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  * @requires (os.arch != "sparc") & (os.arch != "sparcv9")
  29  * @run main/othervm compiler.c2.Test8202414
  30  */
  31 
  32 package compiler.c2;
  33 
  34 import sun.misc.Unsafe;
  35 import java.lang.reflect.Field;
  36 import java.security.AccessController;
  37 import java.security.PrivilegedAction;
  38 
  39 public class Test8202414 {
  40 
  41     public static void main(String[] args) {
  42         System.err.close();
  43         int count = 0;
  44         while (count++ < 120000) {
  45           test();
  46         }
  47     }
  48 
  49     public static void test() {
  50         byte[] newBufb = serByte(397);
  51         short[] newBufs = serShort(397);
  52         int[] newBufi = serInt(397);
  53         long[] newBufl = serLong(397);
  54         if (newBufb.length != 397 || newBufs.length != 397
  55             || newBufi.length != 397 || newBufl.length != 397) {
  56             System.out.println("array length internal error");
  57             throw new RuntimeException("Test failed");
  58         }
  59 
  60     }
  61 
  62     public static byte[] serByte(int bufLen) {
  63         byte[] buf = new byte[bufLen];
  64         THE_UNSAFE.putByte(buf, BYTE_ARRAY_BASE_OFFSET + 1, (byte) buf.length);
  65         System.err.println("ref " + buf);
  66         return buf;
  67     }
  68 
  69     public static short[] serShort(int bufLen) {
  70         short[] buf = new short[bufLen];
  71         THE_UNSAFE.putShort(buf, SHORT_ARRAY_BASE_OFFSET + 1, (short) buf.length);
  72         System.err.println("ref " + buf);
  73         return buf;
  74     }
  75 
  76     public static int[] serInt(int bufLen) {
  77         int[] buf = new int[bufLen];
  78         THE_UNSAFE.putInt(buf, INT_ARRAY_BASE_OFFSET + 1, buf.length);
  79         System.err.println("ref " + buf);
  80         return buf;
  81     }
  82 
  83     public static long[] serLong(int bufLen) {
  84         long[] buf = new long[bufLen];
  85         THE_UNSAFE.putLong(buf, LONG_ARRAY_BASE_OFFSET + 1, buf.length);
  86         System.err.println("ref " + buf);
  87         return buf;
  88     }
  89 
  90     /* Unsafe fields and initialization
  91      */
  92     static final Unsafe THE_UNSAFE;
  93     static final long BYTE_ARRAY_BASE_OFFSET;
  94     static final long SHORT_ARRAY_BASE_OFFSET;
  95     static final long INT_ARRAY_BASE_OFFSET;
  96     static final long LONG_ARRAY_BASE_OFFSET;
  97     static {
  98         THE_UNSAFE = (Unsafe) AccessController.doPrivileged (
  99             new PrivilegedAction<Object>() {
 100                 @Override
 101                 public Object run() {
 102                     try {
 103                         Field f = Unsafe.class.getDeclaredField("theUnsafe");
 104                         f.setAccessible(true);
 105                         return f.get(null);
 106                     } catch (NoSuchFieldException | IllegalAccessException e) {
 107                         throw new Error();
 108                     }
 109                 }
 110             }
 111         );
 112         BYTE_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(byte[].class);
 113         SHORT_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(short[].class);
 114         INT_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(int[].class);
 115         LONG_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(long[].class);
 116     }
 117 }