Summary:
First step toward addressing bad traces that happen in examples like
```
void sourceMethod() {
Obj source = (Obj) InferTaint.inferSecretSource();
callSameSink(null, source); // index: 1
}
void callSameSink(Obj o1, Obj o2) {
callMySink1(o1); // flows via o1 ~= index 0, don't expand
callMySink2(o2); // flows via o2 ~= index 1, can expand
}
void callMySink1(Obj o) {
... // maybe interesting something happens here that doesn't happen in callMySink2
InferTaint.inferSensitiveSink(o); // flows via o ~= index 0, can expand
}
void callMySink2(Obj o) {
InferTaint.inferSensitiveSink(o); // flows via o ~= index 0, can expand
}
```
The issue is that when we recreate a trace to the sink starting from `sourceMethod`, we don't know which of the calls to `callMySink` to expand/include in the trace.
If we expand the call to `callMySink(o1)`, we'll get a bogus trace.
In this example that's not such a big deal, but imagine the case where the first call to `callMySink` is a different function that transitively calls the sink through some long and confusing path.
Remembering the index at which taint flows into each sink will let us choose which sinks are safe to expand.
This diff just adds indexes to the API; it's not actually propagating the index info or using it during expansion yet.
Reviewed By: jeremydubreil
Differential Revision: D5170563
fbshipit-source-id: ba4b096
master
Sam Blackshear8 years agocommitted byFacebook Github Bot
Sam Blackshear
8 years ago
committed by
Facebook Github Bot