - pf: work around icmp6 packet-too-big not being sent when binat-ing In-Reply-To: <880FAE40-9D91-4AA6-92BA-2D582D23B745@FreeBSD.org> References: <202401221252.40MCqpf6047526@gitrepo.freebsd.org> <87v87jkii9.wl-herbert@gojira.at> <1E1C3472-0AF3-457B-A27A-89679770EA62@FreeBSD.org> <87sf2nm4et.wl-herbert@gojira.at> <880FAE40-9D91-4AA6-92BA-2D582D23B745@FreeBSD.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) Emacs/29.2 Mule/6.0 List-Id: Commit messages for the main branch of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-main List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-main@freebsd.org X-BeenThere: dev-commits-src-main@freebsd.org MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-Rspamd-Queue-Id: 4TKqD92k7jz4v1Q X-Spamd-Bar: ---- X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:24940, ipnet:94.130.0.0/16, country:DE] On Wed, 24 Jan 2024 14:27:19 +0100, Kristof Provost wrote: > On 24 Jan 2024, at 11:06, Herbert J. Skuhra wrote: > > On Tue, 23 Jan 2024 19:42:10 +0100, Kristof Provost wrote: > >> On 23 Jan 2024, at 19:32, Herbert J. Skuhra wrote: > >>> On Mon, 22 Jan 2024 13:52:51 +0100, Kristof Provost wrote: > >>>> > >>>> The branch main has been updated by kp: > >>>> > >>>> URL: > >>>> https://cgit.FreeBSD.org/src/commit/?id=54c62e3e5d8cd90c5571a1d4c8c5f062d580480e > >>>> > >>>> commit 54c62e3e5d8cd90c5571a1d4c8c5f062d580480e > >>>> Author: Kristof Provost > >>>> AuthorDate: 2024-01-17 17:11:27 +0000 > >>>> Commit: Kristof Provost > >>>> CommitDate: 2024-01-22 11:52:14 +0000 > >>>> > >>>> pf: work around icmp6 packet-too-big not being sent when > >>>> binat-ing > >>>> > >>>> If we're applying NPTv6 we pass a packet with a modified > >>>> source and/or > >>>> destination address to the network stack. > >>>> > >>>> If that packet then turns out to be larger than the MTU of > >>>> the sending > >>>> interface the stack will attempt to generate an icmp6 > >>>> packet-too-big > >>>> error, but may fail to look up the appropriate source address > >>>> for that > >>>> error message. Even if it does, pf would still have to undo > >>>> the binat > >>>> operation inside the icmp6 packet so the sending host can > >>>> make sense of > >>>> the error. > >>>> > >>>> We can avoid both problems entirely by having pf also perform > >>>> the MTU > >>>> check (taking the potential refragmentation into account), and > >>>> generating the icmp6 error directly in pf. > >>>> > >>>> See also: https://redmine.pfsense.org/issues/14290 > >>>> Sponsored by: Rubicon Communications, LLC ("Netgate") > >>>> Differential Revision: https://reviews.freebsd.org/D43499 > >>>> --- > >>>> sys/net/pfvar.h | 1 + > >>>> sys/netpfil/pf/pf.c | 12 ++++++++++++ > >>>> sys/netpfil/pf/pf_norm.c | 15 +++++++++++++++ > >>>> 3 files changed, 28 insertions(+) > >>> > >>> Does this change cause problems for others too? > >>> > >>> - ssh over IPv6 permanently disconnecting > >>> (client_loop: send disconnect: Broken pipe) > >>> - ssh connections over IPv6 hanging > >>> - git pull not working > >>> Fssh_ssh_dispatch_run_fatal: Connection to > >>> 2604:1380:4091:a001::24ca:1 port 22: Permission denied > >>> fatal: Could not read from remote repository. > >>> > >> Can you include your pf.conf and a packet capture demonstrating one > >> of these issues? > > > > So I assume this issue affects only me or this server (igb nic). > > Disabling tso6 seems to resolve the issue. > > > Ah. A Clue(tm)! > > Try this: > > diff --git a/sys/netpfil/pf/pf.c b/sys/netpfil/pf/pf.c > index 38a5a45d7991..2dc6d02d330a 100644 > --- a/sys/netpfil/pf/pf.c > +++ b/sys/netpfil/pf/pf.c > @@ -8515,7 +8515,7 @@ pf_test6(int dir, int pflags, struct > ifnet *ifp, struct mbuf **m0, struct inpcb > * confused and fail to send the icmp6 packet too big > error. Just send > * it here, before we do any NAT. > */ > - if (dir == PF_OUT && IN6_LINKMTU(ifp) < pf_max_frag_size(m)) { > + if (dir == PF_OUT && pflags & PFIL_FWD && > IN6_LINKMTU(ifp) < pf_max_frag_size(m)) { > PF_RULES_RUNLOCK(); > *m0 = NULL; > icmp6_error(m, ICMP6_PACKET_TOO_BIG, 0, > IN6_LINKMTU(ifp)); This patch fixes the issue. Thanks a lot. -- Herbert