pointers - Debug error, Heap Corruption? -

] i'm trying free dynamic array , error:

heap corruption detected: after normal block (#65) @ 0x00abd260. crt detected application wrote memory after end of heap buffer.

void mergesort(monom *data,unsigned int size) {     monom *temp = 0;     unsigned int i;     if (size == 1)     {         return;     }     else     {         mergesort(data, (size / 2));         mergesort(data + size / 2, size - size / 2);         temp = (monom*)malloc(size * sizeof(monom*));         if (temp == null)         {             exit(1);         }         sortedmerge(data, data + size / 2, size / 2, size - size / 2, temp);         (i = 0; < size; i++)         {             data[i] = temp[i];         }         free(temp);     } } 

what's wrong it?. thank you!.