下面的代码片段用于反转单链表，请进行（ ）修改，使其能正确实现相应功能。
1 ListNode* reverseLinkedList(ListNode* head) {
2 ListNode* prev = nullptr;
3 ListNode* current = head;
4 while (current != nullptr) {
5 ListNode* next = current->next;
6 current->next = next;
7 prev = current;
8 current = next;
9 }
10 return prev;
11 }