8219810: javac throws NullPointerException

Reviewed-by: vromero

src/jdk.compiler/share/classes/com/sun/tools/javac/jvm/ClassReader.java

@@ -2199,18 +2199,23 @@ public class ClassReader {
     /** Read a field.
      */
     VarSymbol readField() {
-        long flags = adjustFieldFlags(nextChar());
+        char rawFlags = nextChar();
+        long flags = adjustFieldFlags(rawFlags);
         Name name = poolReader.getName(nextChar());
         Type type = poolReader.getType(nextChar());
         VarSymbol v = new VarSymbol(flags, name, type, currentOwner);
         readMemberAttrs(v);
+        if (Integer.bitCount(rawFlags & (PUBLIC | PRIVATE | PROTECTED)) > 1 ||
+            Integer.bitCount(rawFlags & (FINAL | VOLATILE)) > 1)
+            throw badClassFile("illegal.flag.combo", Flags.toString((long)rawFlags), "field", v);
         return v;
     }
 
     /** Read a method.
      */
     MethodSymbol readMethod() {
-        long flags = adjustMethodFlags(nextChar());
+        char rawFlags = nextChar();
+        long flags = adjustMethodFlags(rawFlags);
         Name name = poolReader.getName(nextChar());
         Type type = poolReader.getType(nextChar());
         if (currentOwner.isInterface() &&
@@ -2259,6 +2264,8 @@ public class ClassReader {
         validateMethodType(name, m.type);
         setParameters(m, type);
 
+        if (Integer.bitCount(rawFlags & (PUBLIC | PRIVATE | PROTECTED)) > 1)
+            throw badClassFile("illegal.flag.combo", Flags.toString((long)rawFlags), "method", m);
         if ((flags & VARARGS) != 0) {
             final Type last = type.getParameterTypes().last();
             if (last == null || !last.hasTag(ARRAY)) {

src/jdk.compiler/share/classes/com/sun/tools/javac/resources/compiler.properties

@@ -2505,6 +2505,9 @@ compiler.misc.malformed.vararg.method=\
 compiler.misc.wrong.version=\
     class file has wrong version {0}.{1}, should be {2}.{3}
 
+compiler.misc.illegal.flag.combo=\
+    class file contains illegal flag combination {0} for {1} {2}
+
 #####
 
 # 0: type, 1: type or symbol

test/langtools/tools/javac/classreader/8219810/BadFieldFlags.jcod

@@ -0,0 +1,76 @@
+//
+//  class BadFieldFlags {
+//      protected int my_field;
+//  }
+//
+class BadFieldFlags {
+  0xCAFEBABE;
+  0; // minor version
+  63; // version
+  [] { // Constant Pool
+    ; // first element is empty
+    Method #2 #3; // #1
+    class #4; // #2
+    NameAndType #5 #6; // #3
+    Utf8 "java/lang/Object"; // #4
+    Utf8 "<init>"; // #5
+    Utf8 "()V"; // #6
+    class #8; // #7
+    Utf8 "BadFieldFlags"; // #8
+    Utf8 "my_field"; // #9
+    Utf8 "I"; // #10
+    Utf8 "Code"; // #11
+    Utf8 "LineNumberTable"; // #12
+    Utf8 "SourceFile"; // #13
+    Utf8 "BadFieldFlags.java"; // #14
+  } // Constant Pool
+
+  0x0020; // access
+  #7;// this_cpx
+  #2;// super_cpx
+
+  [] { // Interfaces
+  } // Interfaces
+
+  [] { // Fields
+    {  // field
+      0x0006; // access *** SHOULD BE 0x0004 ***
+      #9; // name_index
+      #10; // descriptor_index
+      [] { // Attributes
+      } // Attributes
+    }
+  } // Fields
+
+  [] { // Methods
+    {  // method
+      0x0000; // access
+      #5; // name_index
+      #6; // descriptor_index
+      [] { // Attributes
+        Attr(#11) { // Code
+          1; // max_stack
+          1; // max_locals
+          Bytes[]{
+            0x2AB70001B1;
+          }
+          [] { // Traps
+          } // end Traps
+          [] { // Attributes
+            Attr(#12) { // LineNumberTable
+              [] { // line_number_table
+                0  1;
+              }
+            } // end LineNumberTable
+          } // Attributes
+        } // end Code
+      } // Attributes
+    }
+  } // Methods
+
+  [] { // Attributes
+    Attr(#13) { // SourceFile
+      #14;
+    } // end SourceFile
+  } // Attributes
+} // end class BadFieldFlags

