Nginx 跨域请求被阻止

Question

我的网页出现此错误：“跨源请求被阻止：同源策略不允许读取远程资源https://www.cdn-example.com（原因：缺少 CORS 标头‘Access-Control-Allow-Origin’）。”

我有 Nginx，这是我的配置： /etc/nginx/nginx.conf

user www-data;
worker_processes auto;
pid /run/nginx.pid;
include /etc/nginx/modules-enabled/*.conf;

events {
    worker_connections 768;
    # multi_accept on;
}

http {

    ##
    # Basic Settings
    ##

    sendfile on;
    tcp_nopush on;
    tcp_nodelay on;
    keepalive_timeout 65;
    types_hash_max_size 2048;
    # server_tokens off;

    # server_names_hash_bucket_size 64;
    # server_name_in_redirect off;

    include /etc/nginx/mime.types;
    default_type application/octet-stream;

    ##
    # SSL Settings
    ##

    ssl_protocols TLSv1 TLSv1.1 TLSv1.2; # Dropping SSLv3, ref: POODLE
    ssl_prefer_server_ciphers on;

    ##
    # Logging Settings
    ##

    access_log /var/log/nginx/access.log;
    error_log /var/log/nginx/error.log;

    ##
    # Gzip Settings
    ##

    gzip on;

    # gzip_vary on;
    # gzip_proxied any;
    # gzip_comp_level 6;
    # gzip_buffers 16 8k;
    # gzip_http_version 1.1;
    # gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;

    ##
    # Virtual Host Configs
    ##

    include /etc/nginx/conf.d/*.conf;
    include /etc/nginx/sites-enabled/*;
}

/etc/nginx/sites-enabled/default

server {
    listen 80;
    listen [::]:80;
    return 301 https://$host$request_uri;
}

server {
   # listen 443 default_server;
   # listen            [::]:443;
    listen 443 default_server;
    listen [::]:443;
    ssl on;
    ssl_certificate /etc/ssl/certs/pem-access.pem;
    ssl_certificate_key /etc/ssl/private/key-access.key;
    access_log            /var/log/nginx/nginx.access.log;
    error_log            /var/log/nginx/nginx.error.log;
    location / {
        add_header 'Access-Control-Allow-Origin' "https://www.cdn-example.com" always;
    }
}

Mi 原创网站是其他https://www.example.com