luzer: print metrics only once - #93
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Проблема: На NixOS clang wrapper через hardening flags добавляет -D_FORTIFY_SOURCE=2 после пользовательских флагов, а -O2 — до. Когда CMake переопределяет -O2 на -O0 (для ASan/UBSan тестовых целей), -D_FORTIFY_SOURCE=2 остаётся, и glibc 2.40+ выдаёт ошибку: _FORTIFY_SOURCE requires compiling with optimization (-O). Исправление (в двух файлах): 1. luzer/CMakeLists.txt:46-52 — Добавлен -U_FORTIFY_SOURCE в общие флаги компиляции (belt-and-suspenders). 2. luzer/tests/CMakeLists.txt:218-219, 350-351 — Заменены -O0 на -O1 для ASan/UBSan тестовых целей (luac_asan, luac_ubsan, testlib_asan, testlib_ubsan). -O1 — минимальный рекомендуемый уровень оптимизации для санитайзеров. (cherry picked from commit 563e0a64f0e985562d48687652781a275382cba8)
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Hi, Sergey!
Thanks for the patch set!
Please consider my comments below.
For now tests are failing.
[PATCH 1/2] luzer: print metrics only once
Please consider my comments below.
It would be nice to add the test for fork mode.
[PATCH 2/2] cmake: FORTIFY_SOURCE
This patch looks like it is not ready for review. Commit message is in Russian.
Why -O0 is replaced with -O1?
| check_parent_or_child(void) | ||
| { | ||
| static pid_t saved_pid = -1; | ||
| static bool first_call = true; |
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It looks like this flag is redundant. Let's just use static saved_pid which is defined on library's initialization. Then we don't need this first_call plie.
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This reverts commit f80a574.
The function metrics_print() is called twice when `-fork`/`-jobs` are used. The reason is that `metrics_print()` is called from `__attribute__((destructor))`, and the destructor is executed in each forked process. When libFuzzer is run with the `-fork=N` or `-jobs=N` flags, it forks child processes. Each child process inherits the loaded shared library and its destructors. Fixes #89
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The function metrics_print() is called twice when
-fork/-jobsare used. The reason is thatmetrics_print()is called from__attribute__((destructor)), and the destructor is executed in each forked process. When libFuzzer is run with the-fork=Nor-jobs=Nflags, it forks child processes. Each child process inherits the loaded shared library and its destructors.The patch fixes that by adding a check to
metrics_print()to skip printing if all metrics are zero (so the parent process with zeros won't print, but the child process with data will).Fixes #89