Docker-compose: no access to Wordpress files - docker

Question

I just tried to host a Wordpress instance using docker on a freshly install Ubuntu machine. My problem is I am not allowed to modify the Wordpress files or create new files - I recieve Permission denied. I am certain that I am missing something - Can somebody explain to me what I am doing wrong?
Here are the commands I've used:
wget -qO- https://get.docker.com/ | sh
sudo usermod -aG docker $(whoami)
*restart*
sudo apt-get -y install python-pip
sudo pip install docker-compose
nano docker-compose.yml (See further down for the content of the file)
docker-compose up
The content of docker-compose.yml
wordpress:
image: wordpress
links:
- wordpress_db:mysql
ports:
- 80:80
volumes:
- ./src:/var/www/html
wordpress_db:
image: mariadb
environment:
MYSQL_ROOT_PASSWORD: ****
ports:
- 3306:3306
phpmyadmin:
image: corbinu/docker-phpmyadmin
links:
- wordpress_db:mysql
ports:
- 8181:80
environment:
MYSQL_USERNAME: root
MYSQL_ROOT_PASSWORD: ****
Here is the contents of ls -la inside the src dir:
total 196
drwxr-xr-x 5 www-data www-data 4096 apr 26 16:24 .
drwxrwxr-x 3 philip philip 4096 apr 26 16:14 ..
-rw-r--r-- 1 www-data www-data 234 apr 26 16:14 .htaccess
-rw-r--r-- 1 www-data www-data 418 sep 25 2013 index.php
-rw-r--r-- 1 www-data www-data 19935 mar 5 21:14 license.txt
-rw-r--r-- 1 www-data www-data 7358 dec 6 19:49 readme.html
-rw-r--r-- 1 www-data www-data 5032 jan 28 04:35 wp-activate.php
drwxr-xr-x 9 www-data www-data 4096 apr 12 20:46 wp-admin
-rw-r--r-- 1 www-data www-data 364 dec 19 12:20 wp-blog-header.php
-rw-r--r-- 1 www-data www-data 1476 jan 30 22:56 wp-comments-post.php
-rw-r--r-- 1 www-data www-data 3233 apr 26 16:24 wp-config.php
-rw-r--r-- 1 www-data www-data 2853 apr 26 16:24 wp-config-sample.php
drwxr-xr-x 4 www-data www-data 4096 apr 26 16:33 wp-content
-rw-r--r-- 1 www-data www-data 3286 maj 24 2015 wp-cron.php
drwxr-xr-x 16 www-data www-data 12288 apr 12 20:46 wp-includes
-rw-r--r-- 1 www-data www-data 2380 okt 25 2013 wp-links-opml.php
-rw-r--r-- 1 www-data www-data 3316 nov 6 00:59 wp-load.php
-rw-r--r-- 1 www-data www-data 33837 mar 6 04:06 wp-login.php
-rw-r--r-- 1 www-data www-data 7887 okt 6 2015 wp-mail.php
-rw-r--r-- 1 www-data www-data 13106 feb 17 23:58 wp-settings.php
-rw-r--r-- 1 www-data www-data 28624 jan 28 04:51 wp-signup.php
-rw-r--r-- 1 www-data www-data 4035 nov 30 2014 wp-trackback.php
-rw-r--r-- 1 www-data www-data 3061 okt 3 2015 xmlrpc.php