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@@ -323,30 +323,6 @@ and::
The resulting access permissions should be the same. The difference is in
the time of copy (on-demand vs. up-front).
-### Non overlapping credentials
-
-As noted above, all access to the upper, lower and work directories is the
-recorded mounter's MAC and DAC credentials. The incoming accesses are
-checked against the caller's credentials.
-
-In the case where caller MAC or DAC credentials do not overlap the mounter, a
-use case available in older versions of the driver, the override_creds mount
-flag can be turned off. For when the use pattern has caller with legitimate
-credentials where the mounter does not. For example init may have been the
-mounter, but the caller would have execute or read MAC permissions where
-init would not. override_creds off means all access, incoming, upper, lower
-or working, will be tested against the caller.
-
-Several unintended side effects will occur though. The caller without certain
-key capabilities or lower privilege will not always be able to delete files or
-directories, create nodes, or search some restricted directories. The ability
-to search and read a directory entry is spotty as a result of the cache
-mechanism not re-testing the credentials because of the assumption, a
-privileged caller can fill cache, then a lower privilege can read the directory
-cache. The uneven security model where cache, upperdir and workdir are opened
-at privilege, but accessed without creating a form of privilege escalation,
-should only be used with strict understanding of the side effects and of the
-security policies.
Multiple lower layers
---------------------