8202414: Unsafe write after primitive array creation may result in array length change
Summary: Avoided collecting unaligned stores in Initialize node by making can_capture_store return false for same
Reviewed-by: dlong, kvn, vlivanov
diff --git a/src/share/vm/opto/memnode.cpp b/src/share/vm/opto/memnode.cpp
index af56937..14b0ff9 100644
--- a/src/share/vm/opto/memnode.cpp
+++ b/src/share/vm/opto/memnode.cpp
@@ -3353,9 +3353,6 @@
// within the initialized memory.
intptr_t InitializeNode::can_capture_store(StoreNode* st, PhaseTransform* phase, bool can_reshape) {
const int FAIL = 0;
- if (st->is_unaligned_access()) {
- return FAIL;
- }
if (st->req() != MemNode::ValueIn + 1)
return FAIL; // an inscrutable StoreNode (card mark?)
Node* ctl = st->in(MemNode::Control);
@@ -3371,6 +3368,10 @@
return FAIL; // inscrutable address
if (alloc != allocation())
return FAIL; // wrong allocation! (store needs to float up)
+ int size_in_bytes = st->memory_size();
+ if ((size_in_bytes != 0) && (offset % size_in_bytes) != 0) {
+ return FAIL; // mismatched access
+ }
Node* val = st->in(MemNode::ValueIn);
int complexity_count = 0;
if (!detect_init_independence(val, complexity_count))
diff --git a/test/compiler/c2/Test8202414.java b/test/compiler/c2/Test8202414.java
new file mode 100644
index 0000000..1d8ef8d
--- /dev/null
+++ b/test/compiler/c2/Test8202414.java
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2019, Huawei Technologies Co. Ltd. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @bug 8202414
+ * @summary Unsafe write after primitive array creation may result in array length change
+ * @requires (os.arch != "sparc") & (os.arch != "sparcv9")
+ * @run main/othervm compiler.c2.Test8202414
+ */
+
+package compiler.c2;
+
+import sun.misc.Unsafe;
+import java.lang.reflect.Field;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+
+public class Test8202414 {
+
+ public static void main(String[] args) {
+ System.err.close();
+ int count = 0;
+ while (count++ < 120000) {
+ test();
+ }
+ }
+
+ public static void test() {
+ byte[] newBufb = serByte(397);
+ short[] newBufs = serShort(397);
+ int[] newBufi = serInt(397);
+ long[] newBufl = serLong(397);
+ if (newBufb.length != 397 || newBufs.length != 397
+ || newBufi.length != 397 || newBufl.length != 397) {
+ System.out.println("array length internal error");
+ throw new RuntimeException("Test failed");
+ }
+
+ }
+
+ public static byte[] serByte(int bufLen) {
+ byte[] buf = new byte[bufLen];
+ THE_UNSAFE.putByte(buf, BYTE_ARRAY_BASE_OFFSET + 1, (byte) buf.length);
+ System.err.println("ref " + buf);
+ return buf;
+ }
+
+ public static short[] serShort(int bufLen) {
+ short[] buf = new short[bufLen];
+ THE_UNSAFE.putShort(buf, SHORT_ARRAY_BASE_OFFSET + 1, (short) buf.length);
+ System.err.println("ref " + buf);
+ return buf;
+ }
+
+ public static int[] serInt(int bufLen) {
+ int[] buf = new int[bufLen];
+ THE_UNSAFE.putInt(buf, INT_ARRAY_BASE_OFFSET + 1, buf.length);
+ System.err.println("ref " + buf);
+ return buf;
+ }
+
+ public static long[] serLong(int bufLen) {
+ long[] buf = new long[bufLen];
+ THE_UNSAFE.putLong(buf, LONG_ARRAY_BASE_OFFSET + 1, buf.length);
+ System.err.println("ref " + buf);
+ return buf;
+ }
+
+ /* Unsafe fields and initialization
+ */
+ static final Unsafe THE_UNSAFE;
+ static final long BYTE_ARRAY_BASE_OFFSET;
+ static final long SHORT_ARRAY_BASE_OFFSET;
+ static final long INT_ARRAY_BASE_OFFSET;
+ static final long LONG_ARRAY_BASE_OFFSET;
+ static {
+ THE_UNSAFE = (Unsafe) AccessController.doPrivileged (
+ new PrivilegedAction<Object>() {
+ @Override
+ public Object run() {
+ try {
+ Field f = Unsafe.class.getDeclaredField("theUnsafe");
+ f.setAccessible(true);
+ return f.get(null);
+ } catch (NoSuchFieldException | IllegalAccessException e) {
+ throw new Error();
+ }
+ }
+ }
+ );
+ BYTE_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(byte[].class);
+ SHORT_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(short[].class);
+ INT_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(int[].class);
+ LONG_ARRAY_BASE_OFFSET = THE_UNSAFE.arrayBaseOffset(long[].class);
+ }
+}
