Dale, since this can be related to Audio, could you please help to triage?

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

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Looks like it's crashing here https://cs.chromium.org/chromium/src/media/audio/audio_output_device.cc?l=428

=> grunell, guidou, olka

AOD is accessed on IO thread after deleted on main thread. Could happen if Stop() is never called on it. When moving to Mojo we'll get rid of living on two threads, that will solve it properly. Meanwhile, seems like the solution is to make sure Stop() is always called.

Assigning to Olga to look at the new mixing code.

CL under review https://codereview.chromium.org/2275343002/

ClusterFuzz has detected this issue as fixed in range 415049:415582.

Detailed report: https://cluster-fuzz.appspot.com/testcase?key=5854749121576960

Fuzzer: ochang_search_index_mutator
Job Type: linux_asan_chrome_chromeos
Platform Id: linux

Crash Type: Heap-use-after-free READ 1
Crash Address: 0x6070000876d1
Crash State:
  base::WaitableEvent::Signal
  content::AudioMessageFilter::OnChannelClosing
  IPC::ChannelProxy::Context::OnRemoveFilter
  
Recommended Security Severity: Medium

Regressed: https://cluster-fuzz.appspot.com/revisions?job=linux_asan_chrome_chromeos&range=413455:413506
Fixed: https://cluster-fuzz.appspot.com/revisions?job=linux_asan_chrome_chromeos&range=415049:415582

Unminimized Testcase: https://cluster-fuzz.appspot.com/download/AMIfv95XqSfkvfVPPOxuIu0FpSwsHswkhuBtj5D5NVELaQCzIzvW-wF-lyGq_SlU8SI5mYOkTEKQ2otopq8a0wXI3Sc5vNLkY-XQnNoovKJWHkFBTpeUleuwj2r9Qsk5fMNVeg6_MM77MPdG5-NXtFspvktKEVlj2w?testcase_id=5854749121576960


Additional requirements: Requires Gestures

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.

Your change meets the bar and is auto-approved for M54 (branch: 2840)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4048f667b58d4a55da76ebea5d3aae61d30c8f53

commit 4048f667b58d4a55da76ebea5d3aae61d30c8f53
Author: olka <olka@chromium.org>
Date: Thu Sep 08 11:01:15 2016

Stopping cached AudioOutputDevices on AudioRendererSinkCache destruction.

BUG= 640576 

Review-Url: https://codereview.chromium.org/2275343002
Cr-Commit-Position: refs/heads/master@{#415296}
(cherry picked from commit 7c54ad8cf953810135f3684e4eada4c5625efe1c)

TBR=dalecurtis@chromium.org
NOTRY=true
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2323463003
Cr-Commit-Position: refs/branch-heads/2840@{#232}
Cr-Branched-From: 1ae106dbab4bddd85132d5b75c670794311f4c57-refs/heads/master@{#414607}

[modify] https://crrev.com/4048f667b58d4a55da76ebea5d3aae61d30c8f53/content/renderer/media/audio_renderer_sink_cache_impl.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4048f667b58d4a55da76ebea5d3aae61d30c8f53

commit 4048f667b58d4a55da76ebea5d3aae61d30c8f53
Author: olka <olka@chromium.org>
Date: Thu Sep 08 11:01:15 2016

Stopping cached AudioOutputDevices on AudioRendererSinkCache destruction.

BUG= 640576 

Review-Url: https://codereview.chromium.org/2275343002
Cr-Commit-Position: refs/heads/master@{#415296}
(cherry picked from commit 7c54ad8cf953810135f3684e4eada4c5625efe1c)

TBR=dalecurtis@chromium.org
NOTRY=true
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2323463003
Cr-Commit-Position: refs/branch-heads/2840@{#232}
Cr-Branched-From: 1ae106dbab4bddd85132d5b75c670794311f4c57-refs/heads/master@{#414607}

[modify] https://crrev.com/4048f667b58d4a55da76ebea5d3aae61d30c8f53/content/renderer/media/audio_renderer_sink_cache_impl.cc

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