how to handle bad pointer

BITMAPINFOHEADER* ReadImage(char* szFileName)
{
	size_t nSize = 0;
	size_t nRead = 0;
	size_t nHeaderSize = 14;
	BITMAPINFOHEADER* pBitmap = NULL;
	// try to open the file.
	FILE* fp=fopen(szFileName, "rb");
	if (fp==NULL)
	{
		printf("%s: failed to open with errno %d.\n", szFileName, errno);
		return NULL;
	}
 
	// get the size if the bitmap
	fseek(fp, 0, SEEK_END);
	nSize = ftell(fp);
	fseek(fp, (long)nHeaderSize, SEEK_SET ); // really dirty skip the bitmap file header.
	nSize -= nHeaderSize; // adjust the size to fit the mem size

	// get the memory for the bitmap.
	pBitmap = (BITMAPINFOHEADER*)malloc(nSize);
	if (pBitmap==NULL)
	{
		printf("%s: failed to alloc memory.\n", szFileName);
		fclose(fp);
		return NULL;
	}
 
	// read data from disk
	nRead = fread(pBitmap, 1, nSize, fp);
	if (nRead!=nSize)
	{
		free(pBitmap);
		printf("%s: failed to read image.\n", szFileName);
		fclose(fp);
		return NULL;
	}
	
	fclose(fp);
        // You can't free this parameter, because you use argv array item here
	//free((void*)szFileName); 
	return pBitmap;
}

void main( int argc, char *argv[])
{
	DrmErrorCode_t nRetCode;
	FC3Template_t hTemplate1, hTemplate2;
	FC3Encode_t hEncoder;
	FC3Match_t hMatcher;
	double dScore;
	char image1[]={'a'};
	char image2[]={'h'};
 
        scanf("%s",&image1);
 
	// Checking the arguments
	if (argc!=3)
	{
		printf("Usage: %s Image1.bmp, Image2.bmp\n", argv[0]);
		//return 1;
	}
 
	// Loading the image for quality check
	BITMAPINFOHEADER* pBitmap1 = NULL;
	BITMAPINFOHEADER* pBitmap2 = NULL;
	pBitmap1 = ReadImage(argv[0]);
	if (pBitmap1==NULL)
	{
		printf("Error while reading Image1\n");
	}
 
	scanf("%s",&image2);
        pBitmap2 = ReadImage(argv[1]);
	if (pBitmap2==NULL)
	{
		printf("Error while reading Image2\n");
	}
        // You need to free memory used by bitmaps
        free(pBitmap1);
        free(pBitmap2);
}