kundaji, this one might be related to your CL as well.

reassigning to kundaji@ as he has a fix for all of the fuzzer bugs.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c6d437f401a1b5053d7d1bf3aa2b13c99d854e70

commit c6d437f401a1b5053d7d1bf3aa2b13c99d854e70
Author: kundaji <kundaji@chromium.org>
Date: Fri Dec 02 00:46:45 2016

Set main frame id on DataUseRecorder created for render frame.

Without this id, there is no way to look this instance up in the
render frame map.

BUG=670257, 670240 , 670438 

Review-Url: https://codereview.chromium.org/2545963002
Cr-Commit-Position: refs/heads/master@{#435797}

[modify] https://crrev.com/c6d437f401a1b5053d7d1bf3aa2b13c99d854e70/chrome/browser/data_use_measurement/chrome_data_use_ascriber.cc

ClusterFuzz has detected this issue as fixed in range 435745:435840.

Detailed report: https://cluster-fuzz.appspot.com/testcase?key=5538247192346624

Fuzzer: jsbell_serviceworker
Job Type: linux_msan_chrome
Platform Id: linux

Crash Type: Use-of-uninitialized-value
Crash Address: 
Crash State:
  net::LayeredNetworkDelegate::OnURLRequestDestroyed
  net::NetworkDelegate::NotifyURLRequestDestroyed
  net::NetworkDelegate::NotifyURLRequestDestroyed
  
Recommended Security Severity: Medium

Regressed: https://cluster-fuzz.appspot.com/revisions?job=linux_msan_chrome&range=435514:435553
Fixed: https://cluster-fuzz.appspot.com/revisions?job=linux_msan_chrome&range=435745:435840

Minimized Testcase (0.24 Kb): https://cluster-fuzz.appspot.com/download/AMIfv97wvB9D769K3DOt8QcRRJyWvEUGAkZ3EAEbltfaZb65rLPzLwbIdBghp0R3iEMO9eeuN2LVDu7oZAMUiNX8G5blCpx7sT5hLBivO7F1bFfF1FGTPBgt2mxF7Pq5OkxfbCKLNDAjhYwmuS1yn8xLUEXdwF92PA?testcase_id=5538247192346624

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.

ClusterFuzz testcase is verified as fixed, closing issue.

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

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