RFR: 8013527: calling MethodHandles.lookup on itself leads to errors [v2]

[Mandy Chung]

On Wed, 3 Feb 2021 19:42:16 GMT, Johannes Kuhn <github.com+652983+DasBrain at openjdk.org> wrote:

>> `MethodHandle -> Method.invoke -> MethodHandles.lookup() ` is a corner case that can be fixed easily using the class data approach.  See the new commit.
>
> The security issue I mentioned was in an other branch, method-invoke.  
> 
> I used commit https://github.com/mlchung/jdk/commit/4a3c914f1b46cf84b42f6b6bc19d421955faac3f (i.e. before strengthening the injected invoker checks) to test the [my exploit](https://gist.github.com/DasBrain/4dda6cc3a13e1636afe17e6a02ec3d12). (Yes, full sandbox escape.)
> 
> I hope the same is not possible with the nestmate requirement.  
> 
> PS.: Hidden Class -> MethodHandle -> Method.invoke -> MethodHandles might break due to mangling of the hidden class name for the injected invoker. Will write a test.

Well, my branch `method-invoke` is a prototype and work-in-progress.   I won't dig too much to it.

Do you reproduce the issue with this patch?   The fix will ensure it's the invoker class injected by BindCaller.

-------------

PR: https://git.openjdk.java.net/jdk/pull/2367