1164453 - crash in mozilla::MediaCodecDataDecoder::InitDecoder(mozilla::jni::Ref<mozilla::widget::sdk::Surface> const&)

Status: RESOLVED FIXED

(Firefox for Android Graveyard :: Audio/Video, defect)

Description

[Aaron Train [:aaronmt]]

This bug was filed from the Socorro interface and is 
report bp-b7847bd6-ae67-42f5-b98b-3936f2150512.
=============================================================

Comment 1

[James Willcox (:snorp) ([e-mail]) (he/him)]

Looks like mCallback is null, which isn't supposed to happen. Eugen, can you look into how/why this could happen? Maybe adding an assertion that aCallback is non-null would be good too.

Comment 2

[Eugen Sawin [:esawin]]

The callback can be set to null in some cases (e.g. [1]), we should always check before calling functions on it.

[1] https://dxr.mozilla.org/mozilla-central/source/dom/media/fmp4/MP4Reader.cpp#99

Comment 3

[Eugen Sawin [:esawin]]

Attachment: 0001-Bug-1164453-Assert-that-decoder-callback-is-set-befo.patch

There are cases where mCallback can be unset (initialization) and others where it must be set (decoding), we should check/assert accordingly.

Comment 4

[Eugen Sawin [:esawin]]

Bug 1160321 has rendered my link in comment 2 obsolete (see https://hg.mozilla.org/mozilla-central/diff/03dc784d5456/dom/media/fmp4/MP4Reader.cpp).

Comment 5

[Eugen Sawin [:esawin]]

Attachment: 0001-Bug-1164453-Assert-that-decoder-callback-is-set-befo.patch

My assumption that we only initialize the decoder without a callback was wrong. We also do it in places ([1]) which eventually call into the decoder loop.
That means, we can never assume that the callback is set.

Also, sorry for introducing a new macro, but sporadic variadic function support in templates may currently cause us issues on some platforms/compiler versions.

[1] https://dxr.mozilla.org/mozilla-central/source/dom/media/fmp4/MP4Decoder.cpp#276

Comment 6

[Eugen Sawin [:esawin]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=85f0a2fd8cc1

Comment 7

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/3b142e9bc1f5

Comment 8

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/3b142e9bc1f5