It escaped my attention at the time, but Ubuntu 18.04 released with both a version of duplicity that shows the new incremental-backups-also-have- this-issue behavior (see my comment 22) and a release of deja-dup that wasn't yet fixed to avoid it.
Which means that deja-dup in Ubuntu 18.04 is still affected by this bug (for incremental backups). These two commits landed in deja-dup 39.1 and should work around it, if someone wanted to patch deja-dup in 18.04 (I've opened a target for bionic for this bug): https://gitlab.gnome.org/World/deja-dup/-/commit/4f325940dae7fc259b4be70fccec40c94617f4d4 https://gitlab.gnome.org/World/deja-dup/-/commit/135f4c83774b6dafe194236f99f1405f45032498 For users, you can also install the snap version of deja-dup to avoid this as well. ** Also affects: duplicity (Ubuntu Bionic) Importance: Undecided Status: New ** Also affects: deja-dup (Ubuntu Bionic) Importance: Undecided Status: New -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to duplicity in Ubuntu. https://bugs.launchpad.net/bugs/918489 Title: duplicity allows a new, different passphrase if an archive cache exists Status in Déjà Dup: Fix Released Status in Duplicity: Fix Released Status in deja-dup package in Ubuntu: Fix Released Status in duplicity package in Ubuntu: Triaged Status in deja-dup source package in Trusty: Fix Released Status in duplicity source package in Trusty: Confirmed Status in deja-dup source package in Xenial: Fix Released Status in duplicity source package in Xenial: Confirmed Status in deja-dup source package in Yakkety: Fix Released Status in duplicity source package in Yakkety: Confirmed Status in deja-dup source package in Bionic: New Status in duplicity source package in Bionic: New Bug description: when doing a backup for the first time, dejadup verifies your passphrase by having you enter it twice. on future incremental backups it doesn't need to do this because entering the wrong password will result in the backup failing. with the periodic 'full' backups that happen from time to time, however, any password will be accepted. this can lead to a situation where you accidentally type the wrong password once and are left in a situation where you don't know what you typed and have no way to get your files (or do another incremental backup on top of it). i think this is what happened to me recently. clearly, the fix is to explicitly verify the passphrase is correct when doing a new full backup. this may be a duplicity bug. === Ubuntu deja-dup SRU information === [impact] Users may unwittingly re-set their backup password and not be able to restore their data. [test case] - $ deja-dup-preferences # set up a dummy backup - $ deja-dup --backup # complete first encrypted full backup - $ rename 's/\.2016/\.2000/' /path/to/test/backup/* - $ rename 's/\.2016/\.2000/' ~/.cache/deja-dup/*/* - $ deja-dup --backup # second backup, enter the wrong password - $ deja-dup --restore # try to restore with original password [regression potential] Should be limited? The fix is to delete the duplicity cache files, which ought to be safe to delete. It's possible if a full backup is being resumed, we might delete the current progress. That is a better bug to have than this bug, though. A more complicated patch would need to be investigated to prevent that. To manage notifications about this bug go to: https://bugs.launchpad.net/deja-dup/+bug/918489/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
