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/langtools/tools/javac/linenumbers/NestedLineNumberTest.java

@@ -0,0 +1,52 @@
+/*
+ * @test /nodynamiccopyright/
+ * @bug 8061778
+ * @summary  Wrong LineNumberTable for default constructors
+ */
+
+import java.util.List;
+import java.lang.classfile.*;
+import java.lang.classfile.attribute.*;
+
+import java.io.IOException;
+
+public class NestedLineNumberTest {
+
+    public static void main(String[] args) throws Exception {
+        List<LineNumberInfo> lines = findEntries();
+        if (lines == null || lines.size() != 1) {
+            int found = lines == null ? 0 : lines.size();
+            error(String.format("LineNumberTable contains wrong number of entries - expected %d, found %d", 1, found));
+        }
+
+        int line = lines.get(0).lineNumber();
+        if (line != 49) {
+            error(String.format("LineNumberTable contains wrong line number - expected %d, found %d", 49, line));
+        }
+    }
+
+    static List<LineNumberInfo> findEntries() throws IOException {
+        ClassModel self = ClassFile.of().parse(NestedLineNumberTest.Test.class.getResourceAsStream("NestedLineNumberTest$Test.class").readAllBytes());
+        for (MethodModel m : self.methods()) {
+            if ("<init>".equals(m.methodName().stringValue())) {
+                CodeAttribute code_attribute = m.findAttribute(Attributes.code()).orElseThrow();
+                for (Attribute<?> at : code_attribute.attributes()) {
+                    if (at instanceof LineNumberTableAttribute lineAt) {
+                        return lineAt.lineNumbers();
+                    }
+                }
+            }
+        }
+        return null;
+    }
+
+    static void error(String msg) {
+        throw new AssertionError(msg);
+    }
+
+    // The default constructor in this class should get only one LineNumberTable entry,
+    // pointing to the first line of the declaration of class Test.
+    static class Test {
+        static class Empty { }
+    }
+}