Land rapid7#9026, Fix cache invalidation bug in tab completion

Author: Brent Cook

lib/msf/ui/console/command_dispatcher/core.rb

@@ -139,10 +139,9 @@ def commands
   def initialize(driver)
     super
 
-    @dscache = {}
     @cache_payloads = nil
     @previous_module = nil
-    @module_name_stack = []
+    @previous_target = nil
     @history_limit = 100
   end
 
@@ -1627,12 +1626,6 @@ def cmd_set(*args)
     # Set the supplied name to the supplied value
     name  = args[0]
     value = args[1, args.length-1].join(' ')
-    if (name.upcase == "TARGET")
-      # Different targets can have different architectures and platforms
-      # so we need to rebuild the payload list whenever the target
-      # changes.
-      @cache_payloads = nil
-    end
 
     # If the driver indicates that the value is not valid, bust out.
     if (driver.on_variable_set(global, name, value) == false)
@@ -2288,11 +2281,16 @@ def option_values_dispatch(o, str, words)
   # Provide valid payload options for the current exploit
   #
   def option_values_payloads
-    return @cache_payloads if @cache_payloads
+    if @cache_payloads && active_module == @previous_module && active_module.target == @previous_target
+      return @cache_payloads
+    end
+
+    @previous_module = active_module
+    @previous_target = active_module.target
 
-    @cache_payloads = active_module.compatible_payloads.map { |refname, payload|
+    @cache_payloads = active_module.compatible_payloads.map do |refname, payload|
       refname
-    }
+    end
 
     @cache_payloads
   end

lib/msf/ui/console/command_dispatcher/modules.rb

@@ -48,7 +48,6 @@ def initialize(driver)
             super
 
             @dscache = {}
-            @cache_payloads = nil
             @previous_module = nil
             @module_name_stack = []
             @dangerzone_map = nil
@@ -645,7 +644,6 @@ def cmd_use(*args)
               active_module.datastore.update(@dscache[active_module.fullname])
             end
 
-            @cache_payloads = nil
             mod.init_ui(driver.input, driver.output)
 
             # Update the command prompt