static int cifs_copy_posix_acl(char *trgt, char *src, const int buflen,
			       const int acl_type, const int size_of_data_area)
{
	int size =  0;
	int i;
	__u16 count;
	struct cifs_posix_ace *pACE;
	struct cifs_posix_acl *cifs_acl = (struct cifs_posix_acl *)src;
	posix_acl_xattr_header *local_acl = (posix_acl_xattr_header *)trgt;

	if (le16_to_cpu(cifs_acl->version) != CIFS_ACL_VERSION)
		return -EOPNOTSUPP;

	if (acl_type & ACL_TYPE_ACCESS) {
		count = le16_to_cpu(cifs_acl->access_entry_count);
		pACE = &cifs_acl->ace_array[0];
		size = sizeof(struct cifs_posix_acl);
		size += sizeof(struct cifs_posix_ace) * count;
		/* check if we would go beyond end of SMB */
		if (size_of_data_area < size) {
			cFYI(1, "bad CIFS POSIX ACL size %d vs. %d",
				size_of_data_area, size);
			return -EINVAL;
		}
	} else if (acl_type & ACL_TYPE_DEFAULT) {
		count = le16_to_cpu(cifs_acl->access_entry_count);
		size = sizeof(struct cifs_posix_acl);
		size += sizeof(struct cifs_posix_ace) * count;
/* skip past access ACEs to get to default ACEs */
		pACE = &cifs_acl->ace_array[count];
		count = le16_to_cpu(cifs_acl->default_entry_count);
		size += sizeof(struct cifs_posix_ace) * count;
		/* check if we would go beyond end of SMB */
		if (size_of_data_area < size)
			return -EINVAL;
	} else {
		/* illegal type */
		return -EINVAL;
	}

	size = posix_acl_xattr_size(count);
	if ((buflen == 0) || (local_acl == NULL)) {
		/* used to query ACL EA size */
	} else if (size > buflen) {
		return -ERANGE;
	} else /* buffer big enough */ {
		local_acl->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION);
		for (i = 0; i < count ; i++) {
			cifs_convert_ace(&local_acl->a_entries[i], pACE);
			pACE++;
		}
	}
	return size;
}

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.