[BCEL-311] ClassCastException in Verifier Pass 2

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 6.2
• Fix Version/s: 6.8.0
• Component/s: Verifier
• Assignee: Unassigned
• Reporter: Rohan Padhye
• Created: 23/Aug/18 02:52
• Updated: 17/Jun/23 18:16
• Resolved: 17/Jun/23 18:16

Description

Verifier throws ClassCastException on malformed input instead of reporting verification failure.

Steps to reproduce:

 

Save the attached file as "Hello.class" and run:

java -cp <classpath> org.apache.bcel.verifier.Verifier Hello

 

The file Hello.class was generated automatically by the fuzzer JQF (https://github.com/rohanpadhye/jqf).

Expected output:

VERIFIED_REJECTED

Observed output:

JustIce by Enver Haase, (C) 2001-2002.

<http://bcel.sourceforge.net>

<http://commons.apache.org/bcel>

 

Now verifying: Hello

 

Pass 1:

VERIFIED_OK

Passed verification.

 

Exception in thread "main" java.lang.ClassCastException: Illegal constant 'CONSTANT_Class[7](name_index = 21)' at index '5'. '<<Method>>' expects a 'class org.apache.bcel.classfile.ConstantUtf8'.

at org.apache.bcel.verifier.statics.Pass2Verifier$CPESSC_Visitor.checkIndex(Pass2Verifier.java:372)

at org.apache.bcel.verifier.statics.Pass2Verifier$CPESSC_Visitor.visitMethod(Pass2Verifier.java:622)

at org.apache.bcel.classfile.Method.accept(Method.java:108)

at org.apache.bcel.classfile.DescendingVisitor.visitMethod(DescendingVisitor.java:159)

at org.apache.bcel.classfile.Method.accept(Method.java:108)

at org.apache.bcel.classfile.DescendingVisitor.visitJavaClass(DescendingVisitor.java:99)

at org.apache.bcel.classfile.JavaClass.accept(JavaClass.java:213)

at org.apache.bcel.classfile.DescendingVisitor.visit(DescendingVisitor.java:85)

at org.apache.bcel.verifier.statics.Pass2Verifier$CPESSC_Visitor.<init>(Pass2Verifier.java:361)

at org.apache.bcel.verifier.statics.Pass2Verifier$CPESSC_Visitor.<init>(Pass2Verifier.java:317)

at org.apache.bcel.verifier.statics.Pass2Verifier.constant_pool_entries_satisfy_static_constraints(Pass2Verifier.java:302)

at org.apache.bcel.verifier.statics.Pass2Verifier.do_verify(Pass2Verifier.java:161)

at org.apache.bcel.verifier.PassVerifier.verify(PassVerifier.java:71)

at org.apache.bcel.verifier.Verifier.doPass2(Verifier.java:76)

at org.apache.bcel.verifier.Verifier.main(Verifier.java:211)