ESP32 Arduino: Guru Meditation Error: Core 1 panic'ed (StoreProhibited) - dynamic

Question

Sending data from (mesh network)smoke sensors to AWS. I am storing the node data using linked list.After passing data to AWS,i am try to de-allocate the memory and coming across following two errors in free().
#include <stdio.h>
#include<stdlib.h>
typedef struct Node
{
uint8_t node_data[15]; //stores node infomation
struct Node* next; //pointer to next node
}node;
node *head=NULL;
node*current=NULL;
static uint8_t k[15]; //this array keeps track of data received on UART port
static uint8_t node_count=0; //keeps the track of no. of nodes added to the system
void push_data(int []); /*this function pushes data present in array into
a node(memory allocated to node dynamically)*/
void delete_node(node*); //this function deletes the memory allocated to node
void pack_data(void); // send node data to aws
void loop()
{
if(Serial2.available()>0)
{
for( uint8_t i=0;i<15;i++)
{
k [i]= Serial2.read();
}
push_data(k);
}
delay(5000);
}
void push_data(uint8_t arr[])
{
if(head==NULL)
{
head=(node*)malloc(sizeof(node));
current=(node*)malloc(sizeof(node));
for(uint8_t i=0;i<15;i++)
{
head->node_data[i]=arr[i];
}
head->next=current;
node_count++;
return;
}
else
{
for(uint8_t i=0;i<15;i++)
{
current->node_data[i]=arr[i];
}
current->next=(struct Node*)malloc(sizeof(struct Node));
current=current->next;
current->next=NULL;
node_count++;
pack_data();
return;
}
}
void pack_data()
{
/*this function converts node data into data format
* and sends the data to aws.*/
/* Once the data is send to aws ,
the memory allocated to nodes is freed
*/
delete_node(head);
return;
}
void delete_node(node* n)
{
node* m=NULL;
while(n!=NULL)
{
m=n->next;
free(n);
n=NULL;
n = m;
}
// return;
}
Whenever is am trying to free the dynamically allocated memory,the delete_node function causes problem.Throwing the following errors
ERROR 1
assert failed: multi_heap_realloc multi_heap_poisoning.c:289 (head != NULL)
ERROR 2
Guru Meditation Error: Core 1 panic'ed (LoadStoreError). Exception was unhandled.
Core 1 register dump:
PC : 0x400f3fc4 PS : 0x00060330 A0 : 0x800efca4 A1 : 0x3ffb1920
A2 : 0x00000000 A3 : 0x3ffcc800 A4 : 0x00000005 A5 : 0x00000000
A6 : 0x00000005 A7 : 0x40000014 A8 : 0x800f3ff4 A9 : 0x3ffb1910
A10 : 0x3ffcc800 A11 : 0x88000028 A12 : 0x00000000 A13 : 0x3ffcc800
A14 : 0x00000008 A15 : 0x00000000 SAR : 0x00000004 EXCCAUSE: 0x00000003
EXCVADDR: 0x4000001e LBEG : 0x40088f8c LEND : 0x40088fa2 LCOUNT : 0xffffffff