| Message ID | 20250123195242.1378601-4-cel@kernel.org (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Chuck Lever |
| Headers | show |
| Series | Avoid returning NFS4ERR_FILE_OPEN when not appropriate | expand |
On Thu, Jan 23, 2025 at 8:52 PM <cel@kernel.org> wrote: > > From: Chuck Lever <chuck.lever@oracle.com> > > 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. > > Signed-off-by: Chuck Lever <chuck.lever@oracle.com> > --- > fs/nfsd/vfs.c | 30 ++++++++++++++++++++++++++---- > 1 file changed, 26 insertions(+), 4 deletions(-) > > diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c > index 3ead7fb3bf04..5cfb5eb54c23 100644 > --- a/fs/nfsd/vfs.c > +++ b/fs/nfsd/vfs.c > @@ -1795,9 +1795,19 @@ 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, > @@ -1805,6 +1815,7 @@ 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; > @@ -1867,6 +1878,7 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, > host_err = PTR_ERR(ndentry); > if (IS_ERR(ndentry)) > goto out_dput_old; > + type = d_inode(ndentry)->i_mode & S_IFMT; > host_err = -ENOTEMPTY; > if (ndentry == trap) > goto out_dput_new; > @@ -1904,7 +1916,17 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, > out_dput_old: > dput(odentry); > out_nfserr: > - err = nfserrno(host_err); > + if (host_err == -EBUSY) { > + /* > + * See RFC 8881 Section 18.26.4 para 1-3: NFSv4 RENAME > + * status distinguishes between reg file and dir. > + */ > + if (type != S_IFDIR) Maybe (type == S_IFREG) here as well? > + err = nfserr_file_open; > + else > + err = nfserr_acces; > + } else > + err = nfserrno(host_err); > if {} else ; is a code smell with high potential for human misreading of code. Thanks, Amir.
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 3ead7fb3bf04..5cfb5eb54c23 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1795,9 +1795,19 @@ 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, @@ -1805,6 +1815,7 @@ 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; @@ -1867,6 +1878,7 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, host_err = PTR_ERR(ndentry); if (IS_ERR(ndentry)) goto out_dput_old; + type = d_inode(ndentry)->i_mode & S_IFMT; host_err = -ENOTEMPTY; if (ndentry == trap) goto out_dput_new; @@ -1904,7 +1916,17 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, out_dput_old: dput(odentry); out_nfserr: - err = nfserrno(host_err); + if (host_err == -EBUSY) { + /* + * See RFC 8881 Section 18.26.4 para 1-3: NFSv4 RENAME + * status distinguishes between reg file and dir. + */ + 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);