Break FD hacks

[ngc92]

use pipes instead of unlinked files to guarantee unidirectional transfers

[Copilot]

Pull request overview

This PR replaces the previous “unlinked temp file” result channel used by the isolated benchmark subprocess with inherited pipes, aiming to enforce unidirectional result transfer and reduce FD-based tampering opportunities.

Changes:

• Switch benchmark result transport from a temp file to a one-way pipe, and add a subprocess timeout.
• Add a “signature” mechanism intended to authenticate result output from the C++ layer.
• Update C++ benchmark manager to write results via FILE* (from an FD) and emit the signature marker; update exploit scripts to target pipe-based transport.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 12 comments.

Show a summary per file

File	Description
python/pygpubench/init.py	Uses pipes for results + adds timeout + signature verification parsing
csrc/manager.h	Changes manager constructor to accept FDs; stores output as FILE* and signature string
csrc/manager.cpp	Uses fdopen/fprintf/fflush; reads signature from FD and emits it in output
csrc/binding.cpp	Updates nanobind binding signature to pass FDs into BenchmarkManager
exploits/submission_thread_fd.py	Adjusts exploit’s FD search heuristic to look for FIFOs instead of unlinked files
exploits/submission_fd_overwrite.py	Rewrites exploit narrative/logic to target writable FIFO FDs

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 10 comments.

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 6 changed files in this pull request and generated 4 comments.

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