pdftract/notes/bf-5jzdf.md

Verification of profile_yaml Fuzz Harness Structure

Bead ID: bf-5jzdf
Date: 2026-07-06
Task: Verify profile_yaml fuzz harness file structure

Summary

Verified that fuzz/fuzz_targets/profile_yaml.rs exists and follows the proper fuzzer structure with all required components.

Acceptance Criteria Verification

Criterion	Status	Details
File exists	✅ PASS	fuzz/fuzz_targets/profile_yaml.rs is present (774 bytes)
#![no_main] attribute	✅ PASS	Line 11 contains #![no_main]
Uses libfuzzer_sys::fuzz_target!	✅ PASS	Line 12 imports libfuzzer_sys::fuzz_target
Proper UTF-8 handling	✅ PASS	Lines 16-19: std::str::from_utf8(data) with early return on Err
Calls load_profile_yaml	✅ PASS	Line 22: pdftract_core::profiles::loader::load_profile_yaml(yaml_content)
No syntax errors	✅ PASS	File compiles cleanly, follows same pattern as other fuzz targets

Comparison with Other Fuzz Targets

Verified against cmap_parser.rs to confirm structural consistency:

• Both use #![no_main]
• Both import libfuzzer_sys::fuzz_target
• Both use fuzz_target!(|data: &[u8]| { ... }); macro
• Both have proper documentation comments

Code Review

The fuzz target correctly implements INV-8 (no panic at public boundary) for the profile YAML loader:

• Converts input bytes to UTF-8 string with early return on invalid UTF-8
• Calls load_profile_yaml and discards the result (testing only that it doesn't panic)
• Has clear documentation explaining what invariant it tests

Conclusion

Result: All acceptance criteria PASS. The profile_yaml fuzz harness file structure is correct and ready for use.

Status: ✅ COMPLETE - No changes needed, file structure is correct.