Update CHANGELOG.md

CHANGELOG.md

@@ -12,7 +12,7 @@ IMPROVEMENTS:
 * agent: Added a new [`-config-format`](https://www.consul.io/docs/agent/options.html#_config_format) command line option which can be set to `hcl` or `json` to specify the format of configuration files. This is useful for cases where the file name cannot be controlled in order to provide the required extension. [[GH-3620](https://github.com/hashicorp/consul/issues/3620)]
 * agent: DNS recursors can now be specified as [go-sockaddr](https://godoc.org/github.com/hashicorp/go-sockaddr/template) templates. [[GH-2932](https://github.com/hashicorp/consul/issues/2932)]
 * agent: Serf snapshots no longer save network coordinate information. This enables recovery from errors upon agent restart. [[GH-489](https://github.com/hashicorp/serf/issues/489)]
-* agent: Added defensive code to prevent out of range ping times from infecting network coordinates. Updates to the coordinate system with round trip times higher than 10 seconds will log an error but will be ignored.
+* agent: Added defensive code to prevent out of range ping times from infecting network coordinates. Updates to the coordinate system with negative round trip times or round trip times higher than 10 seconds will log an error but will be ignored.
 * agent: The agent now warns when there are extra unparsed command line arguments and refuses to start. [[GH-3397](https://github.com/hashicorp/consul/issues/3397)]
 * agent: Updated go-sockaddr library to get CoreOS route detection fixes and the new `mask` functionality. [[GH-3633](https://github.com/hashicorp/consul/issues/3633)]
 * agent: Added a new [`enable_agent_tls_for_checks`](https://www.consul.io/docs/agent/options.html#enable_agent_tls_for_checks) configuration option that allows HTTP health checks for services requiring 2-way TLS to be checked using the agent's credentials. [[GH-3364](https://github.com/hashicorp/consul/issues/3364)]