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#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>

// BUGGY

int main(int argc, char* argv[]) {
    char* s = malloc(sizeof(*s) * 4);
    s[0] = 'A';  // first byte inside buffer (=block)
    s[1] = 'B';
    s[2] = 'C';
    s[3] = 'D';  // last byte inside buffer (=block)
    s[4] = 'E';  // BUG: Invalid write of size 1 … 0 bytes after a block of size 4 alloc'd
    s[5] = '\0'; // BUG: Invalid write of size 1 … 1 bytes after a block of size 4 alloc'd

    free(s);

    // PROBLEM: We tried to write to memory after the call to free(…).
    s[0] = 'Z';   // BUG!!!  Invalid write of size 1 after block … free'd
    
    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */


/*

*/

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