806822 - WebRTC possible data race with cprGetMessage vs. cprPegSendMessageStats

Status: RESOLVED FIXED

(Core :: WebRTC: Signaling, defect)

Description

[Christoph Diehl [:posidron]]

Attachment: callstack

media/webrtc/signaling/src/sipcc/cpr/linux/cpr_linux_ipc.c:505
    msgq->currentCount--;

media/webrtc/signaling/src/sipcc/cpr/linux/cpr_linux_ipc.c:729
        msgq->maxCount = msgq->currentCount;

This race was confirmed by race verifier.

Tested with m-c changeset: 111684:e19e170d2f6d

Comment 1

[Christoph Diehl [:posidron]]

This is a definite race but I am not sure how important this one might be.

Comment 2

[Randell Jesup [:jesup] (needinfo me)]

Attachment: avoid race condition in gathering stats

Comment 3

[Randell Jesup [:jesup] (needinfo me)]

True race, but non-problematic - at most the stats are wrong, and we ignore the stats.

Comment 4

[Ethan Hugg [:ehugg]]

Comment on attachment 690189 [details] [diff] [review]
avoid race condition in gathering stats

Review of attachment 690189 [details] [diff] [review]:
-----------------------------------------------------------------

lgtm.  Even though we don't currently take advantage of these stats, I'm hesitant take them out yet.

Comment 5

[Randell Jesup [:jesup] (needinfo me)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/13da8dc7b474

Comment 6

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/13da8dc7b474