candidate_base.go segmentation violation

[wuchihsu]

Your environment.

• Version: 0.5.7
• OS: Ubuntu

What did you do?

I run WebRTC NewPeerConnection with Trickle ICE. It can connect successfully most of the time but rarely it panic. Is it possible to add recover in func (a *Agent) taskLoop().

What happened?

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x48 pc=0x815301]

goroutine 2350 [running]:
github.com/pion/ice.(*candidateBase).writeTo(0xc00008e600, 0xc000082c00, 0x64, 0x80, 0xa90a20, 0xc00008e540, 0x0, 0x0, 0x0)
        /home/cch/go/src/github.com/pion/ice/candidate_base.go:162 +0x51
github.com/pion/ice.(*Agent).sendSTUN(0xc000099440, 0xc00015c870, 0xa90a20, 0xc00008e600, 0xa90a20, 0xc00008e540)
        /home/cch/go/src/github.com/pion/ice/candidatepair.go:90 +0x75
github.com/pion/ice.(*Agent).sendBindingRequest(0xc000099440, 0xc00015c870, 0xa90a20, 0xc00008e600, 0xa90a20, 0xc00008e540)
        /home/cch/go/src/github.com/pion/ice/agent.go:855 +0x2eb
github.com/pion/ice.(*controlledSelector).PingCandidate(0xc000136300, 0xa90a20, 0xc00008e600, 0xa90a20, 0xc00008e540)
        /home/cch/go/src/github.com/pion/ice/selection.go:225 +0x3e1
github.com/pion/ice.(*Agent).pingAllCandidates(0xc000099440)
        /home/cch/go/src/github.com/pion/ice/agent.go:512 +0x176
github.com/pion/ice.(*controlledSelector).ContactCandidates(0xc000136300)
        /home/cch/go/src/github.com/pion/ice/selection.go:207 +0xc4
github.com/pion/ice.(*Agent).taskLoop(0xc000099440)
        /home/cch/go/src/github.com/pion/ice/agent.go:587 +0x197
created by github.com/pion/ice.NewAgent
        /home/cch/go/src/github.com/pion/ice/agent.go:395 +0x8aa

[hugoArregui]

Hi @wuchihsu, do you mind trying with latest webrtc version (ideally from master)?

[Sean-Der]

Hey @wuchihsu

I believe this is the issue, and should be fixed in the latest! 358dc33

The issue is that we added candidates before we started them (so they had nil sockets when trying to write to them)

[wuchihsu]

OK, thanks! @hugoArregui @Sean-Der I will try latest version.