filter_rsvd_memory (unsigned long start, unsigned long end, void *arg)
{
	unsigned long range_start, range_end, prev_start;
	void (*func)(unsigned long, unsigned long, int);
	int i;

#if IGNORE_PFN0
	if (start == PAGE_OFFSET) {
		printk(KERN_WARNING "warning: skipping physical page 0\n");
		start += PAGE_SIZE;
		if (start >= end) return 0;
	}
#endif
	/*
	 * lowest possible address(walker uses virtual)
	 */
	prev_start = PAGE_OFFSET;
	func = arg;

	for (i = 0; i < num_rsvd_regions; ++i) {
		range_start = max(start, prev_start);
		range_end   = min(end, rsvd_region[i].start);

		if (range_start < range_end)
			call_pernode_memory(__pa(range_start), range_end - range_start, func);

		/* nothing more available in this segment */
		if (range_end == end) return 0;

		prev_start = rsvd_region[i].end;
	}
	/* end of memory marker allows full processing inside loop body */
	return 0;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.