8260403: javap should be more robust in the face of invalid class files

Reviewed-by: vromero

src/jdk.jdeps/share/classes/com/sun/tools/javap/ClassWriter.java

@@ -229,6 +229,8 @@ public class ClassWriter extends BasicWriter {
                 }
             } catch (ConstantPoolException e) {
                 print(report(e));
+            } catch (IllegalStateException e) {
+                report("Invalid value for Signature attribute: " + e.getMessage());
             }
         }
 
@@ -500,7 +502,7 @@ public class ClassWriter extends BasicWriter {
                 methodExceptions = methodType.throwsTypes;
                 if (methodExceptions != null && methodExceptions.isEmpty())
                     methodExceptions = null;
-            } catch (ConstantPoolException e) {
+            } catch (ConstantPoolException | IllegalStateException e) {
                 // report error?
                 // fall back on standard descriptor
                 methodType = null;

test/langtools/tools/javap/8260403/InvalidSignature.jcod

@@ -0,0 +1,120 @@
+class InvalidSignature {
+  0xCAFEBABE;
+  0; // minor version
+  52; // version
+  [] { // Constant Pool
+    ; // first element is empty
+    Method #4 #14; // #1
+    String #15; // #2
+    class #16; // #3
+    class #17; // #4
+    Utf8 "<init>"; // #5
+    Utf8 "()V"; // #6
+    Utf8 "Code"; // #7
+    Utf8 "LineNumberTable"; // #8
+    Utf8 "m"; // #9
+    Utf8 "m2"; // #10
+    Utf8 "()Ljava/lang/String;"; // #11
+    Utf8 "SourceFile"; // #12
+    Utf8 "InvalidSignature.java"; // #13
+    NameAndType #5 #6; // #14
+    Utf8 "Hello"; // #15
+    Utf8 "InvalidSignature"; // #16
+    Utf8 "java/lang/Object"; // #17
+    Utf8 "Signature"; // #18
+    Utf8 "', '"; // #19
+  } // Constant Pool
+
+  0x0020; // access
+  #3;// this_cpx
+  #4;// super_cpx
+
+  [] { // Interfaces
+  } // Interfaces
+
+  [] { // fields
+  } // fields
+
+  [] { // methods
+    { // Member
+      0x0000; // access
+      #5; // name_cpx
+      #6; // sig_cpx
+      [] { // Attributes
+        Attr(#7) { // Code
+          1; // max_stack
+          1; // max_locals
+          Bytes[]{
+            0x2AB70001B1;
+          };
+          [] { // Traps
+          } // end Traps
+          [] { // Attributes
+            Attr(#8) { // LineNumberTable
+              [] { // LineNumberTable
+                0  1;
+              }
+            } // end LineNumberTable
+          } // Attributes
+        } // end Code
+      } // Attributes
+    } // Member
+    ;
+    { // Member
+      0x0000; // access
+      #9; // name_cpx
+      #6; // sig_cpx
+      [] { // Attributes
+        Attr(#7) { // Code
+          0; // max_stack
+          1; // max_locals
+          Bytes[]{
+            0xB1;
+          };
+          [] { // Traps
+          } // end Traps
+          [] { // Attributes
+            Attr(#8) { // LineNumberTable
+              [] { // LineNumberTable
+                0  2;
+              }
+            } // end LineNumberTable
+          } // Attributes
+        } // end Code
+      } // Attributes
+    } // Member
+    ;
+    { // Member
+      0x0000; // access
+      #9; // name_cpx
+      #11; // sig_cpx
+      [] { // Attributes
+        Attr(#7) { // Code
+          1; // max_stack
+          1; // max_locals
+          Bytes[]{
+            0x1202B0;
+          };
+          [] { // Traps
+          } // end Traps
+          [] { // Attributes
+            Attr(#8) { // LineNumberTable
+              [] { // LineNumberTable
+                0  3;
+              }
+            } // end LineNumberTable
+          } // Attributes
+        } // end Code
+      } // Attributes
+    } // Member
+  } // methods
+
+  [] { // Attributes
+    Attr(#12) { // SourceFile
+      #13;
+    }; // end SourceFile
+    Attr(#18) { // Signature
+      #19;
+    } // end Signature
+  } // Attributes
+} // end class InvalidSignature

test/langtools/tools/javap/8260403/T8260403.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2021, 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 8260403
+ * @summary javap should be more robust in the face of invalid class files
+ * @build InvalidSignature
+ * @run main T8260403
+ * @modules jdk.jdeps/com.sun.tools.javap
+ */
+import java.io.PrintWriter;
+
+public class T8260403 {
+
+    public static void main(String args[]) throws Exception {
+        if (com.sun.tools.javap.Main.run(new String[]{"-c", System.getProperty("test.classes") + "/InvalidSignature.class"},
+                new PrintWriter(System.out)) != 0) {
+            throw new AssertionError();
+        }
+    }
+}