Fix dangling suffix pointer in tracked library info#175
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`record_library_load()` stored the autodetected `suffix` pointer directly, unlike `libname` which is deep-copied. This is only safe when `suffix` is a static string literal, but `autodetect_symbol_suffix()` checks the caller-supplied `suffix_hint` first and returns that pointer when it matches. In the `LBT_DEFAULT_LIBS` path that hint is a stack buffer in `init()`, so `lbt_config.loaded_libs[i]->suffix` would dangle after `init()` returns and a later `lbt_get_config()` read would be a use-after-return (triggered by e.g. `LBT_DEFAULT_LIBS="libopenblas64.so!64_"`). Deep-copy the suffix in `record_library_load()` and free it in `clear_loaded_libraries()`, matching the existing handling of `libname`. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Problem
record_library_load()insrc/config.cstored the autodetectedsuffixpointer directly, unlikelibnamewhich is deep-copied:This is safe only if
suffixis always a static string literal. Butautodetect_symbol_suffix()checks the caller-suppliedsuffix_hintfirst and returns that pointer when it matches. In theLBT_DEFAULT_LIBScode path that hint is a stack buffer ininit(), solbt_config.loaded_libs[i]->suffixdangles onceinit()returns — a laterlbt_get_config()read of.suffixis a use-after-return.Reproducible with e.g.
LBT_DEFAULT_LIBS="libopenblas64.so!64_".Fix
Deep-copy the suffix in
record_library_load()and free it inclear_loaded_libraries(), mirroring the existinglibnamehandling.Notes