asmlinkage long compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg,
				    unsigned int vlen, unsigned int flags,
				    struct compat_timespec __user *timeout)
{
	int datagrams;
	struct timespec ktspec;

 	if (flags & MSG_CMSG_COMPAT)
 		return -EINVAL;
 
 	if (timeout == NULL)
 		return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
 				      flags | MSG_CMSG_COMPAT, NULL);
 
	if (compat_get_timespec(&ktspec, timeout))
 		return -EFAULT;
 
 	datagrams = __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
 				   flags | MSG_CMSG_COMPAT, &ktspec);
	if (datagrams > 0 && compat_put_timespec(&ktspec, timeout))
 		datagrams = -EFAULT;
 
 	return datagrams;
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.