netboot: add fuzzer for TFTP network boot #786
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The name passed to parseNetbootinfo() is never modified, since all changes are made in a separate copy of the string, so mark the parameter as const. Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
Add a fuzzer for the netboot code, which focuses on its two public APIs: `parseNetbootinfo()` and `FetchNetbootimage()`. It stubs out the global PXE protocol handle to feed in bytes from libfuzzer into the netboot code, which means that this variable cannot be static when building the fuzzer. On top of that, the full_path static is allocated once and never freed, which is not problematic in normal operation, but triggers address sanitizer's leak detector, so expose it as well so that the harness can free the memory after each run. Add as well a dictionary with some magic strings and bytes that help get coverage faster. After a couple hours running and getting practically full coverage (verified with llvm-cov) the fuzzer luckily found no issues. Signed-off-by: Carlos López <carlos.lopezr4096@gmail.com>
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Add a fuzzer for the netboot code, which focuses on its two public APIs:
parseNetbootinfo()andFetchNetbootimage(). It stubs out the global PXE protocol handle to feed in bytes from libfuzzer into the netboot code, which means that this variable cannot be static when building the fuzzer. On top of that, thefull_pathstatic is allocated once and never freed, which is not problematic in normal operation, but triggers address sanitizer's leak detector, so expose it as well so that the harness can free the memory after each run.Add as well a dictionary with some magic strings and bytes that help get coverage faster.
After a couple hours running and getting practically full coverage (verified with
llvm-cov) the fuzzer luckily found no issues.