static int f2fs_mpage_readpages(struct address_space *mapping,
			struct list_head *pages, struct page *page,
			unsigned nr_pages)
{
	struct bio *bio = NULL;
	unsigned page_idx;
	sector_t last_block_in_bio = 0;
	struct inode *inode = mapping->host;
	const unsigned blkbits = inode->i_blkbits;
	const unsigned blocksize = 1 << blkbits;
	sector_t block_in_file;
	sector_t last_block;
	sector_t last_block_in_file;
	sector_t block_nr;
	struct f2fs_map_blocks map;

	map.m_pblk = 0;
	map.m_lblk = 0;
	map.m_len = 0;
	map.m_flags = 0;
	map.m_next_pgofs = NULL;

	for (page_idx = 0; nr_pages; page_idx++, nr_pages--) {

		prefetchw(&page->flags);
		if (pages) {
			page = list_last_entry(pages, struct page, lru);
			list_del(&page->lru);
			if (add_to_page_cache_lru(page, mapping,
						  page->index,
						  readahead_gfp_mask(mapping)))
				goto next_page;
		}

		block_in_file = (sector_t)page->index;
		last_block = block_in_file + nr_pages;
		last_block_in_file = (i_size_read(inode) + blocksize - 1) >>
								blkbits;
		if (last_block > last_block_in_file)
			last_block = last_block_in_file;

		/*
		 * Map blocks using the previous result first.
		 */
		if ((map.m_flags & F2FS_MAP_MAPPED) &&
				block_in_file > map.m_lblk &&
				block_in_file < (map.m_lblk + map.m_len))
			goto got_it;

		/*
		 * Then do more f2fs_map_blocks() calls until we are
		 * done with this page.
		 */
		map.m_flags = 0;

		if (block_in_file < last_block) {
			map.m_lblk = block_in_file;
			map.m_len = last_block - block_in_file;

			if (f2fs_map_blocks(inode, &map, 0,
						F2FS_GET_BLOCK_READ))
				goto set_error_page;
		}
got_it:
		if ((map.m_flags & F2FS_MAP_MAPPED)) {
			block_nr = map.m_pblk + block_in_file - map.m_lblk;
			SetPageMappedToDisk(page);

			if (!PageUptodate(page) && !cleancache_get_page(page)) {
				SetPageUptodate(page);
				goto confused;
			}
		} else {
			zero_user_segment(page, 0, PAGE_SIZE);
			if (!PageUptodate(page))
				SetPageUptodate(page);
			unlock_page(page);
			goto next_page;
		}

		/*
		 * This page will go to BIO.  Do we need to send this
		 * BIO off first?
		 */
		if (bio && (last_block_in_bio != block_nr - 1 ||
			!__same_bdev(F2FS_I_SB(inode), block_nr, bio))) {
submit_and_realloc:
			__submit_bio(F2FS_I_SB(inode), bio, DATA);
			bio = NULL;
		}
		if (bio == NULL) {
			bio = f2fs_grab_bio(inode, block_nr, nr_pages);
			if (IS_ERR(bio)) {
				bio = NULL;
				goto set_error_page;
			}
			bio_set_op_attrs(bio, REQ_OP_READ, 0);
		}

		if (bio_add_page(bio, page, blocksize, 0) < blocksize)
			goto submit_and_realloc;

		last_block_in_bio = block_nr;
		goto next_page;
set_error_page:
		SetPageError(page);
		zero_user_segment(page, 0, PAGE_SIZE);
		unlock_page(page);
		goto next_page;
confused:
		if (bio) {
			__submit_bio(F2FS_I_SB(inode), bio, DATA);
			bio = NULL;
		}
		unlock_page(page);
next_page:
		if (pages)
			put_page(page);
	}
	BUG_ON(pages && !list_empty(pages));
	if (bio)
		__submit_bio(F2FS_I_SB(inode), bio, DATA);
	return 0;
}

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.