Replace the stub_success registration of NtDeviceIoControlFile at
exports.rs:90 with a real handler for FsCtlCodes 0x70000 (drive
geometry) and 0x74004 (partition info), mirroring xenia-canary
xboxkrnl_io.cc:645-678 + null_device.{h,cc}. The 16-byte 0x74004
response with cache_size=0xFF000 at OUT+8 is the gate that lets
sub_824ABD88 return SUCCESS and sub_824A9710 reach the priv-11
XexCheckExecutablePrivilege site identified by KRNBUG-AUDIT-007.
Stack args 9-10 (OutputBuffer, OutputBufferLength) read from the
caller's parameter save area at [sp+0x54] / [sp+0x5C] per the Xbox
360 PowerPC EABI (linkage area sp+0..sp+8, 8-quadword spill area
sp+0x14..sp+0x54, then stack args every 8 bytes). First HLE export
in the codebase to need 9+ args.
Cascade vs. KRNBUG-AUDIT-007 prediction (5/8 held):
- XexCheckExecutablePrivilege count 1 → 2 (priv=0xA + priv=0xB) ✓
- XamTaskSchedule count 0 → 1 ✓
- canary-only exports 7 → 3 (audit predicted ≤3) ✓
- 0x15e0 semaphore signal_attempts 0 → 1 (bonus)
- 0x100c worker spawn DID NOT fire (still UNCREATED) ✗
- 0x1004 signal_attempts unchanged ✗
- Worker spawn count unchanged at 19 ✗
Tests: 592 → 594. Lockstep deterministic at -n 100M (run1 ≡ run2 ≡
run3, byte-identical). instructions=100000010 → 100000019, imports
407417 → 987524 (+2.4×). swaps=2 draws=0 plateau persists.
sylpheed_n50m golden re-baselined instructions=50000004→50000003,
imports=407362→407255. sylpheed_n2m unchanged.
Still canary-only after this fix: ExTerminateThread,
KeReleaseSemaphore, XamUserReadProfileSettings. The next downstream
gate is somewhere past XamTaskSchedule's completion path.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
a1a7265f29