#fixed code
                                public int confstr(Confstr name, ByteBuffer buf, int len) {
        return posix().confstr(name, buf, len);
    }
#vulnerable code 
                                public int confstr(Confstr name, ByteBuffer buf, int len) {
        return libc().confstr(name, buf, len);
    } 
                            #location 2 
                            #vulnerability type NULL_DEREFERENCE