undefect. CWE-407 — 63 sites patched across 27 ecosystems

Authors: russell@unturf.com · brackishbert@gmail.com · foxhop.net · TimeHexOn.com

Patches, unit tests, benchmarks, whitepaper, and outreach briefs.
Public domain — no copyright claimed. Use freely.

test/jdk/java/nio/Buffer/LimitDirectMemory.java

@@ -0,0 +1,145 @@
+/*
+ * Copyright (c) 2002, 2025, Oracle and/or its affiliates. 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 4627316 6743526
+ * @summary Test option to limit direct memory allocation
+ * @library /test/lib
+ *
+ * @summary Test: memory is properly limited using multiple buffers
+ * @run main/othervm -XX:MaxDirectMemorySize=10 LimitDirectMemory true 10 1
+ * @run main/othervm -XX:MaxDirectMemorySize=1k LimitDirectMemory true 1k 100
+ * @run main/othervm -XX:MaxDirectMemorySize=10m LimitDirectMemory true 10m 10m
+ *
+ * @summary Test: We can increase the amount of available memory
+ * @run main/othervm -XX:MaxDirectMemorySize=65M LimitDirectMemory false 64M 65M
+ *
+ * @summary Test: Exactly the default amount of memory is available
+ * @run main/othervm LimitDirectMemory false 10 1
+ * @run main/othervm -Xmx64m LimitDirectMemory false 0 DEFAULT
+ * @run main/othervm -Xmx64m LimitDirectMemory true 0 DEFAULT+1
+ *
+ * @summary Test: We should be able to eliminate direct memory allocation entirely
+ * @run main/othervm -XX:MaxDirectMemorySize=0 LimitDirectMemory true 0 1
+ *
+ * @summary Test: Setting the system property should not work so we should be able
+ *                to allocate the default amount
+ * @run main/othervm -Dsun.nio.MaxDirectMemorySize=1K -Xmx64m
+ *                   LimitDirectMemory false DEFAULT-1 DEFAULT/2
+ */
+
+import java.nio.ByteBuffer;
+import java.util.Properties;
+
+public class LimitDirectMemory {
+    private static final int K = 1024;
+
+    public static void main(String [] args) throws Exception {
+        if (args.length < 2) {
+            throw new IllegalArgumentException("Usage: "
+                    + "java LimitDirectMemory"
+                    + " <OOME_expected(true|false)>"
+                    + " <fill_direct_memory>"
+                    + " <size_per_buffer>");
+        }
+        boolean throwp = parseThrow(args[0]);
+        int size = parseSize(args[1]);
+        int incr = (args.length > 2 ? parseSize(args[2]) : size);
+
+        Properties p = System.getProperties();
+        if (p.getProperty("sun.nio.MaxDirectMemorySize") != null)
+            throw new RuntimeException("sun.nio.MaxDirectMemorySize defined");
+
+        ByteBuffer [] b = new ByteBuffer[K];
+
+        // Fill up most/all of the direct memory
+        int i = 0;
+        while (size >= incr) {
+            b[i++] = ByteBuffer.allocateDirect(incr);
+            size -= incr;
+        }
+
+        if (throwp) {
+            try {
+                b[i] = ByteBuffer.allocateDirect(incr);
+                throw new RuntimeException("OutOfMemoryError not thrown: "
+                                           + incr);
+            } catch (OutOfMemoryError e) {
+                e.printStackTrace(System.out);
+                System.out.println("OK - Error thrown as expected ");
+            }
+        } else {
+            b[i] = ByteBuffer.allocateDirect(incr);
+            System.out.println("OK - Error not thrown");
+        }
+    }
+
+    private static boolean parseThrow(String s) {
+        if (s.equals("true"))  return true;
+        if (s.equals("false")) return false;
+        throw new RuntimeException("Unrecognized expectation: " + s);
+    }
+
+    private static int parseSize(String size) throws Exception {
+
+        if (size.equals("DEFAULT"))
+            return (int)Runtime.getRuntime().maxMemory();
+        if (size.equals("DEFAULT+1"))
+            return (int)Runtime.getRuntime().maxMemory() + 1;
+        if (size.equals("DEFAULT+1M"))
+            return (int)Runtime.getRuntime().maxMemory() + (1 << 20);
+        if (size.equals("DEFAULT-1"))
+            return (int)Runtime.getRuntime().maxMemory() - 1;
+        if (size.equals("DEFAULT/2"))
+            return (int)Runtime.getRuntime().maxMemory() / 2;
+
+        int idx = 0, len = size.length();
+
+
+        for (int i = 0; i < len; i++) {
+            if (Character.isDigit(size.charAt(i))) idx++;
+            else break;
+        }
+
+        if (idx == 0)
+            throw new RuntimeException("No digits detected: " + size);
+
+        int result = Integer.parseInt(size.substring(0, idx));
+
+        if (idx < len) {
+            for (int i = idx; i < len; i++) {
+                switch(size.charAt(i)) {
+                case 'T': case 't': result *= K; // fall through
+                case 'G': case 'g': result *= K; // fall through
+                case 'M': case 'm': result *= K; // fall through
+                case 'K': case 'k': result *= K;
+                    break;
+                default:
+                    throw new RuntimeException("Unrecognized size: " + size);
+                }
+            }
+        }
+        return result;
+    }
+}