ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
				unsigned long nr_segs, loff_t pos)
{
	ssize_t written;
	struct inode *inode;

	inode = file_inode(iocb->ki_filp);

	/*
	 * BB - optimize the way when signing is disabled. We can drop this
	 * extra memory-to-memory copying and use iovec buffers for constructing
	 * write request.
	 */

	written = cifs_iovec_write(iocb->ki_filp, iov, nr_segs, &pos);
	if (written > 0) {
		CIFS_I(inode)->invalid_mapping = true;
		iocb->ki_pos = pos;
	}

	return written;
}

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.