1 /*
   2  * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /**
  25  * @test
  26  * @bug 8202414
  27  * @summary Unsafe write after primitive array creation may result in array length change
  28  * @run main/othervm compiler.c2.Test8202414
  29  */
  30 
  31 package compiler.c2;
  32 
  33 import sun.misc.Unsafe;
  34 import java.lang.reflect.Field;
  35 import java.security.AccessController;
  36 import java.security.PrivilegedAction;
  37 
  38 public class Test8202414 {
  39 
  40     public static void main(String[] args) {
  41         System.err.close();
  42         int count = 0;
  43         while (count++ < 120000) {
  44           test();
  45         }
  46     }
  47 
  48     public static void test() {
  49         byte[] newBufb = serByte(397);
  50         short[] newBufs = serShort(397);
  51         int[] newBufi = serInt(397);
  52         long[] newBufl = serLong(397);
  53         if (newBufb.length != 397 || newBufs.length != 397
  54             || newBufi.length != 397 || newBufl.length != 397) {
  55             System.out.println("array length internal error");
  56             throw new RuntimeException("Test failed");
  57         }
  58 
  59     }
  60 
  61     public static byte[] serByte(int bufLen) {
  62         byte[] buf = new byte[bufLen];
  63         THE_UNSAFE.putByte(buf, BYTE_ARRAY_BASE_OFFSET + 1, (byte) buf.length);
  64         System.err.println("ref " + buf);
  65         return buf;
  66     }
  67 
  68     public static short[] serShort(int bufLen) {
  69         short[] buf = new short[bufLen];
  70         THE_UNSAFE.putShort(buf, SHORT_ARRAY_BASE_OFFSET + 1, (short) buf.length);
  71         System.err.println("ref " + buf);
  72         return buf;
  73     }
  74 
  75     public static int[] serInt(int bufLen) {
  76         int[] buf = new int[bufLen];
  77         THE_UNSAFE.putInt(buf, INT_ARRAY_BASE_OFFSET + 1, buf.length);
  78         System.err.println("ref " + buf);
  79         return buf;
  80     }
  81 
  82     public static long[] serLong(int bufLen) {
  83         long[] buf = new long[bufLen];
  84         THE_UNSAFE.putLong(buf, LONG_ARRAY_BASE_OFFSET + 1, buf.length);
  85         System.err.println("ref " + buf);
  86         return buf;
  87     }
  88 
  89     /* Unsafe fields and initialization
  90      */
  91     static final Unsafe THE_UNSAFE;
  92     static final long BYTE_ARRAY_BASE_OFFSET;
  93     static final long SHORT_ARRAY_BASE_OFFSET;
  94     static final long INT_ARRAY_BASE_OFFSET;
  95     static final long LONG_ARRAY_BASE_OFFSET;
  96     static {
  97         THE_UNSAFE = (Unsafe) AccessController.doPrivileged (
  98             new PrivilegedAction<Object>() {
  99                 @Override
 100                 public Object run() {
 101                     try {
 102                         Field f = Unsafe.class.getDeclaredField("theUnsafe");
 103                         f.setAccessible(true);
 104                         return f.get(null);
 105                     } catch (NoSuchFieldException | IllegalAccessException e) {
 106                         throw new Error();
 107                     }
 108                 }
 109             }
 110         );
 111         BYTE_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(byte[].class);
 112         SHORT_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(short[].class);
 113         INT_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(int[].class);
 114         LONG_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(long[].class);
 115     }
 116 }