Address review feedback

builtin/credential/approle/backend.go

@@ -61,13 +61,13 @@ func Backend(conf *logical.BackendConfig) (*backend, error) {
 		salt: salt,
 
 		// Create the map of locks to modify the registered roles
-		roleLocksMap: map[string]*sync.RWMutex{},
+		roleLocksMap: make(map[string]*sync.RWMutex, 257),
 
 		// Create the map of locks to modify the generated RoleIDs.
-		roleIDLocksMap: map[string]*sync.RWMutex{},
+		roleIDLocksMap: make(map[string]*sync.RWMutex, 257),
 
 		// Create the map of locks to modify the generated SecretIDs.
-		secretIDLocksMap: map[string]*sync.RWMutex{},
+		secretIDLocksMap: make(map[string]*sync.RWMutex, 257),
 	}
 
 	// Create 256 locks each for managing RoleID and SecretIDs. This will avoid

helper/locksutil/locks.go

@@ -16,6 +16,10 @@ func CreateLocks(p map[string]*sync.RWMutex, count int64) error {
 		return fmt.Errorf("invalid count: %d", count)
 	}
 
+	if p == nil {
+		return fmt.Errorf("map of locks is not initialized")
+	}
+
 	for i := int64(0); i < count; i++ {
 		p[fmt.Sprintf("%02x", i)] = &sync.RWMutex{}
 	}