I use Joomla on several different sites, and it works great and have never had any problems install modules or components onto it.
How and where are you trying to upload from?
Incase you havent tried yet, at least what works for me, download the .zip or .gz file to your Linux Desktop, then in the Install Components page in your Joomla Admin area, there are 2 options of install. 1) is "Upload Package File" and 2) is "Install from directory", obviously install from directory and use the path to the appropriate file on your desktop. You shouldnt even need to unzip/gunzip it, as Joomla will handle this for you
Also under Install from directory, please be sure that yours looks like this:
And if not, then a simple chmod 700 -R
to your joomla dir will fix that.
Hope this helps.