1418331 - Crash in mozilla::camera::VideoEngine::CreateVideoCapture

Status: RESOLVED FIXED

(Core :: WebRTC: Audio/Video, defect, P2)

Description

[Calixte Denizet (:calixte)]

This bug was filed from the Socorro interface and is
report bp-8149661c-dd64-4b8d-aa4c-b07280171117.
=============================================================

Top 10 frames of crashing thread:

0 xul.dll mozilla::camera::VideoEngine::CreateVideoCapture dom/media/systemservices/VideoEngine.cpp:51
1 xul.dll <lambda_08cbd13f79f629363b36fc2f39d9a0c6>::operator dom/media/systemservices/CamerasParent.cpp:724
2 xul.dll MessageLoop::DoWork ipc/chromium/src/base/message_loop.cc:535
3 xul.dll mozilla::ipc::MessagePumpForNonMainUIThreads::DoRunLoop ipc/glue/MessagePump.cpp:403
4 xul.dll base::MessagePumpWin::Run ipc/chromium/src/base/message_pump_win.h:80
5 xul.dll MessageLoop::RunHandler ipc/chromium/src/base/message_loop.cc:319
6 xul.dll MessageLoop::Run ipc/chromium/src/base/message_loop.cc:299
7 xul.dll base::Thread::ThreadMain ipc/chromium/src/base/thread.cc:181
8 xul.dll `anonymous namespace'::ThreadFunc ipc/chromium/src/base/platform_thread_win.cc:28
9 kernel32.dll BaseThreadInitThunk 

=============================================================

There is 1 crash in nightly 59.0a1 with buildid 20171116220410. In analyzing the backtrace, the regression may have been introduced by patch [1] to fix bug 1399413.

[1] https://hg.mozilla.org/mozilla-central/rev/08ae44b6836c

Comment 1

[Alex Chronopoulos [:achronop]]

Just got it on a win 10 Dell XPS 13
https://crash-stats.mozilla.com/report/index/b75a946f-c295-4752-8fcf-7caf00171119

Also when I go to gum test -> Video I get: Failed allocate videosource

Comment 2

[Alex Chronopoulos [:achronop]]

navigator.mediaDevices.enumerateDevices().then( v => v.forEach(d => console.log(d.kind + " " + d.deviceId)))
Promise { <state>: "pending" }
videoinput IWrHEk8CFMmqO8/ZwY/pOc8Fas1soq3W6silAAVHtj4= debugger eval code:1:69
audioinput 8ZjghNrcyTW4ZQamfI46V2O+HkxtWqenuz/i++/ZQKQ= debugger eval code:1:69
audioinput M7kkQ7hqzWP2X+OJvKmx4Za1ywrZ7tclT+Mhaxgirk0= debugger eval code:1:69
audioinput oe+55gzOZZlMUXXqZV0ykBtgqlGvIX2bzatOAWd8Aus=

Comment 3

[Munro Mengjue Chiang [:mchiang] Be Mozillian since 1/19/2018]

Attachment: Bug 1418331 - add null protection.

Review commit: https://reviewboard.mozilla.org/r/202676/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/202676/

Comment 4

[Munro Mengjue Chiang [:mchiang] Be Mozillian since 1/19/2018]

We need more information to figure out the crash root cause.

Comment 5

[Paul Adenot (:padenot)]

Munro, can you get a minidump from crash-stats, validate the fact that there is a nullptr here, and null-check, so, at least, we don't crash?

Ping me on irc if you don't know how to get a minidump, or to debug using it.

Comment 6

[Nils Ohlmeier [:drno]]

Comment on attachment 8931548 [details]
Bug 1418331 - add null protection.

https://reviewboard.mozilla.org/r/202676/#review208592

LGTM

Comment 7

[Munro Mengjue Chiang [:mchiang] Be Mozillian since 1/19/2018]

I will analyze the minidump first.

Comment 8

[Munro Mengjue Chiang [:mchiang] Be Mozillian since 1/19/2018]

The minidump shows that it.second.VideoCapture() == null.
It's possibly because webrtc::VideoCaptureFactory::Create() or webrtc::DesktopCaptureImpl::Create() return nullptr.
I will add some null protection and MOZ_ASSERT to diagnose further.

Comment 9

[Munro Mengjue Chiang [:mchiang] Be Mozillian since 1/19/2018]

Comment on attachment 8931548 [details]
Bug 1418331 - add null protection.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/202676/diff/1-2/

Comment 10

[Munro Mengjue Chiang [:mchiang] Be Mozillian since 1/19/2018]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=f54fae9df1ec64fe0ea0c0bb86cf88aadf46c6eb&selectedJob=148088722

Comment 11

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4ca7e0cfe84e
add null protection. r=drno

Comment 12

[Tiberius Oros[:tiberius_oros]]

https://hg.mozilla.org/mozilla-central/rev/4ca7e0cfe84e

Comment 13

[Tiberius Oros[:tiberius_oros]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/4ca7e0cfe84e