libn/networkdb: SetPrimaryKey() under a write lock

corhere · corhere · commit c9b01e0c4c54 · 2025-05-14T19:45:14.000-04:00
(*NetworkDB).SetPrimaryKey() acquires a read lock on the NetworkDB
instance. That seems sound on the surface as it is only reading from the
NetworkDB struct, not mutating it. However, concurrent calls to
(*memberlist.Keyring).UseKey() would get flagged by Go's race detector
due to some questionable locking in its implementation. Acquire an
exclusive lock in SetPrimaryKey so concurrent calls don't race each
other.

Signed-off-by: Cory Snider &lt;csnider@mirantis.com&gt;
diff --git a/libnetwork/networkdb/cluster.go b/libnetwork/networkdb/cluster.go
@@ -71,8 +71,8 @@ func (nDB *NetworkDB) SetKey(key []byte) {
 // been added apriori through SetKey
 func (nDB *NetworkDB) SetPrimaryKey(key []byte) {
 	log.G(context.TODO()).Debugf("Primary Key %.5s", hex.EncodeToString(key))
-	nDB.RLock()
-	defer nDB.RUnlock()
+	nDB.Lock()
+	defer nDB.Unlock()
 	for _, dbKey := range nDB.config.Keys {
 		if bytes.Equal(key, dbKey) {
 			if nDB.keyring != nil {
