Program: 43951
Project: 43951
Buggy source:
private void getinfo(LuaState vm){
  LuaState threadVm=vm;
  CallInfo ci=null;
  LFunction func=null;
  LClosure closure=null;
  String what="String_Node_Str";
  if (vm.gettop() >= 4) {
    threadVm=vm.checkthread(2).vm;
    vm.remove(2);
  }
  if (vm.gettop() >= 3) {
    what=vm.tostring(3);
  }
  if (vm.isnumber(2)) {
    ci=this.getcallinfo(vm,threadVm,vm.tointeger(2));
    closure=ci.closure;
  }
 else {
    func=vm.checkfunction(2);
    if (func instanceof LClosure)     closure=(LClosure)func;
  }
  vm.resettop();
  LTable info=new LTable();
  vm.pushlvalue(info);
  for (int i=0, n=what.length(); i < n; i++) {
switch (what.charAt(i)) {
case 'S':
{
        info.put("String_Node_Str",(closure != null ? closure.p.source : new LString("String_Node_Str")));
        info.put("String_Node_Str",(closure != null ? closure.p.source.substring(1,closure.p.source.m_length - 1) : new LString("String_Node_Str")));
        info.put("String_Node_Str",(closure != null ? closure.p.linedefined : 0));
        info.put("String_Node_Str",(closure != null ? closure.p.lastlinedefined : 0));
        info.put("String_Node_Str",new LString(what));
        break;
      }
case 'l':
{
      info.put("String_Node_Str",(ci != null ? ci.pc : 0));
      break;
    }
case 'u':
{
    info.put("String_Node_Str",(closure != null ? closure.p.nups : 0));
    info.put("String_Node_Str",new LString(what));
    break;
  }
case 'n':
{
  info.put("String_Node_Str",new LString("String_Node_Str"));
  info.put("String_Node_Str",new LString("String_Node_Str"));
  break;
}
case 'f':
{
if (func != null) info.put("String_Node_Str",func);
break;
}
case 'L':
{
LTable lines=new LTable();
info.put("String_Node_Str",lines);
if (closure != null) for (int j=0, k=1; j < closure.p.lineinfo.length; j++, k++) lines.put(k,LInteger.valueOf(closure.p.lineinfo[j]));
break;
}
}
}
}

Fixed version (ground truth):
private void getinfo(LuaState vm){
  LuaState threadVm=vm;
  CallInfo ci=null;
  LFunction func=null;
  LClosure closure=null;
  if (vm.gettop() >= 4) {
    threadVm=vm.checkthread(2).vm;
    vm.remove(2);
  }
  String what=vm.optstring(3,"String_Node_Str");
  if (vm.isnumber(2)) {
    ci=this.getcallinfo(vm,threadVm,vm.tointeger(2));
    closure=ci.closure;
  }
 else {
    func=vm.checkfunction(2);
    if (func instanceof LClosure)     closure=(LClosure)func;
  }
  vm.resettop();
  LTable info=new LTable();
  vm.pushlvalue(info);
  for (int i=0, n=what.length(); i < n; i++) {
switch (what.charAt(i)) {
case 'S':
{
        String s=(closure != null ? closure.p.source.toJavaString() : "String_Node_Str");
        info.put("String_Node_Str",new LString(s.replace('@','=')));
        info.put("String_Node_Str",new LString(s.substring(1)));
        info.put("String_Node_Str",(closure != null ? closure.p.linedefined : 0));
        info.put("String_Node_Str",(closure != null ? closure.p.lastlinedefined : 0));
        info.put("String_Node_Str",new LString("String_Node_Str"));
        break;
      }
case 'l':
{
      info.put("String_Node_Str",currentline(threadVm,ci,func));
      break;
    }
case 'u':
{
    info.put("String_Node_Str",(closure != null ? closure.p.nups : 0));
    break;
  }
case 'n':
{
  info.put("String_Node_Str",new LString("String_Node_Str"));
  info.put("String_Node_Str",new LString("String_Node_Str"));
  break;
}
case 'f':
{
info.put("String_Node_Str",closure);
break;
}
case 'L':
{
LTable lines=new LTable();
info.put("String_Node_Str",lines);
for (int j=threadVm.cc, k=1; j >= 0; --j) if (threadVm.calls[j].closure == func) {
int line=threadVm.debugGetLineNumber(ci);
if (line >= 0) lines.put(k++,LInteger.valueOf(line));
}
break;
}
}
}
}