- Add GetThreadContext/SetThreadContext overloads accepting Context32 so a
32-bit process on a native 32-bit OS can capture x86 thread context.
- DllInjector.InjectWithThreadHijack now selects the context API based on
both process bitness and OS bitness:
* 64-bit process -> native 64-bit context
* 32-bit process on 64-bit OS -> WOW64 context
* 32-bit process on 32-bit OS -> native x86 context
- ExternalReader now validates that the caller supplied
ProcessAccess.QueryInformation, and surfaces any IsWow64Process failure
instead of silently falling back to host bitness.
Tests: 207 passing, 4 skipped.
- AllocatedMemory.Read<T>/Write<T>/ReadBytes/WriteBytes now validate that
the requested byte range stays within the allocated block before calling
into the memory accessor.
- Patch.Apply/Remove temporarily changes the target page to read-write and
restores the original protection, mirroring the Detour behavior.
- MainThreadPump.WorkItem uses TrySetResult/TrySetException and swallows the
InvalidOperationException raised when a completion source is already
completed, preventing Dispose from failing during concurrent pump drainage.
Regression tests added for all three fixes.
Tests: 206 passing, 4 skipped.
Replace the two-attempt read with a single read sized to the smaller of:
- detourLength + 16 (the decoder's preferred window), and
- bytes remaining in the current page (so ReadProcessMemory does not fail whole read).
Reading only detourLength bytes could leave the instruction analyzer without enough
bytes to resolve a multi-byte instruction that crosses the splice point on
sparse prologues. Reading up to the page boundary gives the largest safe window.
Tests: 199 passing, 4 integration/interactive skipped.
Risk mitigation:
- redirect now falls back to reading the minimum required bytes (detourLength) if the full buffer (detourLength + 16) cannot be read due to page boundaries.
- First attempt: read detourLength + 16 bytes for the instruction analyzer (preferred).
- Second attempt: read only detourLength bytes if the first attempt fails (bare minimum).
- Throw only if both attempts fail.
This prevents crashes when function interception functions that sit at the very end of a committed page.
Tests: 199 passing, 4 integration/interactive skipped.
Bug fixes:
- InputSimulator: Pass correct button state (MK_LBUTTON/MK_RBUTTON) in wParam for button-down messages instead of 0.
- PeHeaderParser: ParseOptionalHeader now reads only the optional header, not section headers (fixes double-parse waste).
- EntryPoint: Removed useless isPe32Plus branch (AddressOfEntryPoint is at offset 16 in both PE32 and PE32+).
- RemoteWindow: Handle null foreground window case in Activate to avoid calling GetWindowThreadProcessId with HWND 0.
- RemotePointer: Remove dead null-conditional operators (encoding ??) since encoding is non-nullable.
Constants added:
- SystemMethods: MkLButton (0x0001) and MkRButton (0x0002) for mouse button state flags.
Tests: 199 passing, 4 integration/interactive skipped.
- Track whether transferred thread's original context was successfully restored.
- In the catch block, leak the remote allocation instead of freeing it if the thread was not restored; this prevents the target process from executing freed memory.
- Remove redundant 'op == 0x55' check in InstructionAnalyzer (already matched by (op & 0xF8) == 0x50).
- Simplify MemoryBase ReadString align-down expression to previousLen - (previousLen % nullLen).
- Change StubAllocator size parameter from nint to int for clarity (internal test seam).
Tests: 199 passing, 4 integration/interactive skipped.
- Add RemoteAllocator / RemoteReleaser internal test seams for string/struct scratch memory.
- Route all scratch allocation/freeing through the seams so tests can observe leaks.
- Fix inverted StubAllocator ownership: a caller-provided stub is now never freed by the executor.
- Rewrite Execute_releases_allocated_remote_memory_on_write_failure to fail pre-fix by tracking fake allocations through the seams.
- Update WriteFailingMemoryBase to carry a valid self-handle so the executor reaches the marshal/write path.
Tests: 198 passing, 4 integration/interactive skipped.
- MainThreadDispatcher: guard DispatchHook with try/catch so exceptions never escape to native caller; drain and fault pending work on Dispose; synchronize Execute/ExecuteAsync/Dispose against race/dispose.
- InstructionAnalyzer: require ModRM 0xEC for 0x83/0x81 sub-esp/rsp forms, rejecting unsafe RIP-relative or memory forms.
- PatternScannerCache: implement value equality on CacheKey so repeated scans actually hit cache.
- BackgroundTaskExecutor: add remote allocations to the free list immediately after VirtualAllocEx, before any write that could fail and leak.
- redirect: capture and restore original page protection in Apply/Remove instead of leaving target RWX.
- Regression tests for all six fixes.
Tests: 198 passing, 4 integration/interactive skipped.
The x64 frame math (0x20 + 8*stackArgs) and x86 arg buffer size grow with the
argument count. An absurdly large count could overflow int and produce a bogus
or negative frame. Add a MaxArguments (256) bound checked at the public entry —
far above any real calling convention — so the arithmetic stays in range. Add a
test asserting the cap is inclusive and count+1 throws.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
x64 call stub was ABI-broken: fixed 0x20 frame left rsp misaligned at the
inner call (callee entry rsp ≡ 0, ABI requires ≡ 8) and, for 5+ args, wrote
stack args over the return address. Compute frame K ≡ 8 (mod 16), K ≥
0x20 + 8*stackArgs, so the callee sees a 16-aligned stack and stack args land
above the shadow window. Load register args as full 64-bit imm64 (was imm32,
which truncated pointers > 4 GiB). BuildCallStub now takes nuint[]; x86 range-
checks each arg against uint.MaxValue instead of silently truncating.
MarshalCache conflated managed and unmanaged width in one Size field: the
blittable path needs Unsafe.SizeOf<T> (bool = 1) while the marshal path needs
Marshal.SizeOf<T> (inline ByValTStr/ByValArray expand past the managed
pointer). Add MarshalSize; MemoryBase picks per TypeRequiresMarshal at all four
IO sites. Prevents PtrToStructure/StructureToPtr from over-reading/overwriting
the pinned scratch buffer (heap corruption on write).
Extract shared RPM/WPM into RpmHelper: honor partial reads (dead Array.Resize
removed), consistent write-return semantics; InProcessReader now guards
MainModule like ExternalReader.
Tests: x64 frame-alignment property + inline-marshal round-trip added (both
fail against the pre-fix code); existing x64 byte-expectation tests updated to
the new frame. Build clean, 100/100 pass.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
kbe
