Archive for October, 2010|Monthly archive page

AppArmor Fun with Firefox 4 Daily Builds

So, here’s a problem I’m sure millions of computer users have.

The latest nightly Firefox builds from the Ubuntu Mozilla Daily Build PPA suddenly stopped working for me; every time I started with my usual profile (in my Encrypted Private Directory), it complained that Firefox was already running (it wasn’t). Running with a profile in my unencrypted home directory, in the usual place, seemed to work. For a while I though the profile was hosed, or the new Firefox build had a problem with the encryption.

Turns out the AppArmor profile has been updated to confine write access to the only default Firefox profile location ( ~/.mozilla/firefox-4.0 in this case), and a few other select directories (like the default downloads directory). Since my profile was outside that directory, AppArmor was preventing Firefox from writing to the profile. Updating the AppArmor profile (by editing /etc/apparmor.d/local/usr.bin.firefox-4.0) with the following fixed the problem.

owner @{HOME}/Profiles/** rwk,

Just in case someone else out there runs into a similar problem. There might be somebody.