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/io/FileInputStream/NegativeAvailable.java

@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2013, 2024, 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 8010837 8011136
+ * @summary Test if available returns correct value when skipping beyond
+ *          the end of a file.
+ * @author Dan Xu
+ */
+
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.nio.charset.Charset;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+public class NegativeAvailable {
+
+    public static void main(String[] args) throws IOException {
+        final int SIZE = 10;
+        final int SKIP = 5;
+        final int NEGATIVE_SKIP = -5;
+
+        // Create a temporary file with size of 10 bytes.
+        Path tmp = Files.createTempFile(null, null);
+        try {
+            try (BufferedWriter writer =
+                         Files.newBufferedWriter(tmp, Charset.defaultCharset())) {
+                for (int i = 0; i < SIZE; i++) {
+                    writer.write('1');
+                }
+            }
+
+            File tempFile = tmp.toFile();
+            try (FileInputStream fis = new FileInputStream(tempFile)) {
+                if (tempFile.length() != SIZE) {
+                    throw new RuntimeException("unexpected file size = "
+                            + tempFile.length());
+                }
+                long space = skipBytes(fis, SKIP, SIZE);
+                space = skipBytes(fis, NEGATIVE_SKIP, space);
+                space = skipBytes(fis, SKIP, space);
+                space = skipBytes(fis, SKIP, space);
+                space = skipBytes(fis, SKIP, space);
+                space = skipBytes(fis, NEGATIVE_SKIP, space);
+                space = skipBytes(fis, NEGATIVE_SKIP, space);
+            }
+        } finally {
+            Files.deleteIfExists(tmp);
+        }
+    }
+
+    /**
+     *  Skip toSkip number of bytes and return the remaining bytes of the file.
+     */
+    private static long skipBytes(FileInputStream fis, int toSkip, long space)
+            throws IOException {
+        long skip = fis.skip(toSkip);
+        if (skip != toSkip) {
+            throw new RuntimeException("skip() returns " + skip
+                                       + " but expected " + toSkip);
+        }
+        long newSpace = space - toSkip;
+        long remaining = newSpace > 0 ? newSpace : 0;
+        int avail = fis.available();
+        if (avail != remaining) {
+            throw new RuntimeException("available() returns " + avail
+                                       + " but expected " + remaining);
+        }
+
+        System.out.println("Skipped " + skip + " bytes "
+                           + " available() returns " + avail);
+        return newSpace;
+    }
+}