Summary

Throw an IllegalArgumentException in Symbol.libraryLookup(Path path, Arena arena) if the path is not in the default file system.

Problem

The Symbol.libraryLookup(Path path, Arena arena) method ignores any custom file system as it always uses the default file system anyhow (as it ultimately relies on dlopen).

Solution

As it is very difficult (if not impossible) to support custom file systems for library loading, it is better to throw an exception rather than just silently stripping away the file system used. This is also more secure as there is no ambiguity as to the path of the library that should be loaded by the method.

Specification

diff --git a/src/java.base/share/classes/java/lang/foreign/SymbolLookup.java b/src/java.base/share/classes/java/lang/foreign/SymbolLookup.java
index 1d04032a1ff3..de955a025419 100644
--- a/src/java.base/share/classes/java/lang/foreign/SymbolLookup.java
+++ b/src/java.base/share/classes/java/lang/foreign/SymbolLookup.java

@@ -284,6 +285,7 @@ static SymbolLookup libraryLookup(String name, Arena arena) {
      * @throws WrongThreadException if {@code arena} is a confined arena, and this method
      *         is called from a thread {@code T}, other than the arena's owner thread
      * @throws IllegalArgumentException if {@code path} does not point to a valid library
+     *         in the default file system
      * @throws IllegalCallerException If the caller is in a module that does not have
      *         native access enabled
      */