This fixes a regression in mediation of getattr when old policy built
under an older ABI is loaded and mapped to internal permissions.
The regression does not occur for all getattr permission requests,
only appearing if state zero is the final state in the permission
lookup. This is because despite the first state (index 0) being
guaranteed to not have permissions in both newer and older permission
formats, it may have to carry permissions that were not mediated as
part of an older policy. These backward compat permissions are
mapped here to avoid special casing the mediation code paths.
Since the mapping code already takes into account backwards compat
permission from older formats it can be applied to state 0 to fix
the regression.
Fixes: 408d53e923 ("apparmor: compute file permissions on profile load")
Reported-by: Philip Meulengracht <the_meulengracht@hotmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
When compute_fperms was moved to policy_compat and made static it
was renamed from aa_compute_fperms to just compute_fperms to help
indicate it is only available statically. Unfortunately the doc
comment did not also get updated to reflect the change.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
The details of mapping old policy into newer policy formats clutters
up the unpack code and makes it possible to accidentally use old
mappings in code, so isolate the mapping code into its own file.
This will become more important when the dfa remapping code lands,
as it will greatly expand the compat code base.
Signed-off-by: John Johansen <john.johansen@canonical.com>
