linux-toradex.git/tools/testing/selftests/filesystems/mntns_unbindable, branch master Linux kernel for Apalis and Colibri modules selftests/filesystems: check that a copied mount namespace keeps unbindable 2026-09-25T15:20:32+00:00 Christian Brauner brauner@kernel.org 2026-09-23T12:27:54+00:00 0bab6b6d77607458a25710a42c42ae2343468d2c Make a tmpfs unbindable, copy the mount namespace and check from the copy that: - a bind of the mount fails with EINVAL - a recursive bind fails as well - open_tree(OPEN_TREE_CLONE) of it fails - mountinfo still shows it as unbindable - a copy of the copy refuses the bind too The first case runs in the original namespace so the fixture stays honest about what it set up. Link: https://patch.msgid.link/20260923-work-mount-fixes-v1-2-f424cf8d3242@kernel.org Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org> 
Make a tmpfs unbindable, copy the mount namespace and check from the
copy that:

- a bind of the mount fails with EINVAL

- a recursive bind fails as well

- open_tree(OPEN_TREE_CLONE) of it fails

- mountinfo still shows it as unbindable

- a copy of the copy refuses the bind too

The first case runs in the original namespace so the fixture stays
honest about what it set up.

Link: https://patch.msgid.link/20260923-work-mount-fixes-v1-2-f424cf8d3242@kernel.org
Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>