What I've been wondering is, do people actually set up fine-grained firewall rules for ICMP traffic or not? If they do, what are the rules specifically? Genera

What I've been wondering is, do people actually set up fine-grained firewall rules for ICMP traffic or not? If they do, what are the rules specifically? Generally speaking, just allowing all of ICMP does not seem like a major issue. Denial of service via ICMP is possible but then again, that's always possible no matter what.