Server: Internal Server Error when `config_is_read_only` is set and config is not writable by www-data

[leonklingele]

Steps to reproduce

1. Add 'config_is_read_only' => true, to your config.php
2. chown -R root: /path/to/nextcloud/config/

Expected behaviour

Nextcloud should work fine

Actual behaviour

Nextcloud doesn't work fine, shows Internal Server Error page, yet doesn't log anything.

Server configuration

Operating system:
Linux nextcloud 4.19.0-5-amd64 #1 SMP Debian 4.19.37-5 (2019-06-19) x86_64 GNU/Linux

Web server:
nginx version: nginx/1.14.2

Database:
mariadb-server 1:10.3.15-1

PHP version:
php-fpm 2:7.3+69

Nextcloud version: (see Nextcloud admin page)
Nextcloud 15.0.8

Updated from an older Nextcloud/ownCloud or fresh install:
Fresh install

Where did you install Nextcloud from:
Release tarball

Web server error log:

[..]
2019/07/14 16:54:47 [error] 150#150: *2086 FastCGI sent in stderr: "PHP message: PHP Warning:  fileperms(): stat failed for /var/www/nextcloud/data/nextcloud.log in /var/www/nextcloud/lib/private/Log/File.php on line 140PHP message: {"reqId":"5lHfVz3djClauspgcb7a","level":3,"time":"2019-07-14T14:54:47+00:00","remoteAddr":"fd42:6345:e3f8:de3e:216:3eff:fef8:baa9","user":"--","app":"PHP","method":"GET","url":"\/core\/img\/manifest.json","message":"touch(): Utime failed: Permission denied at \/var\/www\/nextcloud\/lib\/private\/Config.php#240","userAgent":"Mozilla\/5.0 (X11; U; Linux i686) AppleWebKit\/537.36 (KHTML, like Gecko) Chrome\/71.0.3578.84 Safari\/537.36","version":""}PHP message: PHP Warning:  fileperms(): stat failed for /var/www/nextcloud/data/nextcloud.log in /var/www/nextcloud/lib/private/Log/File.php on line 140PHP message: {"reqId":"5lHfVz3djClauspgcb7a","level":3,"time":"2019-07-14T14:54:47+00:00","remoteAddr":"fd42:6345:e3f8:de3e:216:3eff:fef8:baa9","user":"--","app":"PHP","method":"GET","url":"\/core\/img\/manifest.json","message":"fopen(\/var\/www\/nextcloud\/config\/config.php): failed to open stream: Permission denied at \/var\/www\/nextcloud\/lib\/private\/Config.php#241","userAgent":"Mozilla\/5.0 (X11; U; Linux i686) AppleWebKit\/537.36 (KHTML, like Gecko) Chrome\/71.0.3578.84 Safari\/537.36","version":""}PHP message: PHP Warning:  fileperms(): stat failed for /var/www/nextcloud/data/nextcloud.log in /var/www/nextcloud/lib/private/Log/File.php on line 140PHP message: {"reqId":"5lHfVz3djClauspgcb7a","level":3,"time":"2019-07-14T14:54:47+00:00","remoteAddr":"fd42:6345:e3f8:de3e:216:3eff:fef8:baa9","user":"--","app":"PHP","method":"GET","url":"\/core\/img\/manifest.json","message":"chmod(): Operation not permitted at \/var\/www\/nextcloud\/lib\/private\/Config.php#244","userAgent":"Mozilla\/5.0 (X11; U; Linux i686) AppleWebKit\/537.36 (KHTML, like Gecko) Chrome\/71.0.3578.84 Safari\/537.36","version":""}PHP message: PHP Warning:  fileperms(): stat failed for /var/www/nextcloud/data/nextcloud.lo
[..]

[kesselb]

Mind to check the permission of the log file? Looks like it's not writeable.

[wiswedel]

Mind to check the permission of the log file? Looks like it's not writeable.

With chown on root it's not even readable for www-data. That's the problem here.

Try setfacl -m u:www-data:r config.php

[leonklingele]

Log file (/srv/nextcloud-data/nextcloud.log) is owned by www-data:
-rw-r----- 1 www-data www-data 3079618 Jul 15 23:40 nextcloud.log

The Nextcloud installation resides at /var/www/nextcloud, but the data directory lives under /srv/nextcloud-data. The relevant config.php excerpt:

  'datadirectory' => '/srv/nextcloud-data',

Might this be the problem here?

The whole Nextcloud installation directory is owned – recursively – by root (chown -R root: /var/www/nextcloud) whereas the data directory is owned – recursively – by www-data (chown -R www-data: /srv/nextcloud-data).

[kesselb]

fileperms(): stat failed for /var/www/nextcloud/data/nextcloud.log in /var/www/nextcloud/lib/private/Log/File.php on line 140

A) logfile in config points to another location
or
B) config file is not readable

[leonklingele]

Sorry for the trouble! @wiswedel was right, Nextcloud apparently made config.php world-un-readable.
Solved by chowning it to root:www-data:

-rw-r----- 1 root www-data 1632 Jul 15 23:43 config.php