Handle stack frame offset for x86 stack vars (#35)

mahaloz · Jun 2, 2022 · 5798361 · 5798361
1 parent a3093f3
commit 5798361
Showing 1 changed file with 12 additions and 2 deletions.
diff --git a/decompilers/d2d_binja/server.py b/decompilers/d2d_binja/server.py
@@ -1,6 +1,6 @@
 from xmlrpc.server import SimpleXMLRPCServer, SimpleXMLRPCRequestHandler
 
-from binaryninja import SymbolType
+from binaryninja import SymbolType, EntryRegisterValue
 from binaryninja.binaryview import BinaryDataNotification
 
 #
@@ -102,10 +102,20 @@ def function_data(self, addr: int):
 
         func = funcs[0]
 
+        # get stack frame offset for x86
+        frame_offset = 0
+        if self.bv.arch.name == 'x86_64':
+            frame_offset -= self.bv.arch.address_size
+        elif self.bv.arch.name == 'x86':
+            # handle inconsistent stack frame offsets
+            current_frame = func.get_reg_value_at(addr, 'ebp')
+            if current_frame.type != EntryRegisterValue.type:
+                frame_offset = current_frame.value
+
         # get stack vars
         stack_vars = {}
         for stack_var in func.stack_layout:
-            offset = abs(stack_var.storage)
+            offset = frame_offset - stack_var.storage
             stack_vars[str(offset)] = {
                 "name": stack_var.name,
                 "type": str(stack_var.type)