From ad6277c0ee163eadef3b327e76d9600437644cb2 Mon Sep 17 00:00:00 2001
From: JoYo <>
Date: Sun, 24 Feb 2019 06:34:26 +0000
Subject: [PATCH] capstone isn't disassembling the whole block, dumb heuristics
 for growth

---
 sins/mutation.py | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/sins/mutation.py b/sins/mutation.py
index e5f15b4..22cf192 100644
--- a/sins/mutation.py
+++ b/sins/mutation.py
@@ -55,13 +55,18 @@ def generation(queue: Queue, shellcode: bytes):
 
 
 def growth(*, shellcode: bytes, length: int) -> bytes:
-    for mnemonic, op_str in disasm(shellcode):
-        if mnemonic == 'nop':
-            return bytes(shellcode)
-
     if length <= len(shellcode):
         return bytes(shellcode)
 
+    opcodes = disasm(shellcode)
+
+    if len(shellcode) > len(opcodes) * 8:
+        return bytes(shellcode)
+
+    for mnemonic, op_str in opcodes:
+        if mnemonic == 'nop':
+            return bytes(shellcode)
+
     shellcode = bytearray(shellcode)
     shellcode += b'\x90'