harfbuzz/hb-shape-fuzzer: Heap-buffer-overflow in BEInt<unsigned char, 1>::operator unsigned char

Project:
https://github.com/harfbuzz/harfbuzz.git

Detailed report: https://oss-fuzz.com/testcase?key=5735679418433536

Project: harfbuzz
Fuzzer: libFuzzer_harfbuzz_hb-shape-fuzzer
Fuzz target binary: hb-shape-fuzzer
Job Type: libfuzzer_asan_harfbuzz
Platform Id: linux

Crash Type: Heap-buffer-overflow READ 1
Crash Address: 0x60700000033e
Crash State:
BEInt<unsigned char, 1>::operator unsigned char
OT::KernSubTableFormat3::get_kerning
hb_kern_machine_t<OT::KernSubTableFormat3>::kern

Sanitizer: address (ASAN)

Recommended Security Severity: Medium

Regressed: https://oss-fuzz.com/revisions?job=libfuzzer_asan_harfbuzz&range=201811020143:201811030141

Reproducer Testcase: https://oss-fuzz.com/download?testcase_id=5735679418433536

Issue filed automatically.

See https://github.com/google/oss-fuzz/blob/master/docs/reproducing.md for more information.

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