From: Chuck Lever Date: Mon, 17 Nov 2025 16:00:49 +0000 (-0500) Subject: NFSD: Clear SECLABEL in the suppattr_exclcreat bitmap X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=27d17641cacfedd816789b75d342430f6b912bd2;p=thirdparty%2Fkernel%2Flinux.git NFSD: Clear SECLABEL in the suppattr_exclcreat bitmap >From RFC 8881: 5.8.1.14. Attribute 75: suppattr_exclcreat > The bit vector that would set all REQUIRED and RECOMMENDED > attributes that are supported by the EXCLUSIVE4_1 method of file > creation via the OPEN operation. The scope of this attribute > applies to all objects with a matching fsid. There's nothing in RFC 8881 that states that suppattr_exclcreat is or is not allowed to contain bits for attributes that are clear in the reported supported_attrs bitmask. But it doesn't make sense for an NFS server to indicate that it /doesn't/ implement an attribute, but then also indicate that clients /are/ allowed to set that attribute using OPEN(create) with EXCLUSIVE4_1. Ensure that the SECURITY_LABEL and ACL bits are not set in the suppattr_exclcreat bitmask when they are also not set in the supported_attrs bitmask. Fixes: 8c18f2052e75 ("nfsd41: SUPPATTR_EXCLCREAT attribute") Cc: stable@vger.kernel.org Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever --- diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 30ce5851fe4c..51ef97c25456 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -3375,6 +3375,11 @@ static __be32 nfsd4_encode_fattr4_suppattr_exclcreat(struct xdr_stream *xdr, u32 supp[3]; memcpy(supp, nfsd_suppattrs[resp->cstate.minorversion], sizeof(supp)); + if (!IS_POSIXACL(d_inode(args->dentry))) + supp[0] &= ~FATTR4_WORD0_ACL; + if (!args->contextsupport) + supp[2] &= ~FATTR4_WORD2_SECURITY_LABEL; + supp[0] &= NFSD_SUPPATTR_EXCLCREAT_WORD0; supp[1] &= NFSD_SUPPATTR_EXCLCREAT_WORD1; supp[2] &= NFSD_SUPPATTR_EXCLCREAT_WORD2;