From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f44.google.com (mail-wm1-f44.google.com [209.85.128.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7166030BBB6 for ; Wed, 19 Nov 2025 04:50:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.44 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763527823; cv=none; b=YkXvJnvALHjSpJ990RowSYS2vPwF1deUAptLnk9ZN+wmTM4O/y56L7Ot5Kt82PLcp2N4l3L8SVedKgPdG5wCp5wVTkN59GUonYriuHUiy3QBozfRRQBxWxHoGpd+mKQoXAsrKbBvV3CvYWLEeUMKEwNfaYqsafz5WVR0GZGtFQM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763527823; c=relaxed/simple; bh=uy5eSpV62p2H09YQGx8yG5S4D6+C+pY0E+tpBih96uA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UefGLYnOraAF13Em7bVJMWoRI1Zut3Y3lD0x8rjhSMDorPTDSUuxD1ccEOmHErM5peKqZnWg+g9jEYSEskeiIqSxPdfvSMxbkWUwwrVBObaMJj562XqpCSAekdjwjRLaaODB8ipJbnlBSYxqPWzXj+ONosfcgiQsOtOoxIyPZWc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=debian.org; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=jn0dDYrJ; arc=none smtp.client-ip=209.85.128.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=debian.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="jn0dDYrJ" Received: by mail-wm1-f44.google.com with SMTP id 5b1f17b1804b1-47796a837c7so25221505e9.0 for ; Tue, 18 Nov 2025 20:50:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1763527820; x=1764132620; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=mDkvoxkCuh3RNYeupEaeAKJkLqKVA+WiXtH4iTHXg2c=; b=jn0dDYrJiR9XDvQ7V8vo1i5uSj4OnwTVKVxermvxSw+ke4S1d9V3eFNj3wtWIwMSgO E1atGmy8mG0Cz4oNb6Zj2W77zjZW2qDvkF3m1chDSVtGw1tmlw0DpZx0FHAyJk8QHDa0 HbjTx3FlxWiDQC99KQezwKZRFETeUig7fvnPcgovxaGQUDljRKv2KiIH93j/trVY/L/y sejDFL+N4PpbJ/j7V0lnIkGgz/mwavczhlxAQZoBKDhmOEui/OxZLuiUDPZ2bV7FagNT 76VUKKRtDLJw19wZh6OeGdGzbjE5KQ5IsZ/byAAW+aTedOImDyR4lUus4ZObVDtpPmB2 zx1g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1763527820; x=1764132620; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-gg:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=mDkvoxkCuh3RNYeupEaeAKJkLqKVA+WiXtH4iTHXg2c=; b=NDcAX3WjhigvbHxPcPKGftz0zNlbkOzOiqRZrU3XYLK4NmMDiYbax2N4g3gTADZsyv wEezx2FEJcxR6cxrsC+Jr0Yi54Gcuq8f6WVdHnv8ZYii7X6b62f90iolJ7FKr2cWYi/z Eu5vZRQshp+DZoIaLVdny4MAOp6tc3fIS5T3fFKR3aDAh6+LfZAr1wqwVYwar69/8T+A VSzArXdb1OYyE0TUi1XFDThNB/gJhcd9sPlL5O3AsZeRhv7EhmD80OVJbYpLquDcLrfY iIRnFeq4MEo0Z7seojE5rIjawazz5grCY4Up7Hr4TwMDJXpdhaFtNHrfl4jNy6nUW87Y Pm+A== X-Forwarded-Encrypted: i=1; AJvYcCXeK6Siy0ylF3JlsmkWKRKT4c+Dq5GJa7ADS988QcCPlvZfLgE/9XaCCguwhZmZDPCtIKl4VtZklLq4iKI=@vger.kernel.org X-Gm-Message-State: AOJu0YzFRAusvkHgvV2pC2dTfFMiKC9xhmHzZ79FGPT7L4+7u5uPm0or vOfIk/QC9J5PoEsEkSgsaw7UMi4qcL6gJeHRnbosMmPXI89fSbOPnJba X-Gm-Gg: ASbGncvarnrmU7TAKhtiRzHr11lR6PFrwXIDAqRwDklDo9+0HPFRXly0K+EIGCf5ymD