can only write to root level of smb share

[Jochen]

I have a smb share with guest access set up on an OpenMediaVault box. From a Windows 10 PC I can read and write the whole folder tree of this share, without password. On my Ubuntu box, I can do the same using smbclient, with null password.

However when using Gnome Files to access the share, choosing "anonymous" connect, I can only create or write files in the top level folder. Attempts to create or write to a subfolder result in a "Permission denied" error. Reading works across the whole folder tree.

The same happens when using the gio command line interface (here trying to create folders):
$ gio list smb://herkules.local/gvfs-bug
new1
$ gio mkdir smb://herkules.local/gvfs-bug/new2
$ gio list smb://herkules.local/gvfs-bug
new1
new2
$ gio mkdir smb://herkules.local/gvfs-bug/new2/new-sub
gio: smb://herkules.local/gvfs-bug/new2/new-sub: Permission denied
$

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: gvfs 1.36.1-0ubuntu1.3.3
ProcVersionSignature: Ubuntu 4.15.0-72.81-generic 4.15.18
Uname: Linux 4.15.0-72-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.9
Architecture: amd64
CurrentDesktop: GNOME
Date: Sun Dec 15 18:31:16 2019
InstallationDate: Installed on 2014-08-03 (1960 days ago)
InstallationMedia: Ubuntu-GNOME 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
SourcePackage: gvfs
UpgradeStatus: Upgraded to bionic on 2019-11-16 (29 days ago)