[PATCH v3 0/2] ovl: reject different lower idmaps on same fs

[Jérémy Jean]

Lower file handles identify a lower fs, but not the mount whose idmap
was used to decode them. Remember the first lower idmap seen for each
fs and fail the mount if another one appears.

Changes since v2:
- On a request by Christian Brauner, fail the mount instead of
  disabling lower file handle decoding.
- Check the idmap on the private lower clone.
- Replace the old regression tests with one mount setup test.

Jérémy Jean (2):
  ovl: reject different lower idmaps on the same fs
  selftests: overlayfs: reject different lower idmaps on same fs

 fs/overlayfs/ovl_entry.h                      |  2 +
 fs/overlayfs/super.c                          | 15 +++++++
 .../filesystems/overlayfs/idmapped_mounts.c   | 43 +++++++++++++++++++
 3 files changed, 60 insertions(+)
-- 
2.47.3