Initial commit — leak-hunt project complete

Five bugs identified and patched in retail Asheron's Call client:
- v3b: palette refcount over-increment (3-byte NOP at two sites)
- v5: RenderSurface PurgeResource no-op stub (vtable slot 2 thunk)
- v11: two dangling-pointer crash guards (NULL-check + reorder)
- v14: CEnvCell::Destroy ClipPlaneList leak (18-byte JMP to cleanup thunk)
- v22: unpacker stale-pointer SEH guard (whole-function __try/__except)

All five ship in leakfix.dll (117 KB, SHA d282f23c…) which is loaded
by acclient.exe at process start via PE import table patching by
tools/install_leakfix.py.

Controlled 15-client fleet soak: unpatched control died at 26h with
palette exhaustion; all 14 patched clients survived past that point
and reached ≥5-day uptime.

Residual ~15 MB/h growth traced to d3d9.dll's internal slab allocator
(260KB surface backing buffers retained after Release). See REPORT.md
§10 for the full investigation; conclusion is that it's unfixable from
outside d3d9.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

tools/patch_v6_test.py

@@ -0,0 +1,143 @@
+"""patch_v6_test.py <pid> [--revert]
+
+EXPERIMENTAL v6: NOP the IsVisible guard in
+UIElement_ItemList::UpdateEmptySlots at EoR 0x004e4390.
+
+Mechanism:
+  The function starts:
+    sub esp, 0x10
+    push esi
+    mov esi, ecx               ; this = ecx
+    call IsVisible             ; → al
+    test al, al
+    jz  end_of_function        ; <-- 6 bytes at 0x004e439d, NOP these
+    ...
+
+  Replacing the 6-byte `0F 84 F3 01 00 00` with six NOPs makes the
+  function continue regardless of visibility. The trim loop inside
+  then runs and deletes WAITING-state items.
+
+Why this fixes the leak:
+  Every container open/close triggers ItemList_Flush, which calls
+  Clear_UIItem + SetState(WAITING) on every cell, then calls
+  UpdateEmptySlots. UpdateEmptySlots currently bails when invisible
+  (which is exactly when Flush is called on close). NOPing the
+  visibility check lets the trim loop run, calling InternalDeleteItem
+  on each WAITING cell.
+
+Risks:
+  After visibility-check NOP, the function still has a second guard
+  (GetAttribute_Int(0x10000015) == -1). If GetAttribute misbehaves
+  on invisible widgets, behavior could be unexpected. For inventory
+  lists this should be fine (the attribute is set at ctor).
+"""
+import argparse
+import ctypes
+import ctypes.wintypes as wt
+import sys
+
+
+PATCH_SITE_VA   = 0x004e439d
+ORIGINAL_BYTES  = bytes([0x0f, 0x84, 0xf3, 0x01, 0x00, 0x00])   # jz +0x1f3
+PATCHED_BYTES   = bytes([0x90, 0x90, 0x90, 0x90, 0x90, 0x90])   # 6x nop
+
+
+PROCESS_VM_READ           = 0x0010
+PROCESS_VM_WRITE          = 0x0020
+PROCESS_VM_OPERATION      = 0x0008
+PROCESS_QUERY_INFORMATION = 0x0400
+PAGE_EXECUTE_READWRITE    = 0x40
+PAGE_READWRITE            = 0x04
+
+
+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
+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
+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
+VirtualProtectEx   = k32.VirtualProtectEx
+VirtualProtectEx.argtypes = [wt.HANDLE, wt.LPVOID, ctypes.c_size_t, wt.DWORD,
+                             ctypes.POINTER(wt.DWORD)]
+VirtualProtectEx.restype = wt.BOOL
+
+
+def read_bytes(h, addr, n):
+    buf = (ctypes.c_ubyte * n)()
+    sz = ctypes.c_size_t(0)
+    if not ReadProcessMemory(h, addr, buf, n, ctypes.byref(sz)):
+        raise OSError(f"read 0x{addr:08x} err={ctypes.get_last_error()}")
+    return bytes(buf[:sz.value])
+
+
+def write_bytes(h, addr, data):
+    old_prot = wt.DWORD(0)
+    if not VirtualProtectEx(h, addr, len(data), PAGE_EXECUTE_READWRITE, ctypes.byref(old_prot)):
+        raise OSError(f"VirtualProtectEx 0x{addr:08x} err={ctypes.get_last_error()}")
+    sz = ctypes.c_size_t(0)
+    ok = WriteProcessMemory(h, addr, data, len(data), ctypes.byref(sz))
+    err = ctypes.get_last_error() if not ok else 0
+    restored = wt.DWORD(0)
+    VirtualProtectEx(h, addr, len(data), old_prot.value, ctypes.byref(restored))
+    if not ok:
+        raise OSError(f"write 0x{addr:08x} err={err}")
+
+
+def main():
+    ap = argparse.ArgumentParser()
+    ap.add_argument("pid", type=int)
+    ap.add_argument("--revert", action="store_true",
+                    help="restore original JZ instruction")
+    args = ap.parse_args()
+
+    h = OpenProcess(
+        PROCESS_VM_READ | PROCESS_VM_WRITE | PROCESS_VM_OPERATION | PROCESS_QUERY_INFORMATION,
+        False, args.pid,
+    )
+    if not h:
+        print(f"OpenProcess({args.pid}) err={ctypes.get_last_error()}")
+        sys.exit(2)
+
+    cur = read_bytes(h, PATCH_SITE_VA, 6)
+    print(f"PID {args.pid}")
+    print(f"  patch site @ 0x{PATCH_SITE_VA:08x} current: {cur.hex()}")
+
+    if args.revert:
+        if cur == ORIGINAL_BYTES:
+            print("  already original — nothing to revert")
+            CloseHandle(h); return
+        if cur != PATCHED_BYTES:
+            print(f"  UNEXPECTED — current bytes don't match either original or patched")
+            print(f"  expected original {ORIGINAL_BYTES.hex()} or patched {PATCHED_BYTES.hex()}")
+            CloseHandle(h); sys.exit(3)
+        write_bytes(h, PATCH_SITE_VA, ORIGINAL_BYTES)
+        after = read_bytes(h, PATCH_SITE_VA, 6)
+        print(f"  reverted; bytes now: {after.hex()}")
+        CloseHandle(h); return
+
+    if cur == PATCHED_BYTES:
+        print("  already patched — nothing to do")
+        CloseHandle(h); return
+    if cur != ORIGINAL_BYTES:
+        print(f"  UNEXPECTED — current bytes {cur.hex()} don't match expected original {ORIGINAL_BYTES.hex()}")
+        CloseHandle(h); sys.exit(4)
+
+    write_bytes(h, PATCH_SITE_VA, PATCHED_BYTES)
+    after = read_bytes(h, PATCH_SITE_VA, 6)
+    print(f"  patched; bytes now: {after.hex()}")
+    if after != PATCHED_BYTES:
+        print("  MISMATCH — write didn't take")
+        CloseHandle(h); sys.exit(5)
+    print("  OK")
+    CloseHandle(h)
+
+
+if __name__ == "__main__":
+    main()