CRYPTOerr(CRYPTO_F_CRYPTO_DUP_EX_DATA, ERR_R_MALLOC_FAILURE);
return 0;
}
- if (!CRYPTO_set_ex_data(to, mx - 1, NULL))
+ /*
+ * Make sure the ex_data stack is at least |mx| elements long to avoid
+ * issues in the for loop that follows; so go get the |mx|'th element
+ * (if it does not exist CRYPTO_get_ex_data() returns NULL), and assign
+ * to itself. This is normally a no-op; but ensures the stack is the
+ * proper size
+ */
+ if (!CRYPTO_set_ex_data(to, mx - 1, CRYPTO_get_ex_data(to, mx - 1)))
goto err;
for (i = 0; i < mx; i++) {