Is this a bug? (Tails 3.3)

Question

When I try to open/save a file in Tor Browser the 'Places' menu show the /usr/local/lib/tor-browser as a option.

At the same time it doesn't allow to acess the home folder or the desktop folder.

The Tor Browser in the home folder can be normally accessible. The fact of /usr/local/lib/tor-browser be accessible but not the home or desktop folders is OK or a bug?

Answer 1

This is intended, since this is the location that Tor Browser executes from and libraries and other files related to Tor Browser are stored it needs to be able to read this directory, this is explicitly defined in the AppArmor profile that's provided for Tor Browser in /etc/apparmor.d/torbrowser:

  /usr/local/lib/tor-browser/ r,
  /usr/local/lib/tor-browser/** r,
  /usr/local/lib/tor-browser/*.so{,.6} mr,
  /usr/local/lib/tor-browser/**/*.so mr,
  /usr/local/lib/tor-browser/browser/* r,
  /usr/local/lib/tor-browser/TorBrowser/Data/Browser/profiles.ini r,

This provides only read access, as such Tor Browser can read these files but cannot change them.

Similarly, other parts of the amnesia user's home folder are denied with explicit exceptions set for ~/Tor Browser, ~/Persistent/Tor Browser and the ammesia user's local Tor Browser profile:

  owner "@{HOME}/Tor Browser/" rw,
  owner "@{HOME}/Tor Browser/**" rwk,
  owner "@{HOME}/Persistent/Tor Browser/" rw,
  owner "@{HOME}/Persistent/Tor Browser/**" rwk,
  owner "/live/persistence/TailsData_unlocked/Persistent/Tor Browser/" rw,
  owner "/live/persistence/TailsData_unlocked/Persistent/Tor Browser/**" rwk,
  owner @{HOME}/.mozilla/firefox/bookmarks/** rwk,
  owner /live/persistence/TailsData_unlocked/bookmarks/** rwk,
  owner @{HOME}/.tor-browser/profile.default/ r,
  owner @{HOME}/.tor-browser/profile.default/** rwk,