As preparation step for configuring test/scratch base fs
for overlay tests:
- Rename OVERLAY_LOWER/UPPER/WORK_DIR => OVL_LOWER/UPPER/WORK
because we want to use OVL_ prefix for all base fs vars
- Prepend "ovl-" prefix to lower/upper/work path values to
isolate the overlay test dirs when running on a base fs
that is also used to run non overlay tests
- Make those vars values non-configurable, because lower/upper/work
directory names are an internal test detail which should
not concern the user and because we wish to simplify
and document the overlay tests setup
- Add helper _filter_ovl_dirs and use it to filter output
of test overlay/023 which matches the constant string "work"
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>
Via unshare, copy up dir from lower dir then remove
them in another unshared namespace.
This would fail before v4.7 kernel with EPERM.
Kernel commit 3fe6e52f
ovl: override creds with the ones from the superblock mounter
fixed this issue, with this reproducer provided. Original
reproducer was written by commit author:
Antonio Murdaca <amurdaca@redhat.com>
Signed-off-by: Xiong Zhou <xzhou@redhat.com>
Reviewed-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>