Command & Conquer

270599

Suspicious formatting

V705 It is possible that ‘else’ block was forgotten or commented out, thus altering the program’s operation logics. NETDLG.CPP 1506

static int Net_Join_Dialog(void)
{
  ....
  /*...............................................................
  F4/SEND/'M' = edit a message
  ...............................................................*/
  if (Messages.Get_Edit_Buf()==NULL) {
    ....
  } else  /*...............................................................
  If we're already editing a message and the user clicks on
  'Send', translate our input to a Return so Messages.Input() will
  work properly.
  ...............................................................*/
  if (input==(BUTTON_SEND | KN_BUTTON)) {
    input = KN_RETURN;
  }
  ....
}

Due to a large comment, the developer hasn’t seen the above unfinished conditional operator. The remaining else keyword forms the else if construction with the condition below, which most likely changes the original logic.

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Ghidra

Ghidra

Always true & Unreachable code

public void setValueAt(Object aValue, int row, int column) {
  ...
  int index = indexOf(newName);
  if (index >= 0) {                  // <=
    Window window = tool.getActiveWindow();
    Msg.showInfo(getClass(), window, "Duplicate Name",
                 "Name already exists: " + newName);
    return;
  }

  ExternalPath path = paths.get(row); // <=
  ...
}
private int indexOf(String name) {
  for (int i = 0; i < paths.size(); i++) {
    ExternalPath path = paths.get(i);
    if (path.getName().equals(name)) {
      return i;
    }
  }
  return 0;
}

PVS-Studio warnings:

  • V6007 Expression ‘index >= 0’ is always true. ExternalNamesTableModel.java:105
  • V6019 Unreachable code detected. It is possible that an error is present. ExternalNamesTableModel.java:109

Something distracted the developer, and they accidentally implemented the indexOf method in such a way that it returns 0, i.e. the index of the first element of the paths collection, instead of -1 for a non-existent value. This will happen even if the collection is empty. Or maybe they generated the method but forgot to change the default return value. Anyway, the setValueAt method will refuse any offered value and show the message “Name already exists” even if there’s not a single name in the collection.

By the way, the indexOf method is not used anywhere else, and its value is actually needed only to determine if the sought element exists. Rather than writing a separate method and playing around with indexes, it would probably be better to write a for-each loop right in the setValueAt method and have it return when encountering the matching element.

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Command & Conquer

270599

Array overrun

V557 Array overrun is possible. The ‘QuantityB’ function processes value ‘[0..86]’. Inspect the first argument. Check lines: ‘HOUSE.H:928’, ‘CELL.CPP:2337’. HOUSE.H 928

typedef enum StructType : char {
  STRUCT_NONE=-1,
  ....
  STRUCT_COUNT,   // <= 87
  STRUCT_FIRST=0
} StructType;
int BQuantity[STRUCT_COUNT-3];
int QuantityB(int index) {return(BQuantity[index]);}
bool CellClass::Goodie_Check(FootClass * object)
{
  ....
  int bcount = 0;
  for( j=0; j < STRUCT_COUNT; j++) {     bcount += hptr->QuantityB(j);
  }
  ....
}

There are a lot of global variables in the code and it is obvious that they are easy to get confused. The analyzer’s warning about an array index out of bounds is issued at the point of accessing the BQuantity array by index. The array size is 84 elements. Algorithms for analyzing the data flow in the analyzer helped to find out that the index value comes from another function – Goodie_Check. There, a loop is executed with a final value of 86. Therefore, 12 bytes of “someone’s” memory (3 int elements) are constantly being read in this place.

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Kodi

Kodi

Missed semicolon

PVS-Studio warning: V504 It is highly probable that the semicolon ‘;’ is missing after ‘return’ keyword. AdvancedSettings.cpp:1476

void CAdvancedSettings::SetExtraArtwork(const TiXmlElement* arttypes,
   std::vector& artworkMap)
{
  if (!arttypes)
    return
  artworkMap.clear();
  const TiXmlNode* arttype = arttypes->FirstChild("arttype");
  ....
}

The code formatting suggests the following execution logic:

  • if arttypes is a null pointer, the method returns;
  • if arttypes is a non-null pointer, the artworkMap vector gets cleared and some actions are then performed.

But the missing ‘;’ character breaks it all, and the actual execution logic is as follows:

  • if arttypes is a null pointer, the artworkMap vector gets cleared and the method returns;
  • if arttypes is a non-null pointer, the program executes whatever actions come next but the artworkMap vector doesn’t get cleared.

To cut a long story short, this situation does look like a bug. After all, you hardly expect anyone to write expressions like return artworkMap.clear(); :).

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