Populating map with new pointers in a loop (C++) - c++

Question

So I am working on the Copy List with Random Pointer question from leetcode and ran into a bit of a problem.
for (; iterateOG->next != nullptr;
iterateOG = iterateOG->next) {
Node* tmp = new Node;
hashTable.insert(std::pair<Node*,Node*>(iterateOG,tmp));
}
So I want to create a new Node object for every existing node in the orginal list. After running the test cases I get an error message like including the HINT below
'hashTable' <== Memory access at offset 912 overflows this variable
HINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext
(longjmp and C++ exceptions *are* supported)
Does anyone know what is causing this problem? I know the cause might be because I created a new object and didn't do anything with it within the scope, but I don't see a solution around this problem. Any help would be appreciated. Thank you!
Full code and error message below
/*
// Definition for a Node.
class Node {
public:
int val;
Node* next;
Node* random;
Node() {}
Node(int _val, Node* _next, Node* _random) {
val = _val;
next = _next;
random = _random;
}
};
*/
class Solution {
public:
Node* copyRandomList(Node* head) {
if (head == nullptr)
return nullptr;
Node* iterateOG = head;
std::map<Node*, Node*> hashTable;
for (; iterateOG->next != nullptr;
iterateOG = iterateOG->next) {
Node* tmp = new Node;
hashTable.insert(std::pair<Node*,Node*>(iterateOG,tmp));
}
std::cout << endl;
iterateOG = head;
for (; iterateOG->next != nullptr;
iterateOG = iterateOG->next) {
hashTable.find(iterateOG)->second->val = iterateOG->val;
hashTable.find(iterateOG)->second->next = hashTable.find(iterateOG->next)->second;
hashTable.find(iterateOG)->second->random = hashTable.find(iterateOG->random)->second;
std::cout << hashTable.find(iterateOG)->second->val << ',';
}
std::cout << endl;
return hashTable.find(head)->second;
}
};
Error Message
=================================================================
==29==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7ffc4dbbbb70 at pc 0x00000041d7eb bp 0x7ffc4dbbb7b0 sp 0x7ffc4dbbb7a8
READ of size 8 at 0x7ffc4dbbbb70 thread T0
#2 0x7fa042ca92e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)
Address 0x7ffc4dbbbb70 is located in stack of thread T0 at offset 912 in frame
This frame has 14 object(s):
[32, 33) '__c'
[96, 97) '__c'
[160, 168) 'iterateOG'
[224, 232) 'tmp'
[288, 296) '<unknown>'
[352, 360) '<unknown>'
[416, 424) '<unknown>'
[480, 488) '<unknown>'
[544, 552) '<unknown>'
[608, 616) '<unknown>'
[672, 680) '<unknown>'
[736, 744) 'head'
[800, 816) '<unknown>'
[864, 912) 'hashTable' <== Memory access at offset 912 overflows this variable
HINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext
(longjmp and C++ exceptions *are* supported)
Shadow bytes around the buggy address:
0x100009b6f710: 00 f2 f2 f2 f2 f2 f2 f2 f8 f2 f2 f2 f2 f2 f2 f2
0x100009b6f720: f8 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 f2 f2 f2 f2
0x100009b6f730: 00 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 f2 f2 f2 f2
0x100009b6f740: 00 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 f2 f2 f2 f2
0x100009b6f750: 00 f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 f2 f2 f2 f2
=>0x100009b6f760: f8 f8 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00[f2]f2
0x100009b6f770: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
0x100009b6f780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x100009b6f790: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x100009b6f7a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x100009b6f7b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Shadow byte legend (one shadow byte represents 8 application bytes):
Addressable: 00
Partially addressable: 01 02 03 04 05 06 07
Heap left redzone: fa
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
Stack after return: f5
Stack use after scope: f8
Global redzone: f9
Global init order: f6
Poisoned by user: f7
Container overflow: fc
Array cookie: ac
Intra object redzone: bb
ASan internal: fe
Left alloca redzone: ca
Right alloca redzone: cb
==29==ABORTING

Answer 1

The bug is on this line:
hashTable.find(iterateOG)->second->next = hashTable.find(iterateOG->next)->second;
For the last node iterateOG->next has value that isn't in hashTable.