#include <stdlib.h>
#include <stdio.h>
#include <string.h>

char buffer[16];

int main(int argc, char **argv) {
    if(argc < 2) {
        printf("no parameters specified\n");
        exit(-1);
    }

    char* allocated = malloc(32);
    strcpy(allocated, "test");

    printf("buffer address     = %p\n", buffer);
    printf("allocated address  = %p\n", allocated);
    printf("allocated address - buffer address = %lu\n", allocated - buffer);
    printf("allocated (before) = %s\n", allocated);

    // global buffer overflow may occur here
    // if argv[1] has more than 16 symbols
    strcpy(buffer, argv[1]);

    printf("allocated (after) = %s\n", allocated);

    free(allocated);
}