q0hdEGAp1Dio1nvkVwzebABGy5C4knvcuYBZs8orBFWao4bDOOKp7eqMf4Bl3X8NE9LnFyXRBlx vqbLMBkae7/0DH0YSQOOehM26OimWWe8sIzxmdF1dhLsDw8GewKXwh1WW9WP589LsEI7mgnlxhR GIHhu5+xj1TIPklZHFxOK7XCWeu4hr15Q4MT6OqNJ0V9N5moAS9mzzbNaQmcGEjcja5L2DuLC6C 9ApK+juAQRzXSiDt64obXttrm8FtLb5cA/zdZmFqHnSgJ8Ob4iFxRVY1/FwfsuLHP5L79g8gS9+ rkkotznQJFK1y95mHKkggh1iGO8e2rp6tt4RrCcSdzAsFy7usWe+pOOoubL/NqpjHsqGQBI51yn 1KVyYEbPykqWOwg1k5w9xYazGu9qqcTJmtGiJ3j7qwiwEG X-Google-Smtp-Source: AGHT+IGwH2FkmhtLEuoN+9sHrL7YCOIrIrpSZDkyGAZ4ZW1s1xHCUII58dtc7cgvRdhgt4WF/jjH9g== X-Received: by 2002:a05:600c:1550:b0:477:7b16:5fa6 with SMTP id 5b1f17b1804b1-477b197ab08mr6588565e9.3.1763527819440; Tue, 18 Nov 2025 20:50:19 -0800 (PST) Received: from eldamar.lan (c-82-192-244-13.customer.ggaweb.ch. [82.192.244.13]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-477b106b03bsm24955065e9.9.2025.11.18.20.50.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Nov 2025 20:50:18 -0800 (PST) Sender: Salvatore Bonaccorso Received: by eldamar.lan (Postfix, from userid 1000) id 258B0BE2EE7; Wed, 19 Nov 2025 05:50:17 +0100 (CET) Date: Wed, 19 Nov 2025 05:50:17 +0100 From: Salvatore Bonaccorso To: "Tyler W. Ross" Cc: Scott Mayhew , Trond Myklebust , Chuck Lever , Anna Schumaker , "1120598@bugs.debian.org" <1120598@bugs.debian.org>, Jeff Layton , NeilBrown , Steve Dickson , Olga Kornievskaia , Dai Ngo , Tom Talpey , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Simon Josefsson Subject: Re: ls input/output error ("NFS: readdir(/) returns -5") on krb5 NFSv4 client using SHA2 Message-ID: References: <4a63ad3d-b53a-4eab-8ffb-dd206f52c20e@oracle.com> <902ff4995d8e75ad1cd2196bf7d8da42932fba35.camel@kernel.org> <85cd9202-dc22-41b8-8a20-e82cd118215f@TylerWRoss.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <85cd9202-dc22-41b8-8a20-e82cd118215f@TylerWRoss.com> Hi, On Tue, Nov 18, 2025 at 11:43:29PM +0000, Tyler W. Ross wrote: > On 11/18/25 10:52 AM, Scott Mayhew wrote: > > Oh! I see the problem. If the automatically acquired service ticket > > for a normal user is using aes256-cts-hmac-sha1-96, then I'm assuming > > the machine credential is also using aes256-cts-hmac-sha1-96. > > Run 'klist -ce /tmp/krb5ccmachine_IPA.TWRLAB.NET' to check. You can't > > use 'kvno -e' to choose a different encryption type. Why are you doing > > that? > > Aha! Thank you! Thanks to all helping to debug this issue when reported downstream in Debian, your time invested is very much appreciated! > That's exactly the case: the machine credential is > aes256-cts-hmac-sha1-96. > > So, taking a step back for context/background: this issue was escalated to > me by someone attempting to use constrained delegation via gssproxy. In the > course of troubleshooting that, we found (by examining