Force at least one unique stack frame per fuzzer #95
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This change is an attempt to address the behavior found at google/oss-fuzz#8389 where two distinct bugs were accidentally deduplicated into the same bug report. One of the reasons for this is that the stack traces between the two bugs were almost the same with only very minor differences. My hope is that by forcing a unique stack frame per fuzzer this will be less likely since there is guaranteed to be at least one stack frame per fuzz target which is unique with this change. While I was here I wrapped up the generated function by the `fuzz_target!` macro in a `const _: () = { ... }` to avoid adding this new `run` function in to the normal module's namespace and accidentally causing name collisions (e.g. if fuzz targets already have functions named `run`)
fitzgen
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The `libfuzzer-sys` update in bytecodealliance#5068 included some changes to the `fuzz_target!` macro which caused a bare `run` function to be shadowed by the macro-defined `run` function (changed in rust-fuzz/libfuzzer#95) which meant that some of our fuzz targets were infinite looping or stack overflowing as the same function was called indefinitely. This renames the top-level `run` function to something else in the meantime.
alexcrichton
added a commit
to alexcrichton/wasmtime
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Oct 24, 2022
The `libfuzzer-sys` update in bytecodealliance#5068 included some changes to the `fuzz_target!` macro which caused a bare `run` function to be shadowed by the macro-defined `run` function (changed in rust-fuzz/libfuzzer#95) which meant that some of our fuzz targets were infinite looping or stack overflowing as the same function was called indefinitely. This renames the top-level `run` function to something else in the meantime.
alexcrichton
added a commit
to bytecodealliance/wasmtime
that referenced
this pull request
Oct 24, 2022
The `libfuzzer-sys` update in #5068 included some changes to the `fuzz_target!` macro which caused a bare `run` function to be shadowed by the macro-defined `run` function (changed in rust-fuzz/libfuzzer#95) which meant that some of our fuzz targets were infinite looping or stack overflowing as the same function was called indefinitely. This renames the top-level `run` function to something else in the meantime.
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This change is an attempt to address the behavior found at
google/oss-fuzz#8389 where two distinct bugs were accidentally
deduplicated into the same bug report. One of the reasons for this is
that the stack traces between the two bugs were almost the same with
only very minor differences. My hope is that by forcing a unique stack
frame per fuzzer this will be less likely since there is guaranteed to
be at least one stack frame per fuzz target which is unique with this
change.
While I was here I wrapped up the generated function by the
fuzz_target!macro in aconst _: () = { ... }to avoid adding thisnew
runfunction in to the normal module's namespace and accidentallycausing name collisions (e.g. if fuzz targets already have functions
named
run)