Automatically applying components based on crash stacktrace and information from OWNERS files.

If this is incorrect, please apply the Test-Predator-Wrong-Components label.

Automatically assigning owner based on suspected regression changelist https://chromium.googlesource.com/chromium/src/+/347092291b208b8e4e1d70ca0079931817c94736 (Worker: Make sure to post messages after dedicated worker script evaluation).

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/+/eed2d5f4f6f40e3f6e5c12aa90d06f3f73208065

commit eed2d5f4f6f40e3f6e5c12aa90d06f3f73208065
Author: Hiroki Nakagawa <nhiroki@chromium.org>
Date: Tue Mar 20 08:15:44 2018

Worker: Avoid nullptr access in DedicatedWorkerMessagingProxy

This CL avoids posting tasks via GetWorkerThread() after worker termination is
requested. In that case, GetWorkerThread() may return nullptr.

This bug was added by:
https://chromium-review.googlesource.com/c/chromium/src/+/967914

Bug:  823550 
Change-Id: I81ef06548d386d23521c4b68d6b4af73c495ef89
Reviewed-on: https://chromium-review.googlesource.com/970041
Commit-Queue: Hiroki Nakagawa <nhiroki@chromium.org>
Reviewed-by: Makoto Shimazu <shimazu@chromium.org>
Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#544307}
[modify] https://crrev.com/eed2d5f4f6f40e3f6e5c12aa90d06f3f73208065/third_party/WebKit/Source/core/workers/DedicatedWorkerMessagingProxy.cpp

Issue 823717 has been merged into this issue.

I'm now running a clusterfuzz task to verify the fix.

ClusterFuzz has detected this issue as fixed in range 544306:544308.

Detailed report: https://clusterfuzz.com/testcase?key=6410522971602944

Fuzzer: inferno_twister
Job Type: linux_ubsan_vptr_chrome
Platform Id: linux

Crash Type: Null-dereference READ
Crash Address: 0x000000000000
Crash State:
  blink::DedicatedWorkerMessagingProxy::DidEvaluateScript
  void base::internal::Invoker<base::internal::BindState<void
  blink::RunCrossThreadClosure
  
Sanitizer: undefined (UBSAN)

Regressed: https://clusterfuzz.com/revisions?job=linux_ubsan_vptr_chrome&range=543995:543997
Fixed: https://clusterfuzz.com/revisions?job=linux_ubsan_vptr_chrome&range=544306:544308

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=6410522971602944

Additional requirements: Requires HTTP

See https://github.com/google/clusterfuzz-tools 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 6410522971602944 is verified as fixed, so closing issue as verified.

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