This issue is a security regression. If you are not able to fix this quickly, please revert the change that introduced it.

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

rockot - looks like you have some experience here, could you take a look?  Thanks!

Thanks. Lumping this together with a crash based ultimately on the same fundamental threading issue I introduced to MessagePort recently. Fix in progress.

ClusterFuzz has detected this issue as fixed in range 458277:458282.

Detailed report: https://clusterfuzz.com/testcase?key=5563423690850304

Fuzzer: therealholden_worker
Job Type: linux_msan_chrome
Platform Id: linux

Crash Type: Use-of-uninitialized-value
Crash Address: 
Crash State:
  content::MessagePort::State::ArmWatcher
  mojo::edk::Watch::InvokeCallback
  mojo::edk::RequestContext::~RequestContext
  
Sanitizer: memory (MSAN)

Recommended Security Severity: Medium

Regressed: https://clusterfuzz.com/revisions?job=linux_msan_chrome&range=456626:457732
Fixed: https://clusterfuzz.com/revisions?job=linux_msan_chrome&range=458277:458282

Reproducer Testcase: https://clusterfuzz.com/download/AMIfv96NNOmhtv7ro6Q1o2OWj-9zT5FBZJvHi9ya9zGtao3ojwx2fRtGa2lM0KR5lACgrvhMtzbIjrOHaJzVmIDgHTjSDmk8ZxhxJRjInMLrvFS7w8KXmK_mir3MJT_eX155s5QdjQdla7XrdQMRNHWv2xsWJybDrKJuCCJo6oDjo2XfPQxmbtesJIQ-mrIIE19U1sOzH4Jf0ZwO30jA5Z5FGLj2tJzWjMgNfsUI7zv9BbPiPlVb8vHnmScxG2SRMnRqrk-ev8UnUT6V0t5ZU_zoJ7Af_E8DzOSBDP1UaG_fVNX2nJ5iZqeIJBEavoW8SkkhkASGmA3Qts6gcYH68Y6-oDDi4pjCE5NU4WXgXLePfOAoAprepBewkzSkYd4LlDxOzvdHgMBsh2YDkTK8pHvz4Xu5IuBYmA?testcase_id=5563423690850304


Additional requirements: Requires HTTP

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.

This bug has been closed for more than 14 weeks. Removing security view restrictions.

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