[upload] "Generic Upload" directory issue

[dwolstroRH]

When a "Generic Upload" is encountered (meaning a
non-implemented distribution) and the upload directory
is not specified, fail with a helpful error message (the
upload would previously fail on permissions as it tries
to write to the root directory of sftp).

Related: RHEL-124680

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[packit-as-a-service]

Congratulations! One of the builds has completed. 🍾

You can install the built RPMs by following these steps:

• sudo yum install -y dnf-plugins-core on RHEL 8
• sudo dnf install -y dnf-plugins-core on Fedora
• dnf copr enable packit/sosreport-sos-4167
• And now you can install the packages.

Please note that the RPMs should be used only in a testing environment.

[TurboTurtle]

I don't know that we want to impose this as an always-fail situation.

In the case of a configured ChrootDirectory, the session will automatically switch to the user's home dir after applying the chroot. This means that it is entirely a valid configuration to not specify a directory and at the same time properly expect that the file being transferred end up in the ssh user's homedir instead of the rootdir of the sftp session.

This change would prevent an upload in such a configuration.