/* Copy from userspace and compute checksum. If we catch an exception then zero the rest of the buffer.  */
__wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *err_ptr)
/* Copy from userspace and compute checksum. If we catch an exception then zero the rest of the buffer.  */
__wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *err_ptr)
{
	int missing;
	missing = copy_from_user(dst, src, len);
	if (missing) {
		memset(dst + len - missing, 0, missing);
		*err_ptr = -EFAULT;
	}
	return csum_partial(dst, len, sum);
}