Public bug reported: Rsync has an astonishing and dangerous bug:
The dry run feature (-n / --dry-run) fails to report file deletions when --remove-source-files is used. This is quite serious. People use --dry- run to see if an outcome will work as expected before a live run. When the simulated run shows *less* destruction than the live run, the consequences can be serious because rsync may unexpectedly destroy the only copy of a file. Users rely on --dry-run. Although users probably expect --dry-run to have limitations, we don't expect destructive operations to be under reported. If it were reversed, such that the live run were less destructive than the dry run, this wouldn't be as serious. Reproducer: $ mkdir -p /tmp/src /tmp/dest $ printf '%s\n' 'yada yada' > /tmp/src/foo.txt $ printf '%s\n' 'yada yada' > /tmp/src/bar.txt $ cp /tmp/src/foo.txt /tmp/dest $ ls /tmp/src/ /tmp/dest/ /tmp/dest/: foo.txt /tmp/src/: bar.txt foo.txt $ rsync -na --info=remove1 --remove-source-files --existing src/* dest/ (no output) $ rsync -a --info=remove1 --remove-source-files --existing src/* dest/ sender removed foo.txt $ ls /tmp/src/ /tmp/dest/ /tmp/dest/: foo.txt /tmp/src/: bar.txt Note this bug is similar but differs in a few ways: https://bugzilla.samba.org/show_bug.cgi?id=3844 I've marked this as a security vulnerability because it causes unexpected data loss due to --dry-run creating a false expectation. ** Affects: rsync (Ubuntu) Importance: Undecided Status: New ** Information type changed from Private Security to Public -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to rsync in Ubuntu. https://bugs.launchpad.net/bugs/1925381 Title: rsync conceals file deletions from reporting when --dry-run --remove- source-files are used together Status in rsync package in Ubuntu: New Bug description: Rsync has an astonishing and dangerous bug: The dry run feature (-n / --dry-run) fails to report file deletions when --remove-source-files is used. This is quite serious. People use --dry-run to see if an outcome will work as expected before a live run. When the simulated run shows *less* destruction than the live run, the consequences can be serious because rsync may unexpectedly destroy the only copy of a file. Users rely on --dry-run. Although users probably expect --dry-run to have limitations, we don't expect destructive operations to be under reported. If it were reversed, such that the live run were less destructive than the dry run, this wouldn't be as serious. Reproducer: $ mkdir -p /tmp/src /tmp/dest $ printf '%s\n' 'yada yada' > /tmp/src/foo.txt $ printf '%s\n' 'yada yada' > /tmp/src/bar.txt $ cp /tmp/src/foo.txt /tmp/dest $ ls /tmp/src/ /tmp/dest/ /tmp/dest/: foo.txt /tmp/src/: bar.txt foo.txt $ rsync -na --info=remove1 --remove-source-files --existing src/* dest/ (no output) $ rsync -a --info=remove1 --remove-source-files --existing src/* dest/ sender removed foo.txt $ ls /tmp/src/ /tmp/dest/ /tmp/dest/: foo.txt /tmp/src/: bar.txt Note this bug is similar but differs in a few ways: https://bugzilla.samba.org/show_bug.cgi?id=3844 I've marked this as a security vulnerability because it causes unexpected data loss due to --dry-run creating a false expectation. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/rsync/+bug/1925381/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
