static int fuse_readpage(struct file *file, struct page *page)
{
	struct inode *inode = page->mapping->host;
	struct fuse_conn *fc = get_fuse_conn(inode);
	struct fuse_req *req;
	size_t num_read;
	loff_t pos = page_offset(page);
	size_t count = PAGE_CACHE_SIZE;
	u64 attr_ver;
	int err;

	err = -EIO;
	if (is_bad_inode(inode))
		goto out;

	/*
	 * Page writeback can extend beyond the liftime of the
	 * page-cache page, so make sure we read a properly synced
	 * page.
	 */
	fuse_wait_on_page_writeback(inode, page->index);

	req = fuse_get_req(fc);
	err = PTR_ERR(req);
	if (IS_ERR(req))
		goto out;

	attr_ver = fuse_get_attr_version(fc);

	req->out.page_zeroing = 1;
	req->out.argpages = 1;
	req->num_pages = 1;
	req->pages[0] = page;
	num_read = fuse_send_read(req, file, pos, count, NULL);
	err = req->out.h.error;
	fuse_put_request(fc, req);

	if (!err) {
		/*
		 * Short read means EOF.  If file size is larger, truncate it
		 */
		if (num_read < count)
			fuse_read_update_size(inode, pos + num_read, attr_ver);

		SetPageUptodate(page);
	}

	fuse_invalidate_attr(inode); /* atime changed */
 out:
	unlock_page(page);
	return err;
}

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.