test/langtools/tools/javac/classreader/8219810/BadFieldFlagsTest.java

@@ -0,0 +1,12 @@
+/*
+ * @test /nodynamiccopyright/
+ * @bug 8219810
+ * @summary Verify ClassReader detects invalid field access flags combinations
+ * @build BadFieldFlags
+ * @compile/fail/ref=BadFieldFlagsTest.out -XDrawDiagnostics BadFieldFlagsTest.java
+ */
+public class BadFieldFlagsTest {
+    {
+        System.out.println(new BadFieldFlags().my_field);
+    }
+}

test/langtools/tools/javac/classreader/8219810/BadFieldFlagsTest.out

@@ -0,0 +1,2 @@
+BadFieldFlagsTest.java:10:32: compiler.err.cant.access: BadFieldFlags, (compiler.misc.bad.class.file.header: BadFieldFlags.class, (compiler.misc.illegal.flag.combo: private protected, field, my_field))
+1 error

test/langtools/tools/javac/classreader/8219810/BadMethodFlags.jcod

@@ -0,0 +1,77 @@
+//
+//  class BadMethodFlags {
+//      protected native int my_method();
+//  }
+//
+class BadMethodFlags {
+  0xCAFEBABE;
+  0; // minor version
+  63; // version
+  [] { // Constant Pool
+    ; // first element is empty
+    Method #2 #3; // #1
+    class #4; // #2
+    NameAndType #5 #6; // #3
+    Utf8 "java/lang/Object"; // #4
+    Utf8 "<init>"; // #5
+    Utf8 "()V"; // #6
+    class #8; // #7
+    Utf8 "BadMethodFlags"; // #8
+    Utf8 "Code"; // #9
+    Utf8 "LineNumberTable"; // #10
+    Utf8 "my_method"; // #11
+    Utf8 "()I"; // #12
+    Utf8 "SourceFile"; // #13
+    Utf8 "BadMethodFlags.java"; // #14
+  } // Constant Pool
+
+  0x0020; // access
+  #7;// this_cpx
+  #2;// super_cpx
+
+  [] { // Interfaces
+  } // Interfaces
+
+  [] { // Fields
+  } // Fields
+
+  [] { // Methods
+    {  // method
+      0x0000; // access
+      #5; // name_index
+      #6; // descriptor_index
+      [] { // Attributes
+        Attr(#9) { // Code
+          1; // max_stack
+          1; // max_locals
+          Bytes[]{
+            0x2AB70001B1;
+          }
+          [] { // Traps
+          } // end Traps
+          [] { // Attributes
+            Attr(#10) { // LineNumberTable
+              [] { // line_number_table
+                0  1;
+              }
+            } // end LineNumberTable
+          } // Attributes
+        } // end Code
+      } // Attributes
+    }
+    ;
+    {  // method
+      0x0105; // access *** SHOULD BE 0x0104 ***
+      #11; // name_index
+      #12; // descriptor_index
+      [] { // Attributes
+      } // Attributes
+    }
+  } // Methods
+
+  [] { // Attributes
+    Attr(#13) { // SourceFile
+      #14;
+    } // end SourceFile
+  } // Attributes
+} // end class BadMethodFlags

test/langtools/tools/javac/classreader/8219810/BadMethodFlagsTest.java

@@ -0,0 +1,12 @@
+/*
+ * @test /nodynamiccopyright/
+ * @bug 8219810
+ * @summary Verify ClassReader detects invalid method access flags combinations
+ * @build BadMethodFlags
+ * @compile/fail/ref=BadMethodFlagsTest.out -XDrawDiagnostics BadMethodFlagsTest.java
+ */
+public class BadMethodFlagsTest {
+    {
+        new BadMethodFlags().my_method();
+    }
+}

test/langtools/tools/javac/classreader/8219810/BadMethodFlagsTest.out

@@ -0,0 +1,2 @@
+BadMethodFlagsTest.java:10:13: compiler.err.cant.access: BadMethodFlags, (compiler.misc.bad.class.file.header: BadMethodFlags.class, (compiler.misc.illegal.flag.combo: public protected native, method, my_method()))
+1 error

test/langtools/tools/javac/diags/examples.not-yet.txt

@@ -66,6 +66,7 @@ compiler.misc.fatal.err.cant.locate.meth                # Resolve, from Lower
 compiler.misc.fatal.err.cant.close                      # JavaCompiler
 compiler.misc.feature.not.supported.in.source.plural    # cannot happen (for now)
 compiler.misc.file.does.not.contain.package
+compiler.misc.illegal.flag.combo                        # ClassReader
 compiler.misc.illegal.start.of.class.file
 compiler.misc.inferred.do.not.conform.to.lower.bounds   # cannot happen?
 compiler.misc.kindname.annotation