[Bug]: SMB share with trailing dollar sign on 28.0.2 generates error during occ files:scan

⚠️ 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

During a file scan for a user having external smb storage with a dollar sign the following error happens:

Error during scan: Couldn't get xattr for smb://10.1.2.3/some.user$/: unknown error (13)
Exception during scan: Invalid request for / (ForbiddenException)
#0 /var/www/nextcloud/apps/files_external/lib/Lib/Storage/SMB.php(696): OCA\Files_External\Lib\Storage\SMB->getFileInfo()
#1 /var/www/nextcloud/lib/private/Files/Storage/Wrapper/Wrapper.php(224): OCA\Files_External\Lib\Storage\SMB->file_exists()
#2 /var/www/nextcloud/lib/private/Files/Utils/Scanner.php(263): OC\Files\Storage\Wrapper\Wrapper->file_exists()
#3 /var/www/nextcloud/apps/files/lib/Command/Scan.php(180): OC\Files\Utils\Scanner->scan()
#4 /var/www/nextcloud/apps/files/lib/Command/Scan.php(241): OCA\Files\Command\Scan->scanFiles()
#5 /var/www/nextcloud/3rdparty/symfony/console/Command/Command.php(298): OCA\Files\Command\Scan->execute()
#6 /var/www/nextcloud/core/Command/Base.php(177): Symfony\Component\Console\Command\Command->run()
#7 /var/www/nextcloud/3rdparty/symfony/console/Application.php(1040): OC\Core\Command\Base->run()
#8 /var/www/nextcloud/3rdparty/symfony/console/Application.php(301): Symfony\Component\Console\Application->doRunCommand()
#9 /var/www/nextcloud/3rdparty/symfony/console/Application.php(171): Symfony\Component\Console\Application->doRun()
#10 /var/www/nextcloud/lib/private/Console/Application.php(206): Symfony\Component\Console\Application->run()
#11 /var/www/nextcloud/console.php(100): OC\Console\Application->run()
#12 /var/www/nextcloud/occ(11): require_once('...')
#13 {main}

Steps to reproduce

1. Run php occ files:scan --all
2. Wait
3. Error shows up

Expected behavior

No error

Installation method

Community Manual installation with Archive

Nextcloud Server version

28

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.2

Web server

Apache (supported)

Database engine version

MariaDB

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

None

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

{
    "system": {
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "mysql",
        "version": "28.0.2.5",
        "overwrite.cli.url": "https:\/\/cloud",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "force_language": "de",
        "force_locale": "de_DE",
        "defaultapp": "files",
        "knowledgebaseenabled": false,
        "allow_user_to_change_display_name": false,
        "log_type": "file",
        "loglevel": 3,
        "logfile": "\/var\/log\/nextcloud\/nextcloud.log",
        "log_rotate_size": 104857600,
        "skeletondirectory": "",
        "memcache.local": "\\OC\\Memcache\\Redis",
        "filelocking.enabled": "true",
        "memcache.distributed": "\\OC\\Memcache\\Redis",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 6379,
            "timeout": 0,
            "dbindex": 0
        },
        "maintenance": false,
        "lost_password_link": "disabled",
        "ldapIgnoreNamingRules": false,
        "ldapProviderFactory": "OCA\\User_LDAP\\LDAPProviderFactory",
        "onlyoffice": {
            "verify_peer_off": true
        },
        "trusted_proxies": "***REMOVED SENSITIVE VALUE***",
        "overwriteprotocol": "https",
        "overwritewebroot": "\/\/",
        "overwriteconaddr": "***REMOVED SENSITIVE VALUE***",
        "csrf.disabled": true,
        "updater.release.channel": "stable",
        "theme": "",
        "twofactor_enforced": "true",
        "twofactor_enforced_groups": [],
        "twofactor_enforced_excluded_groups": [],
        "mail_smtpmode": "smtp",
        "mail_smtpsecure": "ssl",
        "mail_sendmailmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauthtype": "LOGIN",
        "mail_smtpauth": 1,
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "465",
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "default_phone_region": "DE",
        "app_install_overwrite": [
            "bbb",
            "twofactor_admin",
            "spreed"
        ],
        "trashbin_retention_obligation": "auto, 31",
        "maintenance_window_start": 1
    }
}

