Adjusting exception handling

This commit adjusts the error handling to close the socket before
calling fail_with and adds specific exceptions to catch

modules/exploits/linux/http/tp_link_sc2020n_authenticated_telnet_injection.rb

@@ -128,9 +128,9 @@ class MetasploitModule < Msf::Exploit::Remote
           end
 
           handler(sock)
-        rescue
-          fail_with(Failure::Unknown, "Unknown error")
-          sock.close
+        rescue Rex::AddressInUse, ::Errno::ETIMEDOUT, Rex::HostUnreachable, Rex::ConnectionTimeout, Rex::ConnectionRefused, ::Timeout::Error, ::EOFError => e
+          sock.close if sock
+          fail_with(Failure::Unknown, e.message)
         end
     end