Переполнение буфера

#pragma once
#include <iostream>
#include <stdlib.h>
#include <fstream>
#include "bmp_structs.h"
using namespace std;
 
class BMP
{
public:
    BitMapHeader bh;
    BitMapInfoHeader bih;
    RGBQUAD RGBQuad[256];
    BMP();
    void ReadQuad(RGBQUAD* RGB, int biSize, char* filename);
    void France_flag(char* filename);
 
    BMP read_BMP_info(char* filename);
    
    
    friend struct BitMapHeader;
    friend struct BitMapInfoHeader;
    friend struct RGBQUAD;
    ~BMP();
    
    
};

#include "StdAfx.h"
#include "BMP.h"
 
 
BMP::BMP()
{
}
 
 
void BMP::ReadQuad(tagRGBQUAD* RGB, int biSize, char* filename)
{
    fstream f(filename, ios::binary | ios::out | ios::in | ios::ate);
    f.seekg(biSize, SEEK_SET);
    f.read((char*)& RGB, 1024);
    f.close();
}
BMP BMP::read_BMP_info(char* filename)
{
    BMP h;
    fstream f(filename,ios::binary | ios::out | ios::in | ios::ate);
    f.seekg(0, ios::beg);
    f.read((char*)& h.bh,sizeof(bh));
    f.read((char*)& h.bih,sizeof(bih));
    h.ReadQuad(RGBQuad, h.bih.biSize + 14, filename);
    f.close();
    return h;
}
void BMP::France_flag(char* filename)
{
    BMP h;
    fstream f(filename, ios::binary | ios::out | ios::in | ios::ate);
    h.read_BMP_info(filename);
    f.seekg(h.bh.bfOffbits + 14, ios::beg);
    int n = h.bih.biHeight / 3;
    int m = h.bih.biWidth;
    tagRGBQUAD* part1 = new tagRGBQUAD [n * m] ;
    tagRGBQUAD* part2 = new tagRGBQUAD [n * m];
    tagRGBQUAD* part3 = new tagRGBQUAD [n * m];
    for(int i = 0; i < n * m; i ++)
    {
        part1[i].rgbBlue = 255;
        part2[i].rgbBlue = 255;
        part3[i].rgbBlue = 0;
        part1[i].rgbGreen = 255;
        part2[i].rgbGreen = 0;
        part3[i].rgbGreen = 0;
        part1[i].rgbRed = 255;
        part2[i].rgbRed = 0;
        part1[i].rgbRed = 255;
    }
    f.seekg(h.bh.bfOffbits + 14, ios::beg);
    f.write((char*)& part1, sizeof(part1));
    f.write((char*)& part2, sizeof(part2));
    f.write((char*)& part3, sizeof(part3));
    f.close();
    
    
}
BMP::~BMP()
{
}

typedef unsigned short int word; 
typedef unsigned int dword;
#pragma pack(push)
#pragma pack(1)
 
struct BitMapHeader
{
word bfType; 
dword bfSize; 
word bfReserved1;  
word bfReserved2;  
dword bfOffbits; 
};
 
struct BitMapInfoHeader
{
dword biSize ; 
dword biWidth;
dword biHeight; 
word biPlanes;
word biBitCount;  
dword biCompression; 
dword biSizeImage; 
dword biXPelPerMeter; 
dword biYPelPerMeter;  
dword biClrUsed;  
dword biClrImportant;
};
typedef unsigned char BYTE;
 
#pragma pack(pop)
 
struct RGBQUAD {
BYTE rgbBlue;
BYTE rgbGreen;
BYTE rgbRed;
BYTE rgbReserved;
};

 int n = h.bih.biHeight / 3;
    int m = h.bih.biWidth;
    tagRGBQUAD* part1 = new tagRGBQUAD [n * m] ;
    tagRGBQUAD* part2 = new tagRGBQUAD [n * m];
    tagRGBQUAD* part3 = new tagRGBQUAD [n * m];

void BMP::France_flag(char* filename)
{
    BMP h;
    fstream f(filename, ios::binary | ios::out | ios::in);
    h.read_BMP_info(filename);
    
    
    unsigned int n = h.bih.biHeight;
    unsigned int m = h.bih.biWidth;
    
    BYTE* Str = new BYTE [m];
    for(int i = 0; i < m / 3; i ++)
        Str[i] = 0xCC;
    for(int i = m / 3; i < 2 * (m / 3); i ++)
        Str[i] = 0xFF;
    for(int i = 2 * (m / 3); i < m; i ++)
        Str[i] = 0x99;
 
    f.seekg(h.bh.bfOffbits, ios::beg);
    int counter = 0;
    while(counter != h.bih.biHeight)
    {
        f.write((char*)Str, h.bih.biWidth);
        counter ++;
    }
    
    f.close();
    
    
}