Merge pull request #12123 from aredondo/master

Add regression test for IpSpoofAttackError issue

Closes #10780

actionpack/test/dispatch/request_test.rb

@@ -93,6 +93,14 @@ def url_for(options = {})
     assert_equal '1.1.1.1', request.remote_ip
   end
 
+  test "remote ip spoof protection ignores private addresses" do
+    request = stub_request 'HTTP_X_FORWARDED_FOR' => '172.17.19.51',
+                           'HTTP_CLIENT_IP'       => '172.17.19.51',
+                           'REMOTE_ADDR'          => '1.1.1.1',
+                           'HTTP_X_BLUECOAT_VIA'  => 'de462e07a2db325e'
+    assert_equal '1.1.1.1', request.remote_ip
+  end
+
   test "remote ip v6" do
     request = stub_request 'REMOTE_ADDR' => '2001:0db8:85a3:0000:0000:8a2e:0370:7334'
     assert_equal '2001:0db8:85a3:0000:0000:8a2e:0370:7334', request.remote_ip