the krb5kdc logs on > the IPA server) that the NFS service ticket acquired by gssproxy had an > aes256-cts-hmac-sha384-192 session key. > > Not understanding that the machine and user tickets must having matching > enctypes, I ended up down this rabbit hole thinking the problem > was with the SHA2 enctypes. Sorry to bring you all with me on that > misadventure. > > > > The actual issue at hand then seems to be that gssproxy is requesting (and > receiving) a service ticket with an unusable (for the NFS mount) enctype, > when performing constrained delegation/S4U2Proxy. > > krb5kdc logs of gssproxy performing S4U2Self and S4U2Proxy:Nov 18 18:06:51 > directory.ipa.twrlab.net krb5kdc[8463](info): TGS_REQ (8 etypes > {aes256-cts-hmac-sha1-96(18), aes128-cts-hmac-sha1-96(17), > aes256-cts-hmac-sha384-192(20), aes128-cts-hmac-sha256-128(19), > UNSUPPORTED:des3-hmac-sha1(16), DEPRECATED:arcfour-hmac(23), > camellia128-cts-cmac(25), camellia256-cts-cmac(26)}) 10.108.2.105: ISSUE: > authtime 1763506600, etypes {rep=aes256-cts-hmac-sha1-96(18), > tkt=aes256-cts-hmac-sha384-192(20), ses=aes256-cts-hmac-sha1-96(18)}, > host/nfsclient.ipa.twrlab.net@IPA.TWRLAB.NET for > host/nfsclient.ipa.twrlab.net@IPA.TWRLAB.NET > Nov 18 18:06:51 directory.ipa.twrlab.net krb5kdc[8463](info): > ... PROTOCOL-TRANSITION s4u-client=jsmith@IPA.TWRLAB.NET > Nov 18 18:06:51 directory.ipa.twrlab.net krb5kdc[8463](info): closing down > fd 4 > Nov 18 18:06:51 directory.ipa.twrlab.net krb5kdc[8465](info): TGS_REQ (4 > etypes {aes256-cts-hmac-sha384-192(20), aes128-cts-hmac-sha256-128(19), > aes256-cts-hmac-sha1-96(18), aes128-cts-hmac-sha1-96(17)}) 10.108.2.105: > ISSUE: authtime 1763506600, etypes {rep=aes256-cts-hmac-sha1-96(18), > tkt=aes256-cts-hmac-sha384-192(20), ses=aes256-cts-hmac-sha384-192(20)}, > host/nfsclient.ipa.twrlab.net@IPA.TWRLAB.NET for > nfs/nfssrv.ipa.twrlab.net@IPA.TWRLAB.NET > Nov 18 18:06:51 directory.ipa.twrlab.net krb5kdc[8465](info): ... > CONSTRAINED-DELEGATION s4u-client=jsmith@IPA.TWRLAB.NET > Nov 18 18:06:51 directory.ipa.twrlab.net krb5kdc[8465](info): closing down > fd 11 > > > On the Fedora 43 client, gssproxy also acquires an > aes256-cts-hmac-sha384-192 service ticket, but the machine credential is > aes256-cts-hmac-sha384-192 and everything works as-ex > pected. I'm looping in here the gssproxy maintainer as well. Simon, this is about https://bugs.debian.org/1120598 . I assume there is nothing on gssroxy side which can be done to warn about the situation, quoting again: > The actual issue at hand then seems to be that gssproxy is requesting (and > receiving) a service ticket with an unusable (for the NFS mount) enctype, > when performing constrained delegation/S4U2Proxy. ? Regards, Salvatore