[WIP] Fix crashes when passing arrays via reflection

[aoli-al]

If a method signature has Object type and it receives an array via reflection, Phosphor cannot identify this and will lead to java.lang.ClassCastException.

Initially I was planning to simply expand this check for all methods

phosphor/Phosphor/src/main/java/edu/columbia/cs/psl/phosphor/instrumenter/TaintPassingMV.java

Line 135 in 177ab28

} else if (ensureObjsAreWrapped && args[i].getInternalName().equals("java/lang/Object")) {

It seems not working because it calls Phosphor inside JDK when JVM is initialized (and cause another crash). It seems that we need to maintain an allow list either:

1. call this wrapper for specific methods
2. do not call this wrapper for specific methods

It seems plan 2 is more robust but building that list exhaustively is hard. Please let me know what you think and I'm happy to bring a patch.

Ps. if you want to see a realistic example, the class is
https://github.com/openjdk/jdk/blob/a39cf2e3b242298fbf5fafdb8aa9b5d4562061ef/src/java.base/share/classes/sun/security/x509/BasicConstraintsExtension.java#L114

[jon-bell]

Yes, I've run into this one before, too :/

phosphor/Phosphor/src/main/java/edu/columbia/cs/psl/phosphor/instrumenter/TaintPassingMV.java

Line 86 in 177ab28

ensureObjsAreWrapped = true; //TODO should we always do this? just in some places? performance is what? If try everywhere, it crashes...

I haven't had a chance yet to run and step through your failing test case, but I think that for the case of reflection, this is not the right direction to be going. We should be intercepting reflective calls and ensuring that primitive arrays are represented by their corresponding wrappers.