tree ded15d15eab41c31b428e8a19fee9111de0ca4d5
parent f168f1098dd9038daaf9f7be5f81cdea4985886a
author Amir Goldstein <amir73il@gmail.com> 1515616178 +0200
committer Miklos Szeredi <mszeredi@redhat.com> 1516789551 +0100

ovl: verify stored origin fh matches lower dir

When the NFS export feature is enabled, overlayfs implicitly enables the
feature "verify_lower". When the "verify_lower" feature is enabled, a
directory inode found in lower layer by name or by redirect_dir is
verified against the file handle of the copy up origin that is stored in
the upper layer.

This introduces a change of behavior for the case of lower layer
modification while overlay is offline. A lower directory created or
moved offline under an exisitng upper directory, will not be merged with
that upper directory.

The NFS export feature should not be used after copying layers, because
the new lower directory inodes would fail verification and won't be
merged with upper directories.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>