wgengine/magicsock: don't deadlock on pre-disco Endpoints w/ lazy wireguard configs
Fixes tailscale/tailscale#637
@@ -2653,16 +2653,17 @@ func (c *Conn) CreateEndpoint(pubKey [32]byte, addrs string) (conn.Endpoint, err
pk := key.Public(pubKey)
c.logf("magicsock: CreateEndpoint: key=%s: %s", pk.ShortString(), derpStr(addrs))
+ if !c.canCreateEPUnlocked.Get() { // sorry
+ c.mu.Lock()
+ defer c.mu.Unlock()
+ }
+
if strings.HasSuffix(addrs, controlclient.EndpointDiscoSuffix) {
discoHex := strings.TrimSuffix(addrs, controlclient.EndpointDiscoSuffix)
discoKey, err := key.NewPublicFromHexMem(mem.S(discoHex))
if err != nil {
return nil, fmt.Errorf("magicsock: invalid discokey endpoint %q for %v: %w", addrs, pk.ShortString(), err)
}
- if !c.canCreateEPUnlocked.Get() { // sorry
- c.mu.Lock()
- defer c.mu.Unlock()
- }
de := &discoEndpoint{
c: c,
publicKey: tailcfg.NodeKey(pk), // peer public key (for WireGuard + DERP)
@@ -2706,9 +2707,6 @@ func (c *Conn) CreateEndpoint(pubKey [32]byte, addrs string) (conn.Endpoint, err
}
}
- c.mu.Lock()
- defer c.mu.Unlock()
-
// If this endpoint is being updated, remember its old set of
// endpoints so we can remove any (from c.addrsByUDP) that are
// not in the new set.
