static struct udf_bitmap *udf_sb_alloc_bitmap(struct super_block *sb, u32 index)
{
	struct udf_bitmap *bitmap;
	int nr_groups;
	int size;

	nr_groups = udf_compute_nr_groups(sb, index);
	size = sizeof(struct udf_bitmap) +
		(sizeof(struct buffer_head *) * nr_groups);

	if (size <= PAGE_SIZE)
		bitmap = kzalloc(size, GFP_KERNEL);
	else
		bitmap = vzalloc(size); /* TODO: get rid of vzalloc */

	if (bitmap == NULL)
		return NULL;

	bitmap->s_block_bitmap = (struct buffer_head **)(bitmap + 1);
	bitmap->s_nr_groups = nr_groups;
	return bitmap;
}

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.