Ban sun.misc.Unsafe

testsuite/helloworld/tests/java_unsafe/HelloWorld.java

@@ -0,0 +1,46 @@
+import java.io.*;
+import java.util.*;
+import java.lang.reflect.*;
+import sun.misc.Unsafe;
+
+class OffHeapArray {
+    private final static int BYTE = 1;
+    private long size;
+    private long address;
+
+    public OffHeapArray(long size) throws NoSuchFieldException, IllegalAccessException {
+        this.size = size;
+        address = getUnsafe().allocateMemory(size * BYTE);
+    }
+
+    private Unsafe getUnsafe() throws IllegalAccessException, NoSuchFieldException {
+        Field f = Unsafe.class.getDeclaredField("theUnsafe");
+        f.setAccessible(true);
+        return (Unsafe) f.get(null);
+    }
+
+    public void set(long i, byte value) throws NoSuchFieldException, IllegalAccessException {
+        getUnsafe().putByte(address + i * BYTE, value);
+    }
+
+    public int get(long idx) throws NoSuchFieldException, IllegalAccessException {
+        return getUnsafe().getByte(address + idx * BYTE);
+    }
+
+    public long size() {
+        return size;
+    }
+
+    public void freeMemory() throws NoSuchFieldException, IllegalAccessException {
+        getUnsafe().freeMemory(address);
+    }
+}
+
+public class HelloWorld {
+    public static void main(String[] args) throws Exception {
+        OffHeapArray bigarray = new OffHeapArray(64*8*1024*1024);
+        for (int i = 0; i < 131072; i++) bigarray.set(i * 4096 + 16, (byte) 1);
+        System.out.println("Hello, World!");
+    }
+}
+// Source: https://dmoj.ca/src/5961758

testsuite/helloworld/tests/java_unsafe/test.yml

@@ -0,0 +1,6 @@
+language: JAVA8
+time: 5
+memory: 65535
+source: HelloWorld.java
+expect: IR
+feedback: ca.dmoj.java.UnsafeDisallowedException