List of activated Apps

Enabled:
  - app_api: 2.0.4
  - bbb: 2.5.0
  - bruteforcesettings: 2.8.0
  - calendar: 4.6.4
  - circles: 28.0.0-dev
  - cloud_federation_api: 1.11.0
  - contacts: 5.5.1
  - contactsinteraction: 1.9.0
  - dashboard: 7.8.0
  - dav: 1.29.1
  - deck: 1.12.1
  - drawio: 3.0.2
  - eidlogin: 1.0.15
  - federatedfilesharing: 1.18.0
  - files: 2.0.0
  - files_external: 1.20.0
  - files_pdfviewer: 2.9.0
  - files_reminders: 1.1.0
  - files_sharing: 1.20.0
  - files_trashbin: 1.18.0
  - files_versions: 1.21.0
  - forms: 4.1.0
  - integration_zammad: 2.0.6
  - logreader: 2.13.0
  - lookup_server_connector: 1.16.0
  - mail: 3.5.5
  - notifications: 2.16.0
  - oauth2: 1.16.3
  - ownpad: 0.10.0
  - photos: 2.4.0
  - polls: 6.0.1
  - privacy: 1.12.0
  - provisioning_api: 1.18.0
  - related_resources: 1.3.0
  - richdocuments: 8.3.1
  - serverinfo: 1.18.0
  - settings: 1.10.1
  - smb_test: 0.3.8
  - spreed: 18.0.3
  - stt_helper: 1.1.0
  - stt_whisper: 1.0.8
  - text: 3.9.1
  - theming: 2.3.0
  - twofactor_admin: 4.4.0
  - twofactor_backupcodes: 1.17.0
  - twofactor_totp: 10.0.0-beta.2
  - updatenotification: 1.18.0
  - user_ldap: 1.19.0
  - user_status: 1.8.1
  - viewer: 2.2.0
  - weather_status: 1.8.0
  - workflowengine: 2.10.0
Disabled:
  - activity: 2.20.0 (installed 2.9.1)
  - admin_audit: 1.18.0
  - assistant: 1.0.3 (installed 1.0.3)
  - comments: 1.18.0 (installed 1.6.0)
  - context_chat: 1.0.0 (installed 1.0.0)
  - encryption: 2.16.0
  - federation: 1.18.0 (installed 1.6.0)
  - files_linkeditor: 1.1.16 (installed 1.1.16)
  - files_markdown: 2.4.1 (installed 2.4.1)
  - files_rightclick: 0.15.1 (installed 1.6.0)
  - files_texteditor: 2.15.1 (installed 2.15.1)
  - firstrunwizard: 2.17.0 (installed 2.5.0)
  - nextcloud_announcements: 1.17.0 (installed 1.5.0)
  - onlyoffice: 8.2.4 (installed 8.2.4)
  - openotp_sign: 1.5.2 (installed 1.5.2)
  - password_policy: 1.18.0 (installed 1.6.0)
  - recommendations: 2.0.0 (installed 0.4.0)
  - sharebymail: 1.18.0 (installed 1.6.0)
  - support: 1.11.0 (installed 1.0.0)
  - survey_client: 1.16.0 (installed 1.4.0)
  - suspicious_login: 6.0.0
  - systemtags: 1.18.0 (installed 1.6.0)

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

No response

Start in apps/files_external/lib/Lib/Storage/SMB.php around line 696, then trace the call from occ files:scan through Scanner and the SMB storage implementation. Reproduce with an external SMB share whose name ends in $, and consider the issue resolved when the scan completes without the xattr or ForbiddenException errors.