Suspected CL through code search on file MessagePort.cpp
https://chromium.googlesource.com/chromium/src/+/84f5959aa09e9841e5aea9993247b46b42a60d9a
yuryu@, could you please take a look and help us to find correct owner if it is not related your changes.

My change is just to move a function to another file, and isn't touching any line. I think it's quite unlikely that the change introduces any regressions. I'm new to the development and have little idea to find out the right owner... What to do?

Thanks yuryu@ for the inputs. i will triage this issue.

Suspected CL but not 100% sure though
https://chromium.googlesource.com/chromium/src/+/f7dbf39be31d8aa9214d5d84da613508d4e06491
tzik@, could you please take a look and reassign if it is not related your changes.

Removing EditIssue view restrictions from ClusterFuzz filed bugs. If you believe that this issue should still be restricted, please reapply the label.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

ClusterFuzz has detected this issue as fixed in range 435159:435209.

Detailed report: https://cluster-fuzz.appspot.com/testcase?key=5861494304800768

Fuzzer: inferno_layout_test_unmodified
Job Type: linux_lsan_chrome_mp
Platform Id: linux

Crash Type: UNKNOWN READ
Crash Address: 0x000000000000
Crash State:
  blink::MessagePort::dispatchMessages
  Invoke<blink::CrossThreadPersistent<blink::MessagePort>>
  MakeItSo<void
  
Regressed: https://cluster-fuzz.appspot.com/revisions?job=linux_lsan_chrome_mp&range=419848:419971
Fixed: https://cluster-fuzz.appspot.com/revisions?job=linux_lsan_chrome_mp&range=435159:435209

Minimized Testcase (1.56 Kb): https://cluster-fuzz.appspot.com/download/AMIfv95FDlsqiawUe2B7MKaDh3m1jfxHAM4wYouuQzsFlA_sifWpmzC8jWdPZpbyk1LzxpcN9w6jUROnvO527abxqM5kiQMAtxG4kFWQSYUwdbkAvujFh-tIG1N7gdW377M9g8Ta1iGP4hDFCJcCJJLyrcjHhVoueQ?testcase_id=5861494304800768

See https://dev.chromium.org/Home/chromium-security/bugs/reproducing-clusterfuzz-bugs for more information.

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