cifs_readdata_to_iov(struct cifs_readdata *rdata, const struct iovec *iov,
			unsigned long nr_segs, loff_t offset, ssize_t *copied)
{
	int rc = 0;
	struct iov_iter ii;
	size_t pos = rdata->offset - offset;
	ssize_t remaining = rdata->bytes;
	unsigned char *pdata;
	unsigned int i;

	/* set up iov_iter and advance to the correct offset */
	iov_iter_init(&ii, iov, nr_segs, iov_length(iov, nr_segs), 0);
	iov_iter_advance(&ii, pos);

	*copied = 0;
	for (i = 0; i < rdata->nr_pages; i++) {
		ssize_t copy;
		struct page *page = rdata->pages[i];

		/* copy a whole page or whatever's left */
		copy = min_t(ssize_t, remaining, PAGE_SIZE);

		/* ...but limit it to whatever space is left in the iov */
		copy = min_t(ssize_t, copy, iov_iter_count(&ii));

		/* go while there's data to be copied and no errors */
		if (copy && !rc) {
			pdata = kmap(page);
			rc = memcpy_toiovecend(ii.iov, pdata, ii.iov_offset,
						(int)copy);
			kunmap(page);
			if (!rc) {
				*copied += copy;
				remaining -= copy;
				iov_iter_advance(&ii, copy);
			}
		}
	}

	return rc;
}

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.