I was playing around with a working Laravel 4 installation and moved everything into a sub folder. Then I decided to not do that and I moved it all back (all via the command
Spent a whole day for solving this and this command simply solved my problem.
If your permissions are 777 for Laravel App folder and you still get this error, it's because SEliux has blocked it. You can easily unblock your application's folder using this command:
su -c "chcon -R -h -t httpd_sys_script_rw_t /usr/share/nginx/YOUR_LARAVEL_APP/"
That's it!
BTW never disable SElinux: http://stopdisablingselinux.com/