Check nil

Author: wchen-r7

modules/auxiliary/scanner/ftp/konica_ftp_traversal.rb

@@ -72,6 +72,11 @@ def run_host(target_host)
       # read the file data from the socket that we opened
       response_data = sock.read(1024)
 
+      unless response_data
+        print_error("#{file_path} not found")
+        return
+      end
+
       if response_data.length == 0 or ! (res =~ /^150/ )
         print_status("File (#{file_path})from #{peer} is empty...")
         return