"""patch_palette_v3.py <pid> [--revert]

v3 patch: NOP the extra refcount increment in Palette::makeModifiedPalette
(EoR FUN_0053efe0). This stops the +1 over-increment that leaves every
new "modified palette" at refcount=2 instead of refcount=1.

Background:
  FUN_0053efe0 = Palette::makeModifiedPalette():
    new(0x48); Palette::Palette(this, 0x800); this->refcount++; return;
  The "this->refcount++" makes the returned palette have refcount=2.
  After caller's single Release, refcount=1, and the palette becomes
  unreachable (m_pMaintainer is NULL — no cache reference) but alive.

  56,664 leaked palettes in dump_9156 are all this shape: rc=1,
  m_pMaintainer=0, m_numLinks=0.

Target bytes: 0x0053effe (3 bytes inside FUN_0053efe0)
  Original:  ff 40 24   ; inc dword [eax+0x24]   ; refcount++
  Patched:   90 90 90   ; nop nop nop

The 2013 build has the same +1 pattern at 0x0053e29e — leak likely
exists there too, just less noticeable.

Risk: some caller may assume refcount=2 and release twice; after this
patch, the second release would crash on already-freed memory. Test on
one client and watch closely.
"""
import ctypes, ctypes.wintypes as wt, sys

TARGET_ADDR    = 0x0053effe
ORIGINAL_BYTES = bytes([0xff, 0x40, 0x24])
PATCHED_BYTES  = bytes([0x90, 0x90, 0x90])

PROCESS_VM_READ           = 0x0010
PROCESS_VM_WRITE          = 0x0020
PROCESS_VM_OPERATION      = 0x0008
PROCESS_QUERY_INFORMATION = 0x0400
PAGE_EXECUTE_READWRITE    = 0x40

k32 = ctypes.windll.kernel32
OpenProcess        = k32.OpenProcess
OpenProcess.argtypes = [wt.DWORD, wt.BOOL, wt.DWORD]; OpenProcess.restype = wt.HANDLE
CloseHandle        = k32.CloseHandle
CloseHandle.argtypes = [wt.HANDLE]; CloseHandle.restype = wt.BOOL
ReadProcessMemory  = k32.ReadProcessMemory
ReadProcessMemory.argtypes = [wt.HANDLE, wt.LPCVOID, wt.LPVOID, ctypes.c_size_t,
                              ctypes.POINTER(ctypes.c_size_t)]
ReadProcessMemory.restype = wt.BOOL
WriteProcessMemory = k32.WriteProcessMemory
WriteProcessMemory.argtypes = [wt.HANDLE, wt.LPVOID, wt.LPCVOID, ctypes.c_size_t,
                               ctypes.POINTER(ctypes.c_size_t)]
WriteProcessMemory.restype = wt.BOOL
VirtualProtectEx   = k32.VirtualProtectEx
VirtualProtectEx.argtypes = [wt.HANDLE, wt.LPVOID, ctypes.c_size_t,
                             wt.DWORD, ctypes.POINTER(wt.DWORD)]
VirtualProtectEx.restype = wt.BOOL


def main():
    pid    = int(sys.argv[1])
    revert = "--revert" in sys.argv

    h = OpenProcess(PROCESS_VM_READ|PROCESS_VM_WRITE|PROCESS_VM_OPERATION|PROCESS_QUERY_INFORMATION,
                    False, pid)
    if not h:
        print(f"OpenProcess({pid}) failed: err={ctypes.get_last_error()}"); sys.exit(2)

    cur = (ctypes.c_ubyte * 3)(); sz = ctypes.c_size_t(0)
    if not ReadProcessMemory(h, TARGET_ADDR, cur, 3, ctypes.byref(sz)):
        print(f"read failed: err={ctypes.get_last_error()}"); CloseHandle(h); sys.exit(3)
    cur_b = bytes(cur)
    print(f"PID {pid}  bytes @ 0x{TARGET_ADDR:08x}: {' '.join(f'{b:02x}' for b in cur_b)}")

    target = ORIGINAL_BYTES if revert else PATCHED_BYTES
    expect_before = PATCHED_BYTES if revert else ORIGINAL_BYTES

    if cur_b == target:
        print(f"  already {'reverted' if revert else 'patched'}"); CloseHandle(h); return
    if cur_b != expect_before:
        print(f"  UNEXPECTED current bytes (wanted {' '.join(f'{b:02x}' for b in expect_before)}) — aborting")
        CloseHandle(h); sys.exit(4)

    old_prot = wt.DWORD(0)
    if not VirtualProtectEx(h, TARGET_ADDR, 3, PAGE_EXECUTE_READWRITE, ctypes.byref(old_prot)):
        print(f"VirtualProtectEx failed: err={ctypes.get_last_error()}"); CloseHandle(h); sys.exit(5)
    new = (ctypes.c_ubyte * 3)(*target)
    if not WriteProcessMemory(h, TARGET_ADDR, new, 3, ctypes.byref(sz)):
        print(f"write failed: err={ctypes.get_last_error()}"); CloseHandle(h); sys.exit(6)
    restored = wt.DWORD(0)
    VirtualProtectEx(h, TARGET_ADDR, 3, old_prot.value, ctypes.byref(restored))

    ReadProcessMemory(h, TARGET_ADDR, cur, 3, ctypes.byref(sz))
    print(f"  new bytes:   {' '.join(f'{b:02x}' for b in bytes(cur))}  ({'reverted' if revert else 'patched'})")
    CloseHandle(h)


if __name__ == "__main__":
    main()