This predicate does not override another predicate

[Sim4n6]

Please, I am unable to use an isAdditionalTaintStep() predicate in a Taint Tracking configuration for Javascript, because I am getting this message error This predicate does not override another predicate.

I am using the following prototype 👍🏾

class Configuration extends TaintTracking::Configuration {
...
  override predicate isAdditionalTaintStep(
    DataFlow::Node nodeFrom, DataFlow::Node nodeTo, DataFlow::FlowLabel stateFrom,
    DataFlow::FlowLabel stateTo
  ) {
...
}
}

What am I doing wrong please?

[Sim4n6]

I still have not figure it out , but isAdditionalTaintStep() with enabled flow label is missing from TainTracking configuration ?

[atorralba]

Hey @Sim4n6! In JavaScript, you can consider the predicate isAdditionalTaintStep an override of the basic isAdditionalFlowStep from DataFlow::Configuration, just with flow labels being fixed as taint. Which means that isAdditionalTaintStep exclusively handles taint steps.

If you want to add steps using other flow labels, you can override isAdditionalFlowStep(DataFlow::Node src, DataFlow::Node trg, DataFlow::FlowLabel inlbl, DataFlow::FlowLabel outlbl) instead.