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_palette_v1.py

@@ -0,0 +1,106 @@
+"""patch_palette_v1.py <pid> [--revert]
+
+Apply (or revert) the Palette leak fix to a running acclient.exe.
+
+Mechanism:
+  Overwrite Palette's primary vtable slot +0x2c (which is the
+  DBObj::ReleaseSubObjects no-op stub) to point at Palette's existing
+  PurgeResource function (slot +0x3c) instead. This causes
+  DBOCache::FreeObject's ReleaseSubObjects call to actually free the
+  ARGB buffer when the palette goes to the freelist.
+
+  Target: EoR vtable 0x007caa08, slot +0x2c
+  Replace value: 0x004154a0  (no-op stub, returns 1)
+  With value:    0x0053ecf0  (PurgeResource — frees +0x40 buffer)
+
+Safety:
+  - Idempotent: only patches if current value matches the no-op stub
+  - Revert via --revert flag
+  - Saves before-image to backup
+  - The dtor at 0x0053f0d0 guards against NULL — no double-free risk
+"""
+import ctypes, ctypes.wintypes as wt, sys, struct
+
+VT_PRIMARY    = 0x007caa08
+SLOT_OFFSET   = 0x2c
+TARGET_ADDR   = VT_PRIMARY + SLOT_OFFSET   # 0x007caa34
+EXPECTED_VAL  = 0x004154a0                  # no-op ReleaseSubObjects stub
+PATCHED_VAL   = 0x0053ecf0                  # Palette::PurgeResource
+
+PROCESS_VM_READ           = 0x0010
+PROCESS_VM_WRITE          = 0x0020
+PROCESS_VM_OPERATION      = 0x0008
+PROCESS_QUERY_INFORMATION = 0x0400
+
+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
+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():
+    if len(sys.argv) < 2:
+        print("usage: patch_palette_v1.py <pid> [--revert]"); sys.exit(1)
+    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)
+
+    # Read current value
+    cur = ctypes.c_uint(0); sz = ctypes.c_size_t(0)
+    if not ReadProcessMemory(h, TARGET_ADDR, ctypes.byref(cur), 4, ctypes.byref(sz)):
+        print(f"read failed: err={ctypes.get_last_error()}"); CloseHandle(h); sys.exit(3)
+    print(f"PID {pid}  slot @ 0x{TARGET_ADDR:08x} current: 0x{cur.value:08x}")
+
+    target = EXPECTED_VAL if revert else PATCHED_VAL
+    expect_before = PATCHED_VAL if revert else EXPECTED_VAL
+
+    if cur.value == target:
+        print(f"  already {'reverted' if revert else 'patched'} — nothing to do")
+        CloseHandle(h); return
+
+    if cur.value != expect_before:
+        print(f"  UNEXPECTED current value (expected 0x{expect_before:08x}) — aborting to avoid corruption")
+        CloseHandle(h); sys.exit(4)
+
+    # Make page writable
+    old_prot = wt.DWORD(0)
+    if not VirtualProtectEx(h, TARGET_ADDR, 4, PAGE_READWRITE, ctypes.byref(old_prot)):
+        print(f"VirtualProtectEx failed: err={ctypes.get_last_error()}"); CloseHandle(h); sys.exit(5)
+    print(f"  old protect: 0x{old_prot.value:x}")
+
+    # Write new value
+    new = ctypes.c_uint(target)
+    if not WriteProcessMemory(h, TARGET_ADDR, ctypes.byref(new), 4, ctypes.byref(sz)):
+        print(f"write failed: err={ctypes.get_last_error()}"); CloseHandle(h); sys.exit(6)
+
+    # Restore original protection
+    restored = wt.DWORD(0)
+    VirtualProtectEx(h, TARGET_ADDR, 4, old_prot.value, ctypes.byref(restored))
+
+    # Verify
+    ReadProcessMemory(h, TARGET_ADDR, ctypes.byref(cur), 4, ctypes.byref(sz))
+    print(f"  new value:   0x{cur.value:08x}  ({'reverted' if revert else 'patched'} successfully)")
+    CloseHandle(h)
+
+
+if __name__ == "__main__":
+    main()