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The above code examples perform the same when working with vectors.

enum { TABLESIZE = 100 };

vector<int> table;

int insert_in_table(int pos, int value){
  if (pos >= table.size()) {
    return -1;
  }
  table[pos] = value;
  return 0;
}

The function performs a range check to ensure that pos does not exceed the upper bound of the array but fails to check the lower bound for table. Because pos has been declared as a (signed) int, this parameter can easily assume a negative value, resulting in a write outside the bounds of the memory referenced by table.

Compliant Solution (

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Vectors, size_t)

In this compliant solution, the parameter pos is declared as size_t, which prevents passing of negative arguments (see INT01-CPP. Use rsize_t or size_t for all integer values representing the size of an object).

enum { TABLESIZE = 100 };

vector<int> table;

int insert_in_table(size_t pos, int value){
  if (pos >= table.size()) {
    return -1;
  }
  table[pos] = value;
  return 0;
}

Compliant Solution (Vectors, at())

In this compliant solution, access to the vector is accomplished with the at() method. This method provides bounds checking, throwing an out_of_range exception if pos is not a valid index value.

vector<int> table;

int insert_in_table(size_t pos, int value){
  table.at(pos) = value;
  return 0;
}

Risk Assessment

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