I'm trying to define an audit rule with auditctl for clone() syscall, and I would expect that the a0 of clone() syscall (i.e. the clone_flags argument) without the CLONE_THREAD flag bit being set.

int clone(int (*fn)(void *), void *stack, int flags, void *arg, ...
                 /* pid_t *parent_tid, void *tls, pid_t *child_tid */ );

From man page of auditctl, -F option build a rule file: name, operation, value.
-F [n=v | n!=v | n<v | n>v | n<=v | n>=v | n&v | n&=v]

I can understand that, the n&v (Audit_bitmask) means any bit of a bitmast is set, and the n&=v (Audit_bittest) means all bits of a bitmask are set.

While my question is, how to build a rule which means "none of bit of a bitmask is set", i.e. ( ! n&=v ). If the current audit comparator dosen't support this, can we add the support in furture?

Thanks,
Richard