commit ccc9d979a5291e62096ac645c4ce9873afc40496
author Tommi <tommi@webrtc.org> Thu Mar 24 07:12:36 2022
committer WebRTC LUCI CQ <webrtc-scoped@luci-project-accounts.iam.gserviceaccount.com> Thu Mar 24 08:18:43 2022
tree 9a86c2e407d8b50942151853a92009de321e0b0f
parent b6b34fc213fd2b13f527037e4220df14b680e214

Add checks for a null msg_queue_ to VirtualSocketServer.

The Thread class internally (`Thread::DoDestroy`) makes this call:
  ss_->SetMessageQueue(nullptr);

Which sets the `msg_queue_` member variable of VirtualSocketServer
to nullptr. VSS checks for this in several places, but not all. In
particular `CancelConnects()` does handle it, but Disconnect(), which
is called from the same place (VirtualSocket::Close()), is missing
this check.

This CL adds some DCHECKs to catch when a pointer might be nullptr
and also avoids dereferencing a potential nullptr deref during teardown
if `Disconnect` is called, e.g. from within `VirtualSocket::Close()`
which is called from the dtor of `VirtualSocket`.

Bug: webrtc:13864
Change-Id: I717a0f033ebf70b1f59338680957723a77ccf4ca
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/256600
Reviewed-by: Niels Moller <nisse@webrtc.org>
Commit-Queue: Tomas Gunnarsson <tommi@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36312}