1504060 - Assertion failure: trackEndTime >= tstamp, at src/dom/media/webm/WebMDemuxer.cpp:621

Status: RESOLVED FIXED

(Core :: Audio/Video: Playback, defect, P3)

Description

[Tyson Smith [:tsmith]]

Attachment: testcase.webm

Reduced with m-c:
BuildID=20181101133336
SourceStamp=182a1b088330a2d72310ae2561004d955571e236

Assertion failure: trackEndTime >= tstamp, at src/dom/media/webm/WebMDemuxer.cpp:621

#0 auto mozilla::WebMDemuxer::GetNextPacket(mozilla::TrackInfo::TrackType, mozilla::MediaRawDataQueue*)::$_2::operator()<void (mozilla::WebMDemuxer::*)(mozilla::NesteggPacketHolder*), mozilla::Maybe<long>&, long>(void (mozilla::WebMDemuxer::*&&)(mozilla::NesteggPacketHolder*), mozilla::Maybe<long>&, long&&) const src/dom/media/webm/WebMDemuxer.cpp:617:9
#1 mozilla::WebMDemuxer::GetNextPacket(mozilla::TrackInfo::TrackType, mozilla::MediaRawDataQueue*) src/dom/media/webm/WebMDemuxer.cpp:632:5
#2 mozilla::WebMTrackDemuxer::NextSample(RefPtr<mozilla::MediaRawData>&) src/dom/media/webm/WebMDemuxer.cpp:1160:10
#3 mozilla::WebMTrackDemuxer::GetSamples(int) src/dom/media/webm/WebMDemuxer.cpp:1179:10
#4 mozilla::MediaFormatReader::DemuxerProxy::Wrapper::GetSamples(int)::'lambda'()::operator()() const src/dom/media/MediaFormatReader.cpp:881:54
#5 mozilla::detail::ProxyFunctionRunnable<mozilla::MediaFormatReader::DemuxerProxy::Wrapper::GetSamples(int)::'lambda'(), mozilla::MozPromise<RefPtr<mozilla::MediaTrackDemuxer::SamplesHolder>, mozilla::MediaResult, true> >::Run() src/obj-firefox/dist/include/mozilla/MozPromise.h:1517:29
#6 mozilla::TaskQueue::Runner::Run() src/xpcom/threads/TaskQueue.cpp:235:12
#7 nsThreadPool::Run() src/xpcom/threads/nsThreadPool.cpp:242:14
#8 non-virtual thunk to nsThreadPool::Run() src/xpcom/threads/nsThreadPool.cpp
#9 nsThread::ProcessNextEvent(bool, bool*) src/xpcom/threads/nsThread.cpp:1245:14
#10 NS_ProcessNextEvent(nsIThread*, bool) src/xpcom/threads/nsThreadUtils.cpp:530:10
#11 mozilla::ipc::MessagePumpForNonMainThreads::Run(base::MessagePump::Delegate*) src/ipc/glue/MessagePump.cpp:334:20
#12 MessageLoop::RunInternal() src/ipc/chromium/src/base/message_loop.cc:325:10
#13 MessageLoop::Run() src/ipc/chromium/src/base/message_loop.cc:298:3
#14 nsThread::ThreadFunc(void*) src/xpcom/threads/nsThread.cpp:505:11
#15 _pt_root src/nsprpub/pr/src/pthreads/ptthread.c:201:5
#16 start_thread (/lib/x86_64-linux-gnu/libpthread.so.0+0x76b9)
#17 clone /build/glibc-Cl5G7W/glibc-2.23/misc/../sysdeps/unix/sysv/linux/x86_64/clone.S:109

Comment 1

[Intermittent Failures Robot]

1 failures in 2978 pushes (0.0 failures/push) were associated with this bug in the last 7 days.

Repository breakdown:
* mozilla-inbound: 1

Platform breakdown:
* linux64: 1

For more details, see:
https://treeherder.mozilla.org/intermittent-failures.html#/bugdetails?bug=1504060&startday=2018-10-29&endday=2018-11-04&tree=all

Comment 2

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Just run into this while looking at bug 1530835. Even created my own test case before realizing we already have a bug and one here.

These WebM's have samples with timestamps greater than the duration specified in the segment header. This shouldn't happen in the sense that muxers shouldn't make such files. However, if muxers are going to misbehave and make such files, there's nothing in our code that prevents this condition firing (as we see in this bug).

I think we should relax the assertion here to instead be a log. We could also take the larger of the segment duration or sample timestamp.

Comment 3

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

Attachment: Bug 1504060 - Log instead of asserting that webm samples do not have timestamps > segment druation. r?alwu

We're able to hit this assertion in the wild due to bad muxers. As such, replace
the assert with a log. If a sample has a time stamp > the segment duration, use
that instead of the duration for calculating our next time stamp. Use an
explicit int64_t type in the signature for our next time stamp calculation
as the logging explicitly expects an int64_t (makes it harder to change the
types involved and footgunning by having a wrong formatter in the logs).

Comment 4

[Bryce Seager van Dyk [:bryce] (he/him) - Not reading bugmail]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=08439c006ec1a733035f59b35dbadfdd483ae5fd

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/2d1930ba617f
Log instead of asserting that webm samples do not have timestamps > segment druation. r=alwu

Comment 6

[Razvan Maries]

https://hg.mozilla.org/mozilla-central/rev/2d1930ba617f

Comment 7

[Intermittent Failures Robot]

1 failures in 2981 pushes (0.0 failures/push) were associated with this bug in the last 7 days.

Repository breakdown:

• autoland: 1

Platform breakdown:

• linux64-qr: 1

For more details, see:
https://treeherder.mozilla.org/intermittent-failures.html#/bugdetails?bug=1504060&startday=2019-02-25&endday=2019-03-03&tree=all