Nginx 502 Bad Gateway

2046#0: *12 directory index of "/var/www/" is forbidden, client: 192.168.0.39, server: localhost, request: "GET / HTTP/1.1", host: "192.168.0.31"
2046#0: *12 open() "/var/www/favicon.ico" failed (2: No such file or directory), client: 192.168.0.39, server: localhost, request: "GET /favicon.ico$
2046#0: *12 connect() to unix:/tmp/php-fpm.sock failed (2: No such file or directory) while connecting to upstream, client: 192.168.0.39, server: loc$
2046#0: *12 client 192.168.0.39 closed keepalive connection

user nginx nginx;
worker_processes 1;

error_log /var/log/nginx/error_log info;

events {
worker_connections 1024;
use epoll;
}

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

client_header_timeout 10m;
client_body_timeout 10m;
send_timeout 10m;

connection_pool_size 256;
client_header_buffer_size 1k;
large_client_header_buffers 4 2k;
request_pool_size 4k;

gzip on;
gzip_min_length 1100;
gzip_buffers 4 8k;
gzip_types text/plain;

output_buffers 1 32k;
postpone_output 1460;

sendfile on;
tcp_nopush on;
tcp_nodelay on;

keepalive_timeout 75 20;

ignore_invalid_headers on;

index index.php index.html;

server {
listen 80;
server_name localhost;

access_log /var/log/nginx/localhost.access_log;
error_log /var/log/nginx/localhost.error_log info;

root /var/www/;
include php-fpm.conf;
}
}