isBootRecord(struct iso9660 *iso9660, const unsigned char *h)
{
	(void)iso9660; /* UNUSED */

	/* Type of the Volume Descriptor Boot Record must be 0. */
	if (h[0] != 0)
		return (0);

	/* Volume Descriptor Version must be 1. */
	if (h[6] != 1)
		return (0);

	return (1);
}

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.