static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
			       size_t *nbytesp, int write)
{
	size_t nbytes = 0;  /* # bytes already packed in req */

	/* Special case for kernel I/O: can copy directly into the buffer */
	if (ii->type & ITER_KVEC) {
		unsigned long user_addr = fuse_get_user_addr(ii);
		size_t frag_size = fuse_get_frag_size(ii, *nbytesp);

		if (write)
			req->in.args[1].value = (void *) user_addr;
		else
			req->out.args[0].value = (void *) user_addr;

		iov_iter_advance(ii, frag_size);
		*nbytesp = frag_size;
		return 0;
	}

	while (nbytes < *nbytesp && req->num_pages < req->max_pages) {
		unsigned npages;
		size_t start;
		ssize_t ret = iov_iter_get_pages(ii,
					&req->pages[req->num_pages],
					*nbytesp - nbytes,
					req->max_pages - req->num_pages,
					&start);
		if (ret < 0)
			return ret;

		iov_iter_advance(ii, ret);
		nbytes += ret;

		ret += start;
		npages = (ret + PAGE_SIZE - 1) / PAGE_SIZE;

		req->page_descs[req->num_pages].offset = start;
		fuse_page_descs_length_init(req, req->num_pages, npages);

		req->num_pages += npages;
		req->page_descs[req->num_pages - 1].length -=
			(PAGE_SIZE - ret) & (PAGE_SIZE - 1);
	}

	if (write)
		req->in.argpages = 1;
	else
		req->out.argpages = 1;

	*nbytesp = nbytes;

	return 0;
}

This vulnerability category highlights issues in resource management where failures to properly release memory, file handles, or other resources can degrade system performance or enable denial-of-service conditions.