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 52B363FF89E; Wed, 29 Apr 2026 18:08:03 +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=1777486083; cv=none; b=o4ZW5xbiiL2z71yxYL1vyUu7tE2ObaDmSVqG7y4zTlzHc+ZMT/tSvROR8p+NO7+N5GbaHdn3mYP0gOahs9To7xgAUsnj0Hd7Y+RzwGDiY4VLCos0jXYbfxwfYQHAar9Bq3PzWM6NTybVEVC0iX/VOBS2CeR+1k+uy4RG2AWlb8k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777486083; c=relaxed/simple; bh=DMOslqY8hrgzhiEEpdlPHzlUOU2jtL44Gxm3Xa3n8gU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=p6MhJYnlfYHMcz9AXiceVVjlxtWDN+9RLtViu9d3ju3gADWe64lPz8DUvgB8hJ76wKkcXSAmQ5pRtXi+D1qK5hjoIu+2CUkge0DNnJ/XrmQLRVip1ycMGPwaUNWZaXomu8e8nqGxd6ubvqieNWbaSSn/cQ7vcibr9EHyfcFmAOw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bK2MxXZM; 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="bK2MxXZM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C15B8C2BCC4; Wed, 29 Apr 2026 18:08:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777486083; bh=DMOslqY8hrgzhiEEpdlPHzlUOU2jtL44Gxm3Xa3n8gU=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=bK2MxXZMLsCKyWAbA5jRd65cULoxSMxpWM+1P5HqbMkoFIt0SoRA6AGwLaYBql4aE pe9Ki58BFn0A9zSEw0TwNUXWTNpPUwvl5Squ6Ar/qKTaWVLX8P2BORBc/RWNyDyA3h eDnfUY+PL+qLNPYUvtrkNGlZ6AWmORXp4dQhFzuSnS65NGaoRc2GDiAOpWk5mKOJ4T Eaj6GOwVUIni6YVMPkdY9sNy95RgJYv1bnbwcxag/kKaFQdJ4MffT4RE19ps53ogOR UVCbBs180qfUrmZiV1ghU4PROgsEZ6GFFV1sL5qy/aySXOQeYWjQUsZpclbX6/AKeW LmjHxGZpFQuWA== From: Chuck Lever Date: Wed, 29 Apr 2026 14:07:25 -0400 Subject: [PATCH v12 14/15] nfsd: Implement NFSv4 FATTR4_CASE_INSENSITIVE and FATTR4_CASE_PRESERVING Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260429-case-sensitivity-v12-14-8057123bebe0@oracle.com> References: <20260429-case-sensitivity-v12-0-8057123bebe0@oracle.com> In-Reply-To: <20260429-case-sensitivity-v12-0-8057123bebe0@oracle.com> To: Al Viro , Christian Brauner , Jan Kara Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-nfs@vger.kernel.org, linux-api@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, hirofumi@mail.parknet.co.jp, linkinjeon@kernel.org, sj1557.seo@samsung.com, yuezhang.mo@sony.com, almaz.alexandrovich@paragon-software.com, slava@dubeyko.com, glaubitz@physik.fu-berlin.de, frank.li@vivo.com, tytso@mit.edu, adilger.kernel@dilger.ca, cem@kernel.org, sfrench@samba.org, pc@manguebit.org, ronniesahlberg@gmail.com, sprasad@microsoft.com, trondmy@kernel.org, anna@kernel.org, jaegeuk@kernel.org, chao@kernel.org, hansg@kernel.org, senozhatsky@chromium.org, Chuck Lever , Roland Mainz X-Mailer: b4 0.16-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=4565; i=chuck.lever@oracle.com; h=from:subject:message-id; bh=t5OVike6DqWKusHjBgnWfNA/dcYYQEQa2zmnV+SeSqI=; b=owEBbQKS/ZANAwAKATNqszNvZn+XAcsmYgBp8kjdIBXdCBmDR6d5dnOoVHD6fOHXtFo8oV4rz fR7xAvMR/KJAjMEAAEKAB0WIQQosuWwEobfJDzyPv4zarMzb2Z/lwUCafJI3QAKCRAzarMzb2Z/ l6ALEACL+Ov0mGavDpGUnvHe2gm16M0/DvQ0s1tfhkdOEhbsBHjCIN5c2uf0Ei664VfP3ebcHvA WQL1ofIJvkdofugvUJVD8JjhmfOIXaUrCjhGgUvbax9Q+wXHD4AMOUXyotOVK2qXDakRlMZClcR CdpEyS7gmLYJp5CdTzliIgcanmlkEPvoD7RzJOnF5aPHiMlCtla6BewGUaFVgiwH6SV8vElvkX3 +XafxJbEuI1V+ZTjvtRJpwbf42zoGxOPCHyu5DRvW41TLcP7GmQnYAgTZF53blvjRwCwnPbYbNk wfsOQCOcxKpr583GOCAMuuRr98dbVuE+Hio9ahBHX7quJYMYXquQMpXTyPklrfpZ9yH0xyO6zbR 9OOuifs9t5IWOPbMQ3WqG42uVr+vY5mg2s1seVnhAHC9IlqeRMwzekaiAmZQK82wmHhXDvtnzJz fMPjjTN5uIkv6HmdO9WeshtlJZbKXicyTPs5/m5FqhoW+TWR75Ox4WYejk8mf7Vj9YGIR0Tfita h2cfcJhkTGGOlXS7Yaw5a9Wmo7y06zMomFWxhEtn9I0SIajxo4qip6TRilEfv2r1ViYH+8svLAH YxATX8i9wIeQj6DgLUx/oButwK7+JklxJOEIgRLoJe/aQpqUoRYmAqs6T69HUTnSfMNp/olKXYO HlPsqHPFbsHc+ng== X-Developer-Key: i=chuck.lever@oracle.com; a=openpgp; fpr=28B2E5B01286DF243CF23EFE336AB3336F667F97 From: Chuck Lever NFSD currently provides NFSv4 clients with hard-coded responses indicating all exported filesystems are case-sensitive and case-preserving. This is incorrect for case-insensitive filesystems and ext4 directories with casefold enabled. Query the underlying filesystem's actual case sensitivity via nfsd_get_case_info() and return accurate values to clients. This supports per-directory settings for filesystems that allow mixing case-sensitive and case-insensitive directories within an export. Reviewed-by: Roland Mainz Signed-off-by: Chuck Lever --- fs/nfsd/nfs4xdr.