On Tue, 14 May 2024 18:10:28 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 two > additional commits since the last revision: > > - Address review comments > Improve warning for JNI methods, similar to what's described in JEP 472 > Beef up tests > - Address review comments src/java.base/share/classes/java/lang/Module.java line 334: > 332: System.err.printf(""" > 333: WARNING: A native method in %s has been bound > 334: WARNING: %s has been called by %s in %s Note that this line is still not entirely correct, as for code like: // in module a: package a; import b.Foo; public class Foo { public static void main(String... args) { System.load("JNI library implementing Java_b_Bar_nativeMethod"); Bar.nativeMethod(); } } // in module b: package b; public class Bar { public static native void nativeMethod(); } It’ll show `Bar` as the caller of `Bar::nativeMethod()`, even though the caller is `Foo` in this case, which is why I initially suggested just omitting the caller from **JNI** linkage warnings. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/19213#discussion_r1601140578
