Validate that the permission maps in the scope index refer to a valid
class datum. Otherwise since commit 52e5c306 ("libsepol: move unchanged
data out of loop") this can lead to a NULL dereference in the class
existence check during linking.
Reported-by: oss-fuzz (issue 69655)
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Acked-by: James Carter <jwcart2@gmail.com>
589e2dba72