What were you trying to do that didn't work?

When Apache is configured with mod_ratelimit to limit access speed, GET request is normal, but HEAD request returns error: curl: (52) Empty reply from server

Please help investigate whether this bug affects the rhel version of apache httpd. Thank you very much.

What is the impact of this issue to you?

Unable to obtain header information.

Please provide the package NVR for which the bug is seen:

httpd-2.4.37-65.module+el8.10.0+22756+938009b1.3.x86_64

How reproducible is this bug?:

Everytime.

Steps to reproduce

1. Config httpd.conf and restart service.

```

<Location "/">

    SetOutputFilter RATE_LIMIT

    SetEnv rate-limit 400

</Location>

```

1. Use curl command for test.

```

1. curl -I -vv localhost

• Rebuilt URL to: localhost/

•   Trying ::1...

• TCP_NODELAY set

• Connected to localhost (::1) port 80 (#0)

> HEAD / HTTP/1.1

> Host: localhost

> User-Agent: curl/7.61.1

> Accept: /

>

• Empty reply from server

• Connection #0 to host localhost left intact

curl: (52) Empty reply from server

```

Expected results

Obtain the right header information.

Actual results

curl: (52) Empty reply from server

This was identified as a bug and a fix was provided in community version 2.4.39.

Please refer to the following url: 

https://bz.apache.org/bugzilla/show_bug.cgi?id=63192