[Bug]: Shared Collectives cause "Path not found" when scannig files with "occ files:scan --all"

[arnowelzel]

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

When a Collective is shared with one or more users and you start a manual file scan using occ files:scan --all, this leads to the following error message for each user who is member of a Collective circle:

Path not found: /username

Where username is the name of the affected user.

Steps to reproduce

1. Create a collective
2. Share it with at least one other user
3. Run occ files:scan --all in a terminal

Expected behavior

occ files:scan --all runs without "Path not found" error messages

Installation method

Community Manual installation with Archive

Nextcloud Server version

28

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.1

Web server

Apache (supported)

Database engine version

MariaDB

Is this bug present after an update or on a fresh install?

Upgraded to a MAJOR version (ex. 22 to 23)

Are you using the Nextcloud Server Encryption module?

None

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

No response

List of activated Apps

No response

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

There is a workaround to fix this. In /server/lib/private/Files/Utils/Scanner.php the following code needs to be added, so Collectives mounts will be ignored during a file scan:

            // don't scan received local shares, these can be scanned when scanning the owner's storage
            if ($storage->instanceOfStorage(SharedStorage::class)
                || $storage->instanceOfStorage(CollectiveStorage::class)
            ) {
                continue;
            }

Also see https://help.nextcloud.com/t/occ-files-scan-outputs-path-not-found-for-some-users/177507/12 and

server/lib/private/Files/Utils/Scanner.php

Lines 237 to 239 in 5125c34

	// don't scan received local shares, these can be scanned when scanning the owner's storage
	if ($storage->instanceOfStorage(SharedStorage::class)) {
	continue;

[NL-TCH]

hi, any update on this?

[robertoschwald]

We’re affected as well. Using shared Collectives definitely triggers this bug for all other users the Collective is shared with.

[Pingger]

We are affected as well. Now 20% of the Accounts are affected. This seemingly prevents shares from these accounts to be moved to other folders and prevents deleting some files (which are already deleted on the disk) or creating some files (that already exist on disk).
The error prevents automatic fixing using the occ files:scan --all command and forces me to try to manually fix those errors directly in the database. For now I was only able to fix deletions with direct database interference. Shares, I have no idea how to begin with. Creating files, would involve too much for a single file to do manually.

The only workaround for now is deleted the entire account and recreate it. Then test scanning, if it still fails, repeat.

Affected Versions for me:
Nextcloud 31.0.5 with php 8.4.7