Location of Manager Icon Uploads?

Stupid question, but when you go to upload an icon for a Module, where are those icons supposed to be uploaded? In /assets somewhere?

Methinks I’ve got permissions errors on my server, so the upload functionality isn’t working, but I’m also not seeing any other files in the mysterious "images" directory... I can’t seem to navigate above it from the upload window. I don’t know why I keep having permissions errors... sigh... I usually just end up uploading images via FTP instead of the browser.

Thanks.