Public bug reported:
Another affected host (Kubuntu 26.04.1 "resolute", amd64, kernel
7.0.0-31-generic,
bubblewrap 0.11.1-1ubuntu0.2): Chrome, LibreOffice, Opera and Zen all broke
immediately
after the 14:10 upgrade. Two additions to this report:
1) The Discord error is not limited to launching Discord itself.
md.obsidian.Obsidian
fails with the exact same error even though Discord is not involved at runtime
— its
manifest contains `filesystems=...;xdg-run/app/com.discordapp.Discord:create;`
(Rich
Presence):
bwrap: Can't bind mount /oldroot/run/user/1000/app/com.discordapp.Discord on
/newroot/run/user/flatpak/app/com.discordapp.Discord: Unable to mount
source on
destination: No such file or directory
`flatpak info -m md.obsidian.Obsidian` shows
sockets=fallback-x11;pulseaudio;ssh-auth;
wayland; (no cups) — the failing part is the xdg-run/app filesystem.
Workaround for this variant (verified, app starts normally):
flatpak override --user --nofilesystem=xdg-run/app/com.discordapp.Discord
md.obsidian.Obsidian
(flatpak prints "Filesystem suffix \"create\" is not applicable for
--nofilesystem"
but stores filesystems=!xdg-run/app/com.discordapp.Discord; and it works.)
Among the 26 flatpaks on this host, only Obsidian uses an
xdg-run/app/<other-app>
filesystem, so this variant has a long tail that will keep hitting
unrelated apps.
2) Minimal repro without flatpak + control matrix, showing this is a bind-path
resolution
bug, not socket/CUPS-specific (a plain regular file fails the same way):
BASE='--unshare-user --disable-userns --proc /proc --dev /dev --dir /tmp \
--tmpfs /run --symlink ../run /var/run --ro-bind /usr /usr \
--symlink usr/lib64 /lib64 --symlink usr/lib /lib'
# Fails with ELOOP (exit 1):
bwrap $BASE --ro-bind /var/run/cups/cups.sock /var/run/cups/cups.sock
/usr/bin/true
bwrap $BASE --ro-bind /etc/hostname /var/run/testfile /usr/bin/true
# The exact same binds succeed (exit 0) when the destination avoids
/var/run:
bwrap $BASE --ro-bind /var/run/cups/cups.sock /run/cups/cups.sock
/usr/bin/true
bwrap $BASE --ro-bind /etc/hostname /run/testfile /usr/bin/true
Summary of the pattern: any --ro-bind/--bind whose DESTINATION is under
/var/run/...
after `--symlink ../run /var/run` fails with ELOOP; and bind paths under
/run/user/1000/app/... get mis-resolved one level up (/run/user/flatpak/...)
when the
per-app private xdg-run bind (`--bind /run/user/1000/.flatpak/<app>/xdg-run
/run/user/1000`) is in place. It looks like bind source/destination paths are
being
resolved against symlinks bwrap itself created/mounted earlier in the same
invocation.
ProblemType: Bug
DistroRelease: Ubuntu 26.04
Package: bubblewrap 0.11.1-1ubuntu0.2
ProcVersionSignature: Ubuntu 7.0.0-31.31-generic 7.0.14
Uname: Linux 7.0.0-31-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia zfs
ApportVersion: 2.34.1-0ubuntu0.1
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: KDE
Date: Thu Sep 17 16:25:28 2026
InstallationDate: Installed on 2026-05-07 (133 days ago)
InstallationMedia: Kubuntu 26.04 "Resolute Raccoon" - Release amd64 (20260423)
SourcePackage: bubblewrap
UpgradeStatus: No upgrade log present (probably fresh install)
** Affects: bubblewrap (Ubuntu)
Importance: Undecided
Status: New
** Tags: amd64 apport-bug resolute wayland-session
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2167650
Title:
flatpak info -m md.obsidian.Obsidian shows
sockets=fallback-x11;pulseaudio;ssh-auth; wayland; (no cups) — the
failing part is the xdg-run/app filesystem.
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/bubblewrap/+bug/2167650/+subscriptions
--
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
