1335469 - Firefox 53.0a2 sends RTCP receiver reports with incorrect SSRC

Status: RESOLVED DUPLICATE of bug 1337810

(Core :: WebRTC: Networking, defect, P1)

Description

[Eric Bunyan]

Attachment: firefox_dev_wrong_rtcp_ssrc.pcap

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:50.0) Gecko/20100101 Firefox/50.0
Build ID: 20161209094039

Steps to reproduce:

Make a call to or from Firefox dev (53.0a2) including both audio and video (I did not test with only audio or only video, but I imagine the same issue happens).


Actual results:

Receiver reports use a sender SSRC that is not from the SDP (neither offer nor answer).

Oddly the last two receiver reports in the attached pcap did use the correct SSRCs, but none of the many previous ones. I tried calling Firefox dev to Firefox dev using apprtc and got the same problem.


Expected results:

Both sender and receiver reports should use the SSRC declared in the SDP for the sender SSRC.

Comment 1

[Loic]

Is it a recent regression? Did it use to work with FF51?

Comment 2

[Nils Ohlmeier [:drno]]

I just tested 52 vs 54 on this topic and it looks like we have a problem here. Probably fall out from the 49 landing (is my guess).

With 52 I see RTCP Sender and Receiver reports having SSRC's at the topmost level which match one of the RTP streams.

With 54 I see RTCP Sender reports topmost SSRC matching a RTP stream. But the RTCP Receiver reports have an SSRC in them which does not match any of the RTP streams.

Note: this observation is only from looking at PCAPs taken from calls on webrtc-landing

Comment 3

[Nico Grunbaum [:ng, @chew:mozilla.org]]

I tested this using an instrumented a build off of rev c8db5ac137c5, which is post 49 merge. This is a side effect of bug 1325447. The SSRCs in the receiver reports were the temporary SSRCs, then those SSRCs stopped appearing once the real SSRCs were in place.

I think this can be marked as duplicate, and the priority of bug 1325447 should be bumped. drno, agreed?

Comment 4

[Nico Grunbaum [:ng, @chew:mozilla.org]]

Repeating that test with a fresh inbound build, I did not see the randomly generated SSRC stop appearing in receiver reports. I still think it is a side effect of bug 1325447.

Comment 5

[Nils Ohlmeier [:drno]]

Sounds good to me. Let's leave this one open here until we have fixed bug 1325447 and can verify that this problem is indeed fixed.

Comment 6

[Nils Ohlmeier [:drno]]

Eric we just landed a fix in bug 1337810 which I believe should fix this issue as well. The fix should show up in tomorrow Nightly. Would be great if you could check if this fixes your issue as well and report back.

Comment 7

[Eric Bunyan]

Testing with "55.0a1 (2017-03-08) (64-bit)" I still see the same issue.

Comment 8

[Nils Ohlmeier [:drno]]

Thanks for testing Eric. I was optimistic the fix in bug 1337810 would make it into last nights Nightly build, but it did not. As the fix landed in mozilla-central a couple of hours ago it would be great if you could test again with tomorrows Nightly (2017-03-09).

Comment 9

[Eric Bunyan]

All the values I checked look correct in "55.0a1 (2017-03-09) (64-bit)". Thank you.

Comment 10

[Nils Ohlmeier [:drno]]

Thanks for double checking Eric. Appreciated!

Then I'll just close this here, because the patch landed already via bug 1337810.