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ci: CFL migrates to Ubuntu 24.04 + MSan fix#94

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xyephy wants to merge 5 commits intostratum-mining:masterfrom
xyephy:2026/04/cfl-msan-fix
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ci: CFL migrates to Ubuntu 24.04 + MSan fix#94
xyephy wants to merge 5 commits intostratum-mining:masterfrom
xyephy:2026/04/cfl-msan-fix

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@xyephy xyephy commented Apr 20, 2026

Supersedes #75.

The new base image's glibc 2.39 exposes a libFuzzer + MSan bug:
argc/argv arrive poisoned at LLVMFuzzerInitialize, so the fuzz
binary aborts before any target runs. Fix: __msan_unpoison at entry.

Also drops the two remaining forks (run-fuzzers image, and the
migrate-to-ubuntu-24-04 branch ref on google/clusterfuzzlite actions).

Validation on xyephy/sv2-tp:2025/12/cfl-ubuntu-24-msan-test:

  • CFL PR fuzzing green across address/undefined/memory: run 24675431211
  • Coverage: build, corpus replay, llvm-cov HTML generation all worked

Sjors and others added 5 commits April 20, 2026 23:39
Expose fuzz_targets.txt in $OUT so run-fuzzers sees targets.

Assisted-by: GitHub Copilot
Assisted-by: OpenAI GPT-5.1-Codex-Max
It should no longer be needed to use a fork.
libFuzzer forwards argc/argv from glibc. On glibc >= 2.39 MSan
doesn't unpoison them, causing a spurious uninit read in SetArgs.
Upstream :ubuntu-24-04-v1 ships llvm-symbolizer at /usr/local/bin.
@xyephy xyephy mentioned this pull request Apr 20, 2026
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2 participants