1560611 - Crash in [@ java.lang.NullPointerException: at org.mozilla.gecko.media.CodecProxy.resetBuffers(CodecProxy.java)]

Status: RESOLVED FIXED

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

Description

[Marcia Knous [:marcia]]

This bug is for crash report bp-20cabe8e-2099-45eb-9a64-35fbd0190621.

Seen while looking at nightly: https://bit.ly/2XuohnF. Crash is new in 68 and started in 20190509033505.

Comments: trying to connect to talky.io

Possible regression ranged based on build id: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=65a693623cee0837b4ad0d23241c84cd3ea23e3a&tochange=34a824c75b7b5618a06ba8987c418d6363da5038

Java stack trace:

java.lang.NullPointerException
	at org.mozilla.gecko.media.CodecProxy.resetBuffers(CodecProxy.java:310)
	at org.mozilla.gecko.media.CodecProxy.flush(CodecProxy.java:296)

Comment 1

[Marcia Knous [:marcia]]

Discussed during triage - we need a priority and to figure out a possible regression range here. Thanks.

Comment 2

[Nils Ohlmeier [:drno]]

John, could you please have a look at what is going on here?

Comment 3

[John Lin [:jhlin][:jolin]]

The crashing code is from bug 1540036/D26188.

The elements in mInputBuffers were added in [1] and used immediately at the next line. If any of them were null, the exception should be raised there. Will review the code again to see what could go wrong.

[1] https://searchfox.org/mozilla-central/source/mobile/android/geckoview/src/main/java/org/mozilla/gecko/media/CodecProxy.java#263

Comment 4

[Julien Cristau [:jcristau]]

Should we consider backing out 1540036 from esr68?

Comment 5

[John Lin [:jhlin][:jolin]]

Found what went wrong: the NPE from fillInputBuffer() is caught in input() and translated to error callback[1], so [2] should be guarded with nullness check. I will upload the fix and request uplift after landing in central and beta asap.

[1] https://searchfox.org/mozilla-central/source/mobile/android/geckoview/src/main/java/org/mozilla/gecko/media/CodecProxy.java#246
[2] https://searchfox.org/mozilla-central/source/mobile/android/geckoview/src/main/java/org/mozilla/gecko/media/CodecProxy.java#266

Comment 6

[John Lin [:jhlin][:jolin]]

Attachment: Bug 1560611 - remember valid buffers only. r?jya

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/0c4414e7ab91
remember valid buffers only. r=jya

Comment 8

[Oana Pop-Rus]

https://hg.mozilla.org/mozilla-central/rev/0c4414e7ab91

Comment 9

[Ryan VanderMeulen [:RyanVM]]

Please nominate this for Beta and ESR68 approval when you get a chance.

Comment 10

[John Lin [:jhlin][:jolin]]

Comment on attachment 9078271 [details]
Bug 1560611 - remember valid buffers only. r?jya

Beta/Release Uplift Approval Request

• User impact if declined: Intermittent crashes when seeking video.
• Is this code covered by automated tests?: No
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: No
• If yes, steps to reproduce:
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): The change is trivial and simple.
• String changes made/needed:

ESR Uplift Approval Request

• If this is not a sec:{high,crit} bug, please state case for ESR consideration: Radom crashes are annoying.
• User impact if declined: Intermittent crashes
• Fix Landed on Version: 70
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): The change is trivial and simple.
• String or UUID changes made by this patch:

Comment 11

[John Lin [:jhlin][:jolin]]

(In reply to Ryan VanderMeulen [:RyanVM] from comment #9)

Please nominate this for Beta and ESR68 approval when you get a chance.

Done. Thanks a lot for the reminder!

Comment 12

[Ryan VanderMeulen [:RyanVM]]

Comment on attachment 9078271 [details]
Bug 1560611 - remember valid buffers only. r?jya

Fixes a Fennec crash. Approved for 68.1b3.

Comment 13

[Razvan Maries]

https://hg.mozilla.org/releases/mozilla-beta/rev/6760861cd25c

Comment 14

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/releases/mozilla-esr68/rev/7eeb3be3b8c1