net/netcheck: don't keep a home DERP region that was removed from the map

Browse Source

When control removes our home DERP region, magicsock drops the
connection, clears its home, and does a ReSTUN (since #3664). But
the netcheck stickiness checks could still pick the removed region
again, because they keyed off the previous report's PreferredDERP and
recent DERP frame activity, both of which outlive the removal.

Ignore the previous preferred region, and ForcePreferredDERP, when
they're no longer in the current DERP map.

Updates #21673

Change-Id: Ib3b7f62b6861a73d0893d6b3011dfac20bc93117
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

...

This commit is contained in:

500 Internal Server Error

Gitea Version: 1.28.0+dev-477-g8b6ad49a5f