无法验证使用OpenSSL签名的中间密钥

Question

能否请您看一下代码？我正在尝试创建根ca，然后创建中间ca请求，然后使用根密钥来发出请求：

#!/bin/bash

readonly root_key="ca_key.pem"
readonly root_cert="ca_cert.pem"
readonly int_key="int_key.pem"
readonly int_csr="int_csr.pem"
readonly int_cert="int_cert.pem"

openssl req \
    -x509 \
    -newkey rsa:4096 \
    -keyout "$root_key" \
    -out "$root_cert" \
    -days 3650 \
    -nodes \
    -batch \
    -addext basicConstraints=critical,CA:TRUE,pathlen:1 \
    -subj "/CN=LamaMind Root CA/O=LamaMind"

openssl req \
    -newkey rsa:4096 \
    -keyout "$int_key" \
    -out "$int_csr" \
    -nodes \
    -batch \
    -subj "/CN=LamaMind signing CA/O=LamaMind"

openssl x509 -req \
    -days 3600 \
    -in "$int_csr" \
    -CA "$root_cert" \
    -CAkey "$root_key" \
    -CAcreateserial \
    -out "$int_cert"

openssl verify -CAfile $root_cert $int_cert

最后一行的验证失败，并显示以下消息：

error 24 at 1 depth lookup: invalid CA certificate
error int_cert.pem: verification failed

我做错了什么？