rules: drop rules with noalert not fully dropping
A simple drop rules like
drop tcp any any -> any any (noalert; sid:1; rev:1;) fails to drop packets beyond the first in each direction of the flow.
The cause is that the rule is just evaluated once per flow direction, by the "IP-only" detection path. In this case the 'noalert' presence causes the drop not to be applied to the flow.