fuzzing: add cjson_print_roundtrip_fuzzer for print/serialize paths#1029
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XananasX7 wants to merge 1 commit into
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fuzzing: add cjson_print_roundtrip_fuzzer for print/serialize paths#1029XananasX7 wants to merge 1 commit into
XananasX7 wants to merge 1 commit into
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Add a new libFuzzer harness that exercises cJSON's print/serialization code paths, which are not covered by the existing cjson_read_fuzzer: - cJSON_ParseWithLength(): parse with explicit length (catches off-by-one) - cJSON_PrintUnformatted(): serialize parsed trees to compact JSON - cJSON_Print(): formatted serialization - cJSON_PrintBuffered(): buffered print with small prebuf forces realloc - cJSON_Duplicate(): deep copy of parsed trees - Round-trip consistency: parse -> print -> re-parse These paths manipulate heap-allocated string buffers and are reachable whenever a caller serializes a parsed or programmatically built cJSON tree.
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Summary
Adds a new libFuzzer harness for cJSON's serialization (print) code paths, which are currently unexercised by OSS-Fuzz.
New harness:
fuzzing/cjson_print_roundtrip_fuzzer.cCoverage added:
cJSON_ParseWithLength()— parse with explicit length (catches boundary bugs)cJSON_PrintUnformatted()— compact serialization of parsed treescJSON_Print()— formatted serializationcJSON_PrintBuffered()with 16-byte prebuf — forces internal buffer reallocationcJSON_Duplicate()— deep copy exercises recursive tree traversalWhy this matters
The existing
cjson_read_fuzzeronly callscJSON_Parse(). The print/serialize code paths allocate and grow heap buffers dynamically and are reachable whenever a caller serializes a cJSON tree. A parse-triggered deep/wide tree fed intocJSON_Print()could trigger integer overflows in buffer size calculations.Build
Integrates with the existing
fuzzing/ossfuzz.sh— one new$CCline added.