Automatically assigning owner based on suspected regression changelist https://chromium.googlesource.com/chromium/src/+/be2d8dcbe045805779a972a32bc1433dd782b01a (Document `CBORReader`'s limitations and their reasons.).

If this is incorrect, please let us know why and apply the Test-Predator-Wrong-CLs label. If you aren't the correct owner for this issue, please unassign yourself as soon as possible so it can be re-triaged.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/62403b01f1a3edbe0676d4b1f44fa5cb33013006

commit 62403b01f1a3edbe0676d4b1f44fa5cb33013006
Author: Chris Palmer <palmer@chromium.org>
Date: Mon Sep 17 22:44:05 2018

Don't `NOTREACHED` when handling malformed CBOR inputs.

Just return `nullopt` and (crucially) set the error code without crashing.

Bug: 879237, 884382 
Change-Id: I899ceb45648e130d5352a0a487c2d244f41a118d
Reviewed-on: https://chromium-review.googlesource.com/1228938
Commit-Queue: Chris Palmer <palmer@chromium.org>
Reviewed-by: Balazs Engedy <engedy@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#591854}
[modify] https://crrev.com/62403b01f1a3edbe0676d4b1f44fa5cb33013006/components/cbor/cbor_reader.cc

ClusterFuzz has detected this issue as fixed in range 591853:591858.

Detailed report: https://clusterfuzz.com/testcase?key=4507740716924928

Fuzzer: libFuzzer_ctap_response_fuzzer
Job Type: libfuzzer_chrome_asan_debug
Platform Id: linux

Crash Type: CHECK failure
Crash Address: 
Crash State:
  false. Unsupported major type in cbor_reader.cc
  cbor::CBORReader::DecodeCompleteDataItem
  cbor::CBORReader::ReadMapContent
  
Sanitizer: address (ASAN)

Regressed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_asan_debug&range=591227:591228
Fixed: https://clusterfuzz.com/revisions?job=libfuzzer_chrome_asan_debug&range=591853:591858

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=4507740716924928

See https://chromium.googlesource.com/chromium/src/+/master/testing/libfuzzer/reference.md for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.

ClusterFuzz testcase 4507740716924928 is verified as fixed, so closing issue as verified.

If this is incorrect, please add ClusterFuzz-Wrong label and re-open the issue.