static int ubifs_do_bulk_read(struct ubifs_info *c, struct bu_info *bu,
			      struct page *page1)
{
	pgoff_t offset = page1->index, end_index;
	struct address_space *mapping = page1->mapping;
	struct inode *inode = mapping->host;
	struct ubifs_inode *ui = ubifs_inode(inode);
	int err, page_idx, page_cnt, ret = 0, n = 0;
	int allocate = bu->buf ? 0 : 1;
	loff_t isize;

	err = ubifs_tnc_get_bu_keys(c, bu);
	if (err)
		goto out_warn;

	if (bu->eof) {
		/* Turn off bulk-read at the end of the file */
		ui->read_in_a_row = 1;
		ui->bulk_read = 0;
	}

	page_cnt = bu->blk_cnt >> UBIFS_BLOCKS_PER_PAGE_SHIFT;
	if (!page_cnt) {
		/*
		 * This happens when there are multiple blocks per page and the
		 * blocks for the first page we are looking for, are not
		 * together. If all the pages were like this, bulk-read would
		 * reduce performance, so we turn it off for a while.
		 */
		goto out_bu_off;
	}

	if (bu->cnt) {
		if (allocate) {
			/*
			 * Allocate bulk-read buffer depending on how many data
			 * nodes we are going to read.
			 */
			bu->buf_len = bu->zbranch[bu->cnt - 1].offs +
				      bu->zbranch[bu->cnt - 1].len -
				      bu->zbranch[0].offs;
			ubifs_assert(bu->buf_len > 0);
			ubifs_assert(bu->buf_len <= c->leb_size);
			bu->buf = kmalloc(bu->buf_len, GFP_NOFS | __GFP_NOWARN);
			if (!bu->buf)
				goto out_bu_off;
		}

		err = ubifs_tnc_bulk_read(c, bu);
		if (err)
			goto out_warn;
	}

	err = populate_page(c, page1, bu, &n);
	if (err)
		goto out_warn;

	unlock_page(page1);
	ret = 1;

	isize = i_size_read(inode);
	if (isize == 0)
		goto out_free;
	end_index = ((isize - 1) >> PAGE_CACHE_SHIFT);

	for (page_idx = 1; page_idx < page_cnt; page_idx++) {
		pgoff_t page_offset = offset + page_idx;
		struct page *page;

		if (page_offset > end_index)
			break;
		page = find_or_create_page(mapping, page_offset,
					   GFP_NOFS | __GFP_COLD);
		if (!page)
			break;
		if (!PageUptodate(page))
			err = populate_page(c, page, bu, &n);
		unlock_page(page);
		page_cache_release(page);
		if (err)
			break;
	}

	ui->last_page_read = offset + page_idx - 1;

out_free:
	if (allocate)
		kfree(bu->buf);
	return ret;

out_warn:
	ubifs_warn("ignoring error %d and skipping bulk-read", err);
	goto out_free;

out_bu_off:
	ui->read_in_a_row = ui->bulk_read = 0;
	goto out_free;
}

This category addresses vulnerabilities caused by flawed access control mechanisms, where incorrect permission settings allow unauthorized users to access restricted resources.