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 49 insertions(+), 3 deletions(-) diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 2a0946c630e1..d77304692e11 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -3158,6 +3158,8 @@ struct nfsd4_fattr_args { u32 rdattr_err; bool contextsupport; bool ignore_crossmnt; + bool case_insensitive; + bool case_preserving; }; typedef __be32(*nfsd4_enc_attr)(struct xdr_stream *xdr, @@ -3356,6 +3358,33 @@ static __be32 nfsd4_encode_fattr4_acl(struct xdr_stream *xdr, return nfs_ok; } +static __be32 nfsd4_encode_fattr4_case_insensitive(struct xdr_stream *xdr, + const struct nfsd4_fattr_args *args) +{ + return nfsd4_encode_bool(xdr, args->case_insensitive); +} + +static __be32 nfsd4_encode_fattr4_case_preserving(struct xdr_stream *xdr, + const struct nfsd4_fattr_args *args) +{ + return nfsd4_encode_bool(xdr, args->case_preserving); +} + +static __be32 nfsd4_encode_fattr4_homogeneous(struct xdr_stream *xdr, + const struct nfsd4_fattr_args *args) +{ + /* + * Casefold-capable filesystems (e.g. ext4 or f2fs with the + * casefold feature) attach a Unicode encoding at mount time + * but apply case folding per directory. The per-file-system + * case_insensitive and case_preserving values can therefore + * legitimately differ across objects that share the same fsid. + * Report FATTR4_HOMOGENEOUS = FALSE on such filesystems to + * keep that variation consistent with RFC 8881 Section 5.8.2.16. + */ + return nfsd4_encode_bool(xdr, !sb_has_encoding(args->dentry->d_sb)); +} + static __be32 nfsd4_encode_fattr4_filehandle(struct xdr_stream *xdr, const struct nfsd4_fattr_args *args) { @@ -3748,8 +3777,8 @@ static const nfsd4_enc_attr nfsd4_enc_fattr4_encode_ops[] = { [FATTR4_ACLSUPPORT] = nfsd4_encode_fattr4_aclsupport, [FATTR4_ARCHIVE] = nfsd4_encode_fattr4__noop, [FATTR4_CANSETTIME] = nfsd4_encode_fattr4__true, - [FATTR4_CASE_INSENSITIVE] = nfsd4_encode_fattr4__false, - [FATTR4_CASE_PRESERVING] = nfsd4_encode_fattr4__true, + [FATTR4_CASE_INSENSITIVE] = nfsd4_encode_fattr4_case_insensitive, + [FATTR4_CASE_PRESERVING] = nfsd4_encode_fattr4_case_preserving, [FATTR4_CHOWN_RESTRICTED] = nfsd4_encode_fattr4__true, [FATTR4_FILEHANDLE] = nfsd4_encode_fattr4_filehandle, [FATTR4_FILEID] = nfsd4_encode_fattr4_fileid, @@ -3758,7 +3787,7 @@ static const nfsd4_enc_attr nfsd4_enc_fattr4_encode_ops[] = { [FATTR4_FILES_TOTAL] = nfsd4_encode_fattr4_files_total, [FATTR4_FS_LOCATIONS] = nfsd4_encode_fattr4_fs_locations, [FATTR4_HIDDEN] = nfsd4_encode_fattr4__noop, - [FATTR4_HOMOGENEOUS] = nfsd4_encode_fattr4__true, + [FATTR4_HOMOGENEOUS] = nfsd4_encode_fattr4_homogeneous, [FATTR4_MAXFILESIZE] = nfsd4_encode_fattr4_maxfilesize, [FATTR4_MAXLINK] = nfsd4_encode_fattr4_maxlink, [FATTR4_MAXNAME] = nfsd4_encode_fattr4_maxname, @@ -3968,6 +3997,23 @@ nfsd4_encode_fattr4(struct svc_rqst *rqstp, struct xdr_stream *xdr, args.fhp = tempfh; } else args.fhp = fhp; + if (attrmask[0] & (FATTR4_WORD0_CASE_INSENSITIVE | + FATTR4_WORD0_CASE_PRESERVING)) { + err = nfsd_get_case_info(dentry, &args.case_insensitive, + &args.case_preserving); + /* + * SUPPORTED_ATTRS unconditionally advertises both + * bits, and the Linux client treats an absent + * CASE_PRESERVING in a GETATTR reply as false. When + * the filesystem does not expose case state, + * nfsd_get_case_info() fills POSIX defaults + * (case-sensitive, case-preserving) and returns + * -EOPNOTSUPP; encode those defaults so the reply + * agrees with what the server claims to support. + */ + if (err && err != -EOPNOTSUPP) + goto out_nfserr; + } if (attrmask[0] & FATTR4_WORD0_ACL) { err = nfsd4_get_nfs4_acl(rqstp, dentry, &args.acl); -- 2.53.0