On Mon, 13 May 2024 11:38:40 GMT, Maurizio Cimadamore <mcimadam...@openjdk.org> wrote:
>> This PR implements [JEP 472](https://openjdk.org/jeps/472), by restricting >> the use of JNI in the following ways: >> >> * `System::load` and `System::loadLibrary` are now restricted methods >> * `Runtime::load` and `Runtime::loadLibrary` are now restricted methods >> * binding a JNI `native` method declaration to a native implementation is >> now considered a restricted operation >> >> This PR slightly changes the way in which the JDK deals with restricted >> methods, even for FFM API calls. In Java 22, the single >> `--enable-native-access` was used both to specify a set of modules for which >> native access should be allowed *and* to specify whether illegal native >> access (that is, native access occurring from a module not specified by >> `--enable-native-access`) should be treated as an error or a warning. More >> specifically, an error is only issued if the `--enable-native-access flag` >> is used at least once. >> >> Here, a new flag is introduced, namely >> `illegal-native-access=allow/warn/deny`, which is used to specify what >> should happen when access to a restricted method and/or functionality is >> found outside the set of modules specified with `--enable-native-access`. >> The default policy is `warn`, but users can select `allow` to suppress the >> warnings, or `deny` to cause `IllegalCallerException` to be thrown. This >> aligns the treatment of restricted methods with other mechanisms, such as >> `--illegal-access` and the more recent `--sun-misc-unsafe-memory-access`. >> >> Some changes were required in the package-info javadoc for >> `java.lang.foreign`, to reflect the changes in the command line flags >> described above. > > Maurizio Cimadamore has updated the pull request incrementally with one > additional commit since the last revision: > > Avoid call to VM::isModuleSystemInited > Use initial error stream src/java.base/share/classes/jdk/internal/reflect/Reflection.java line 124: > 122: if (module != null) { > 123: // not in init phase > 124: Holder.JLA.ensureNativeAccess(module, owner, methodName, > currentClass); In an earlier iteration I had a call to `VM::isModuleSystemInited`, but I discovered that caused a performance regression, since that method involves a volatile access. Perhaps we should rethink that part of the init code to use stable fields, but it's probably better done separately. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/19213#discussion_r1598328283
