rpcserver: remove session after registration error

Author: bitromortac

session_rpcserver.go

@@ -1286,6 +1286,17 @@ func (s *sessionRpcServer) AddAutopilotSession(ctx context.Context,
 		privacyFlags.Serialize(),
 	)
 	if err != nil {
+		// If we tried to link to a previous session, we delete the
+		// newly created session in the case of errors to avoid having
+		// non-revoked sessions lying around.
+		if len(req.LinkedGroupId) != 0 {
+			deleteErr := s.cfg.db.DeleteReservedSession(
+				ctx, sess.ID,
+			)
+			log.Errorf("error deleting session after failed "+
+				"linking attempt: %v", deleteErr)
+		}
+
 		return nil, fmt.Errorf("error registering session with "+
 			"autopilot server: %v", err)
 	}