On 1/23/25 3:43 PM, Jeff Layton wrote:
On Thu, 2025-01-23 at 14:52 -0500, cel@xxxxxxxxxx wrote:From: Chuck Lever <chuck.lever@xxxxxxxxxx> RFC 8881 Section 18.25.4 paragraph 5 tells us that the server should return NFS4ERR_FILE_OPEN only if the target object is an opened file. This suggests that returning this status when removing a directory will confuse NFS clients. This is a version-specific issue; nfsd_proc_remove/rmdir() and nfsd3_proc_remove/rmdir() already return nfserr_access as appropriate. Unfortunately there is no quick way for nfsd4_remove() to determine whether the target object is a file or not, so the check is done in to nfsd_unlink() for now. Reported-by: Trond Myklebust <trondmy@xxxxxxxxxxxxxxx> Fixes: 466e16f0920f ("nfsd: check for EBUSY from vfs_rmdir/vfs_unink.") Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> --- fs/nfsd/vfs.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 2d8e27c225f9..3ead7fb3bf04 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1931,9 +1931,17 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen, return err; }-/*- * Unlink a file or directory - * N.B. After this call fhp needs an fh_put +/** + * nfsd_unlink - remove a directory entry + * @rqstp: RPC transaction context + * @fhp: the file handle of the parent directory to be modified + * @type: enforced file type of the object to be removed + * @fname: the name of directory entry to be removed + * @flen: length of @fname in octets + * + * After this call fhp needs an fh_put. + * + * Returns a generic NFS status code in network byte-order. */ __be32 nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, @@ -2007,10 +2015,14 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, fh_drop_write(fhp); out_nfserr: if (host_err == -EBUSY) { - /* name is mounted-on. There is no perfect - * error status. + /* + * See RFC 8881 Section 18.25.4 para 4: NFSv4 REMOVE + * distinguishes between reg file and dir. */ - err = nfserr_file_open; + if (type != S_IFDIR)Should that be "if (type == S_ISREG)" instead? What if the inode is a named pipe or device file? I'm not sure you can ever get EBUSY with those, but in case you can, what's the right error in those cases?
Check out nfsd_unlink()'s callers to see what they pass as the type parameter. Unfortunately we have to compare against S_IFDIR here.
+ err = nfserr_file_open; + else + err = nfserr_acces; } out: return err != nfs_ok ? err : nfserrno(host_err);
-- Chuck Lever
