diff --git a/contrib/pg_upgrade/pg_upgrade.c b/contrib/pg_upgrade/pg_upgrade.c
new file mode 100644
index e329dc3..0b6fb61
*** a/contrib/pg_upgrade/pg_upgrade.c
--- b/contrib/pg_upgrade/pg_upgrade.c
*************** setup(char *argv0, bool live_check)
*** 171,176 ****
--- 171,178 ----
  	*last_dir_separator(exec_path) = '\0';
  	canonicalize_path(exec_path);
  	os_info.exec_path = pg_strdup(exec_path);
+ 
+ 	pg_putenv("PGAPPNAME", "binary-upgrade");
  }
  
  
diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c
new file mode 100644
index 8347f52..f359af2
*** a/src/backend/utils/init/postinit.c
--- b/src/backend/utils/init/postinit.c
*************** InitPostgres(const char *in_dbname, Oid 
*** 833,838 ****
--- 833,848 ----
  	if (MyProcPort != NULL)
  		process_startup_options(MyProcPort, am_superuser);
  
+ 	/*
+ 	 * Binary upgrades only allow the proper application name
+ 	 */
+ 	if (IsBinaryUpgrade && strcmp(application_name, "binary-upgrade") != 0)
+ 	{
+ 		ereport(FATAL,
+ 				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ 			 errmsg("the application name must be \"binary-upgrade\" to connect in binary upgrade mode")));
+ 	}
+ 
  	/* Process pg_db_role_setting options */
  	process_settings(MyDatabaseId, GetSessionUserId());