Commit 3b60984e authored by Chuck Lever's avatar Chuck Lever
Browse files

NFSD: Return NFS4ERR_FILE_OPEN only when renaming over an open file 



RFC 8881 Section 18.26.4 paragraphs 1 - 3 tell us that RENAME should
return NFS4ERR_FILE_OPEN only when the target object is a file that
is currently open. If the target is a directory, some other status
must be returned.

Generally I expect that a delegation recall will be triggered in
some of these circumstances. In other cases, the VFS might return
-EBUSY for other reasons, and NFSD has to ensure that errno does
not leak to clients as a status code that is not permitted by spec.

There are some error flows where the target dentry hasn't been
found yet. The default value for @type therefore is S_IFDIR to return
an alternate status code in those cases.

Reviewed-by: default avatarJeff Layton <jlayton@kernel.org>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 370345b4

fs/nfsd/vfs.c

+29 −4
Original line number Diff line number Diff line
@@ -1794,9 +1794,19 @@ nfsd_has_cached_files(struct dentry *dentry) 
	return ret;

}



/*

 * Rename a file

 * N.B. After this call _both_ ffhp and tfhp need an fh_put

/**

 * nfsd_rename - rename a directory entry

 * @rqstp: RPC transaction context

 * @ffhp: the file handle of parent directory containing the entry to be renamed

 * @fname: the filename of directory entry to be renamed

 * @flen: the length of @fname in octets

 * @tfhp: the file handle of parent directory to contain the renamed entry

 * @tname: the filename of the new entry

 * @tlen: the length of @tlen in octets

 *

 * After this call _both_ ffhp and tfhp need an fh_put.

 *

 * Returns a generic NFS status code in network byte-order.

 */

__be32

nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
@@ -1804,6 +1814,7 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, 
{

	struct dentry	*fdentry, *tdentry, *odentry, *ndentry, *trap;

	struct inode	*fdir, *tdir;

	int		type = S_IFDIR;

	__be32		err;

	int		host_err;

	bool		close_cached = false;
@@ -1861,11 +1872,14 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, 
	host_err = -EINVAL;

	if (odentry == trap)

		goto out_dput_old;

	type = d_inode(odentry)->i_mode & S_IFMT;



	ndentry = lookup_one_len(tname, tdentry, tlen);

	host_err = PTR_ERR(ndentry);

	if (IS_ERR(ndentry))

		goto out_dput_old;

	if (d_inode(ndentry))

		type = d_inode(ndentry)->i_mode & S_IFMT;

	host_err = -ENOTEMPTY;

	if (ndentry == trap)

		goto out_dput_new;
@@ -1903,7 +1917,18 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, 
 out_dput_old:

	dput(odentry);

 out_nfserr:

	if (host_err == -EBUSY) {

		/*

		 * See RFC 8881 Section 18.26.4 para 1-3: NFSv4 RENAME

		 * wants a status unique to the object type.

		 */

		if (type != S_IFDIR)

			err = nfserr_file_open;

		else

			err = nfserr_acces;

	} else {

		err = nfserrno(host_err);

	}



	if (!close_cached) {

		fh_fill_post_attrs(ffhp);