Josh Bleecher Snyder b3d6704aa3 wgengine/magicsock: fix data race on endpoint.discoKey
endpoint.discoKey is protected by endpoint.mu.
endpoint.sendDiscoMessage was reading it without holding the lock.
This showed up in a CI failure and is readily reproducible locally.

The fix is in two parts.

First, for Conn.enqueueCallMeMaybe, eliminate the one-line helper method endpoint.sendDiscoMessage; call Conn.sendDiscoMessage directly.
This makes it more natural to read endpoint.discoKey in a context
in which endpoint.mu is already held.

Second, for endpoint.sendDiscoPing, explicitly pass the disco key
as an argument. Again, this makes it easier to read endpoint.discoKey
in a context in which endpoint.mu is already held.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
2021-11-17 17:49:33 -08:00
..
2021-11-02 17:50:15 -07:00