Crash on OTAudioDevice protocol with the func estimatedRenderDelay()

[YoavGro]

Hi, we are experiencing some crashes with OTAudioDevice.

The call stack is the following:

Crashed: WebRTCWorkerThread

• 0 Riverside 0xe4ff4 @objc RVSAudioDeviceManager.estimatedRenderDelay() + 4377530356
• 1 Riverside 0x38b20c otc_audio_proxy_playout_delay + 4380307980
• 2 Riverside 0x3f98ec callback_playout_delay(otk_audio_device*) + 4380760300
• 3 Riverside 0x3f92ac webrtc::OTAudioDevice::PlayoutDelay(unsigned short&) const + 4380758700
• 4 Riverside 0x39637c webrtc::OTAudioDeviceModule::PlayoutDelay(unsigned short*) const + 4380353404
• 5 Riverside 0x420ea4 webrtc::voe::(anonymous namespace)::ChannelReceive::UpdatePlayoutTimestamp(bool, long long) + 4380921508
• 6 Riverside 0x41fd08 webrtc::voe::(anonymous namespace)::ChannelReceive::OnRtpPacket(webrtc::RtpPacketReceived const&) + 4380917000
• 7 Riverside 0x697ab4 webrtc::RtpDemuxer::OnRtpPacket(webrtc::RtpPacketReceived const&) + 4383505076
• 8 Riverside 0x699488 webrtc::RtpStreamReceiverController::OnRtpPacket(webrtc::RtpPacketReceived const&) + 4383511688
• 9 Riverside 0x4279dc webrtc::internal::Call::DeliverRtp(webrtc::MediaType, rtc::CopyOnWriteBuffer, long long) + 4380948956
• 10 Riverside 0x427d9c webrtc::internal::Call::DeliverPacket(webrtc::MediaType, rtc::CopyOnWriteBuffer, long long) + 4380949916
• 11 Riverside 0x65cd34 cricket::WebRtcVoiceMediaChannel::OnPacketReceived(rtc::CopyOnWriteBuffer, long long) + 4383264052
• 12 Riverside 0x4dacc4 rtc::FireAndForgetAsyncClosure<cricket::BaseChannel::OnRtpPacket(webrtc::RtpPacketReceived const&)::$_6>::Execute() + 4381682884
• 13 Riverside 0x4faeec rtc::AsyncInvoker::OnMessage(rtc::Message*) + 4381814508
• 14 Riverside 0x512fa0 rtc::Thread::Dispatch(rtc::Message*) + 4381912992
• 15 Riverside 0x512014 rtc::Thread::ProcessMessages(int) + 4381909012
• 16 Riverside 0x5133a4 rtc::Thread::PreRun(void*) + 4381914020
• 17 libsystem_pthread.dylib 0x19ac _pthread_start + 148
• 18 libsystem_pthread.dylib 0xe68 thread_start + 8

We are using pod 'OpenTok', '~> 2.22.3'

[ronenmv]

following Yoav's question, the crash is happening cause of UInt32 to UInt16 casting,
a possible solution is :

public func estimatedRenderDelay() -> UInt16 {
let value = min(self.playoutDelay, UInt32(UInt16.max))
return UInt16(value)
}

this would avoid the crash I guess, but it might cause unexpected result,
please advice

[v-kpheng]

Thanks, @YoavGro, for letting us know about this issue. We've been investigating this, actually: https://jira.vonage.com/browse/OPENTOK-48681.

We haven't had any success with reproducing the issue, though. That said, we added some resiliency to one of our sample applications. Can you please see if https://github.com/opentok/opentok-ios-sdk-samples-swift/pull/177/files helps you?

Thanks! 🙏

[v-kpheng]

@goncalocostamendes, does https://github.com/opentok/opentok-ios-sdk-samples-swift/pull/177/files need to be ported to this repo as well?

Please advise. Thanks!

[goncalocostamendes]

The final version is opentok/opentok-ios-sdk-samples-swift#178! We should debated if we port it to this sample as well, yes!

Regarding this issue raised in particular, in objc casting UInt32 to UInt16 should not raise a crash, but an overflow of the variable.

@YoavGro are you using our objc or swift samples (https://github.com/opentok/opentok-ios-sdk-samples or https://github.com/opentok/opentok-ios-sdk-samples-swift)?

[v-kpheng]

@goncalocostamendes, yeah, let's port that to this as well, please. Thanks!

[v-kpheng]

Tracked internally as https://jira.vonage.com/browse/OPENTOK-51225