illumos gate

The default ACLs that derive from "trivial" ACLs are generally missing the SYNCHRONIZE bit (the "s" at the end of the ACE). For example, all ACEs in this ACL except the last one are missing the bit:

$ ls -lVd .
drwxr-xr-x   6 gwr      staff         19 Jan 12 22:33 .
                 owner@:--------------:-------:deny
                 owner@:rwxp---A-W-Co-:-------:allow
                 group@:-w-p----------:-------:deny
                 group@:r-x-----------:-------:allow
              everyone@:-w-p---A-W-Co-:-------:deny
              everyone@:r-x---a-R-c--s:-------:allow

This appears to be an oversight in the ACE masks derived from POSIX modes.
Any POSIX mode that allows modify should map to an ACE with SYNC set.