Wordpress upload directory set to root:root?

newbie

Wordpress by default stores uploaded media in monthly sub-directories of the uploads directory. Eg wp-content/uploads/2016/07/

On one of my sites, this directory's owner gets set to "root:root", which means that nothing can be uploaded to the directory via the web server.

Any ideas what might cause this behaviour? I can imagine a cron script creating this behaviour, but I don't see how Wordpress itself should be able to create a directory owned by root.

portofacil

The only explanation I can think of is your PHP-FPM pool with the wrong user.

If you use PHP 7.3, try looking at:

/etc/php/7.3/fpm/pool.d/www.conf

Look at the user key, it should be set to www-data, as well the group key.

Perhaps the lines below help you with finding something suspicious:

cd /etc/php
grep -e '^user =' * -r