Fix ret2csu with PIE binaries (Gallopsled#2158)

* fix indentation

* Allow ret2csu to find non-pie binaries

* ret2csu: fix detection logic

---------

Co-authored-by: peace-maker <[email protected]>
Co-authored-by: Arusekk <[email protected]>

Author: 3 people

pwnlib/rop/rop.py

@@ -1544,23 +1544,18 @@ def ret2csu(self, edi=Padding('edi'), rsi=Padding('rsi'),
         # Prioritise non-PIE binaries so we can use _fini
         exes = (elf for elf in self.elfs if not elf.library and elf.bits == 64)
 
-        nonpie = csu = None
+        csu = None
         for elf in exes:
-            if not elf.pie:
-                if '__libc_csu_init' in elf.symbols:
-                    break
-                nonpie = elf
-            elif '__libc_csu_init' in elf.symbols:
+            if '__libc_csu_init' in elf.symbols:
                 csu = elf
+                if not elf.pie:
+                    break
+
+        if csu:
+            elf = csu
         else:
             log.error('No non-library binaries in [elfs]')
 
-        if elf.pie:
-            if nonpie:
-                elf = nonpie
-            elif csu:
-                elf = csu
-
         from .ret2csu import ret2csu
         ret2csu(self, elf, edi, rsi, rdx, rbx, rbp, r12, r13, r14, r15, call)