commit b8841f8ebe03fd9dec42cd95be2c032fe80abc87
author Andy Tamilo <andytamilo@gmail.com> Fri Jul 26 07:49:03 2024
committer WebRTC LUCI CQ <webrtc-scoped@luci-project-accounts.iam.gserviceaccount.com> Wed Aug 14 09:29:55 2024
tree b5bd2d928e605811e3d12b76d12240c84e7bf366
parent 4fffeabba33be186bfb700577bc500629a9af519

Fix race condition on ObjCNetworkMonitor::network_monitor_

There is a race condition on reading
`ObjCNetworkMonitor::_network_monitor` field.
The `ObjCNetworkMonitor::OnPathUpdate()` checks its nullability
on the org.webrtc.RTCDispatcherNetworkMonitor thread BEFORE the
`ObjCNetworkMonitor::Start()` assigns it on the network_monitor thread.
In addition, this field is neither atomic nor protected by mutex so its
last assigned value is not guaranteed to be visible to
another [reading] thread.

Bug: webrtc:355238623
Change-Id: I1a05215111cc873b7d4931824e18f281aebfb91f
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/357880
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Taylor Brandstetter <deadbeef@webrtc.org>
Reviewed-by: Peter Hanspers <peterhanspers@webrtc.org>
Reviewed-by: Jonas Oreland <jonaso@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#42778}