From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E07586F30B; Thu, 12 Sep 2024 21:11:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726175472; cv=none; b=LktLq+SznQVmT0R0XSjfU4ZpT6di61Q93Pjkiw0zaX0mV+hmEXPv9vF8NZXUNkK/mEi4hdUBKbVKlb9huXZRSq7NuJ6Lx+o+BNevEWxuG+ckb2jzqu69yC6aJw3gT3A9wfu+TDXlDdnV77qaDI5HmaRfE/2s6DmcobpPbnJMSS4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726175472; c=relaxed/simple; bh=2As3YcV87aGciE6ArbRCpb0o3izQVEQHoUfMUN6G7Rc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=V6DVuJsThDoViOjQVyMwygBudbzb8XfttppyL9HjPRBAzFbdP3fLjVEJ53j+yDMSDYxTiq9/PknmQjoznd5fv2XUtAHqGtWP+xhdIlt4fn46pyZxBMDv08TZLmnc4cNDMpFyIgRYuHSNp9cMIlADARikXD+Svao464hOP9bLdf4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DVnMfy2m; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DVnMfy2m" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 56243C4CEC3; Thu, 12 Sep 2024 21:11:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1726175471; bh=2As3YcV87aGciE6ArbRCpb0o3izQVEQHoUfMUN6G7Rc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=DVnMfy2mgG2YxnUfZh4QeORAVB0r2IvKnjuj+/IA0IwpJy926rbj3fKHsAgN/aKAu MhToU7PM3AaakLY1Oj0gW9q6V6S3w0vfrAS0dMnqPLXirYCMsKc4KJulvCbBOwc5v+ 3B5ZT0XWAV/ZogFUb+xqA9ZMH/cUH7w+za47qZHkhYxpeV/UuuH02JVplDUnG4FkXu kLnJVZu4b1hb7Fw2lDQgf/C7g7AQXaLORS0v5RuBDpYNSdjdORlV5GCzJBL1j6M4Ck meAx8Wsardw92fgW1z+Ob6S8gu2xIz+DHIQ1Njj2sMqmYYp0XXPc6nTHnraKQmeVRf 2Ma3b5pZY4pdQ== Received: by pali.im (Postfix) id C6DCF5E9; Thu, 12 Sep 2024 23:11:06 +0200 (CEST) Date: Thu, 12 Sep 2024 23:11:06 +0200 From: Pali =?utf-8?B?Um9ow6Fy?= To: Anna Schumaker Cc: Trond Myklebust , Anna Schumaker , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/5] nfs: Fix mounting NFS3 AUTH_NULL exports Message-ID: <20240912211106.2osqf5voyyjlran7@pali> References: <20240912130220.17032-1-pali@kernel.org> 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=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: NeoMutt/20180716 On Thursday 12 September 2024 17:06:07 Anna Schumaker wrote: > Hi Pali, > > On 9/12/24 9:02 AM, Pali Rohár wrote: > > Linux NFS3 kernel client currently has broken support for NFS3 > > AUTH_NULL-only exports and also broken mount option -o sec=none > > (which explicitly specifies that mount should use AUTH_NULL). > > > > For AUTH_NULL-only server exports, Linux NFS3 kernel client mounts such > > export with AUTH_UNIX authentication which results in unusable mount > > point (any operation on it fails with error because server rejects > > AUTH_UNIX authentication). > > > > Half of the problem is with MNTv3 servers, as some of them (e.g. Linux > > one) never announce AUTH_NULL authentication for any export. Linux MNTv3 > > server does not announce it even when the export has the only AUTH_NULL > > auth method allowed, instead it announce AUTH_UNIX (even when AUTH_UNIX > > is disabled for that export in Linux NFS3 knfsd server). So MNTv3 server > > for AUTH_NONE-only exports instruct Linux NFS3 kernel client to use > > AUTH_UNIX and then NFS3 server refuse access to files with AUTH_UNIX. > > > > Main problem on the client side is that mount option -o sec=none for > > NFS3 client is not processed and Linux NFS kernel client always skips > > AUTH_NULL (even when server announce it, and also even when user > > specifies -o sec=none on mount command line). > > > > This patch series address these issues in NFS3 client code. > > > > Add a workaround for buggy MNTv3 servers which do not announce AUTH_NULL, > > by trying AUTH_NULL authentication as an absolutely last chance when > > everything else fails. And honors user choice of AUTH_NULL if user > > explicitly specified -o sec=none as mount option. > > Why fix this on the client instead of fixing the server to announce AUTH_NULL > if this is what the user has configured? This can be a next step. Without this client workaround it is not possible to connect with Linux client to existing/running servers. > Anna > > > > > AUTH_NULL authentication is useful for read-only exports, including > > public exports. As authentication for these types of exports do not have > > to be required. > > > > Patch series was tested with AUTH_NULL-only, AUTH_UNIX-only and combined > > AUTH_NULL+AUTH_UNIX exports from Linux knfsd NFS3 server + default Linux > > MNTv3 userspace server. And also tested with exports from modified MNTv3 > > server to properly return AUTH_NULL support in response list. > > > > Patch series is based on the latest upstream tag v6.11-rc7. > > > > Pali Rohár (5): > > nfs: Fix support for NFS3 mount with -o sec=none from Linux MNTv3 > > server > > nfs: Propagate AUTH_NULL/AUTH_UNIX PATHCONF NFS3ERR_ACCESS failures > > nfs: Try to use AUTH_NULL for NFS3 mount when no -o sec was given > > nfs: Fix -o sec=none output in /proc/mounts > > nfs: Remove duplicate debug message 'using auth flavor' > > > > fs/nfs/client.c | 14 ++++++++++- > > fs/nfs/super.c | 64 +++++++++++++++++++++++++++++++++++++++---------- > > 2 files changed, 65 insertions(+), 13 deletions(-) > >