c
// Vulnerable Code
int result = BN_cmp(dsa->p, some_other_bignum); 

// Patched Code
int result;
if (dsa->p != NULL) {
    result = BN_cmp(dsa->p, some_other_bignum);
} else {
    // Handle error: dsa->p is NULL
    *ret = -1; // Example error code
    return 0;
} 
