ICU-23334 Fix plurrule_fuzzer: clamp UPluralType enum and add NULL check#3933
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OwenSanzas wants to merge 1 commit intounicode-org:mainfrom
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ICU-23334 Fix plurrule_fuzzer: clamp UPluralType enum and add NULL check#3933OwenSanzas wants to merge 1 commit intounicode-org:mainfrom
OwenSanzas wants to merge 1 commit intounicode-org:mainfrom
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1. Clamp UPluralType to valid values (0=CARDINAL, 1=ORDINAL) before passing to PluralRules::forLocale(). Raw fuzz bytes can produce arbitrary enum values which is undefined behavior. 2. Add nullptr check in TestPluralRules before calling pp->select() to guard against edge cases where forLocale returns NULL with U_ZERO_ERROR status. 3. Replace deprecated UPLURAL_TYPE_COUNT with explicit value 2. Coverage: +15.81% edge coverage (+368 edges) in 60s run.
OwenSanzas
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Summary
UPluralType typeis read directly from fuzz data viamemcpy, allowing arbitrary integer values. Only 0 (CARDINAL) and 1 (ORDINAL) are valid — passing other values toPluralRules::forLocale()is undefined behavior. Fix: clamp with% 2after reading.nullptrguard inTestPluralRulesbefore callingpp->select(), matching the defensive pattern in other ICU fuzzers.UPLURAL_TYPE_COUNT(deprecated) with explicit2.Coverage
60-second LibFuzzer run, empty seed corpus, ASan instrumentation:
Both original and fixed fuzzers run clean (no crashes).