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/position_host_v2.py

@@ -0,0 +1,108 @@
+"""position_host_v2.py <pid> -- Position is 72 bytes (not 96).
+For each Position vt hit:
+  - Detect array adjacency at stride 72.
+  - Look at offsets -56..-4 for host vtables.
+  - Bucket: (array-element, ppv-wrapper, host-embedded, solo).
+"""
+import ctypes, ctypes.wintypes as wt, struct, sys
+from collections import Counter
+
+POSITION_VT = 0x00797910
+SIZEOF_POSITION = 72   # vt + objcell_id + Frame(64)
+ACMIN, ACMAX = 0x00400000, 0x00900000
+
+PROCESS_VM_READ = 0x10
+PROCESS_QUERY_INFORMATION = 0x400
+
+class MBI(ctypes.Structure):
+    _fields_ = [('BaseAddress', ctypes.c_void_p),
+                ('AllocationBase', ctypes.c_void_p),
+                ('AllocationProtect', wt.DWORD),
+                ('PartitionId', wt.WORD),
+                ('RegionSize', ctypes.c_size_t),
+                ('State', wt.DWORD),
+                ('Protect', wt.DWORD),
+                ('Type', wt.DWORD)]
+
+k = ctypes.windll.kernel32
+k.OpenProcess.argtypes = [wt.DWORD, wt.BOOL, wt.DWORD]; k.OpenProcess.restype = wt.HANDLE
+k.CloseHandle.argtypes = [wt.HANDLE]; k.CloseHandle.restype = wt.BOOL
+k.ReadProcessMemory.argtypes = [wt.HANDLE, wt.LPCVOID, wt.LPVOID, ctypes.c_size_t,
+                                ctypes.POINTER(ctypes.c_size_t)]
+k.ReadProcessMemory.restype = wt.BOOL
+k.VirtualQueryEx.argtypes = [wt.HANDLE, ctypes.c_void_p, ctypes.POINTER(MBI), ctypes.c_size_t]
+k.VirtualQueryEx.restype = ctypes.c_size_t
+
+
+def classify(data, off, pos_set):
+    # array adjacency at stride 72
+    if off >= SIZEOF_POSITION and (off - SIZEOF_POSITION) in pos_set:
+        return ('array_inner', None)
+    if (off + SIZEOF_POSITION) in pos_set:
+        return ('array_head', None)
+    # Look for any acclient code-range vtable in -56..-4
+    candidate_offs = list(range(-56, 0, 4))
+    found = None
+    for d in candidate_offs:
+        if off + d < 0: continue
+        v = struct.unpack_from("<I", data, off + d)[0]
+        if ACMIN <= v <= ACMAX:
+            # check vtable plausibility — slot 0 should point to a code-page
+            # we can't read .text from this script easily — keep just the vtable
+            found = (d, v)
+            break
+    if found:
+        return ('embedded', found)
+    return ('solo', None)
+
+
+def scan(pid):
+    h = k.OpenProcess(PROCESS_VM_READ | PROCESS_QUERY_INFORMATION, False, pid)
+    if not h:
+        print(f"OpenProcess err={ctypes.get_last_error()}"); return 1
+
+    buckets = Counter()
+    host_at_off = Counter()       # (off, vtable) -> count
+    total = 0
+
+    mbi = MBI(); addr = 0
+    while k.VirtualQueryEx(h, addr, ctypes.byref(mbi), ctypes.sizeof(mbi)):
+        pr = mbi.Protect & 0xff
+        if (mbi.State == 0x1000 and mbi.Type == 0x20000
+                and pr in (0x04, 0x40)):
+            buf = (ctypes.c_ubyte * mbi.RegionSize)()
+            sz = ctypes.c_size_t(0)
+            if k.ReadProcessMemory(h, mbi.BaseAddress, buf, mbi.RegionSize, ctypes.byref(sz)):
+                data = bytes(buf[:sz.value])
+                end = (len(data) // 4) * 4
+                pos_offs = []
+                for off in range(0, end, 4):
+                    if struct.unpack_from("<I", data, off)[0] == POSITION_VT:
+                        pos_offs.append(off)
+                pos_set = set(pos_offs)
+                for off in pos_offs:
+                    total += 1
+                    bucket, ev = classify(data, off, pos_set)
+                    buckets[bucket] += 1
+                    if bucket == 'embedded':
+                        host_at_off[ev] += 1
+        addr = (mbi.BaseAddress or 0) + mbi.RegionSize
+        if addr >= 0x80000000:
+            break
+
+    print(f"PID {pid}: {total} Position instances")
+    for b, n in buckets.most_common():
+        pct = 100.0 * n / total
+        print(f"  {b:>15}: {n:>7}  ({pct:5.1f}%)")
+    print()
+    print("Top (offset, host-vtable) combos for 'embedded' bucket:")
+    for (off, vt), n in host_at_off.most_common(20):
+        pct = 100.0 * n / total
+        print(f"  off={off:+4d}  vt=0x{vt:08x}  count={n:>6}  ({pct:.2f}%)")
+
+    k.CloseHandle(h)
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(scan(int(sys.argv[1])))