Remove the error checking in dlllist, we need to be throwing exceptions and handling them.

volatility/framework/symbols/windows/extensions/__init__.py

@@ -13,12 +13,16 @@ class _ETHREAD(objects.Struct):
         """Return the EPROCESS that owns this thread"""
         return self.ThreadsProcess.dereference(kernel_layer)
 
+
 class _UNICODE_STRING(objects.Struct):
     @property
     def String(self):
-        if not self._context.memory[self.vol.layer_name].is_valid(self.Buffer):
-            return ""
-        return self.Buffer.dereference().cast("string", max_length = self.Length, errors = "replace", encoding = "utf16")
+        # We explicitly do *not* catch errors here, we allow an exception to be thrown
+        # (otherwise there's no way to determine anything went wrong)
+        # It's up to the user of this method to catch exceptions
+        return self.Buffer.dereference().cast("string", max_length = self.Length, errors = "replace",
+                                              encoding = "utf16")
+
 
 class _EPROCESS(objects.Struct):
     def add_process_layer(self, context, config_prefix = None, preferred_name = None):
@@ -66,14 +70,16 @@ class _EPROCESS(objects.Struct):
 
         proc_layer = self._context.memory[proc_layer_name]
         if not proc_layer.is_valid(self.Peb):
-            raise StopIteration 
+            raise StopIteration
 
         sym_table = self.vol.type_name.split("!")[0]
         peb = self._context.object("{}!_PEB".format(sym_table), layer_name = proc_layer_name, offset = self.Peb)
 
-        for entry in peb.Ldr.InLoadOrderModuleList.to_list("{}!_LDR_DATA_TABLE_ENTRY".format(sym_table), "InLoadOrderLinks"):
+        for entry in peb.Ldr.InLoadOrderModuleList.to_list("{}!_LDR_DATA_TABLE_ENTRY".format(sym_table),
+                                                           "InLoadOrderLinks"):
             yield entry
 
+
 class _LIST_ENTRY(objects.Struct, collections.abc.Iterable):
     def to_list(self, symbol_type, member, forward = True, sentinel = True, layer = None):
         """Returns an iterator of the entries in the list"""