Problem

There is no option to white-list email addresses to prevent forwarded mail from being discarded as invalid under Service Management settings. There is a feature request raised in  JSDSERVER-1924 - Getting issue details... STATUS .

Diagnosis

Environment

• Any Jira Service Management with Incoming Mail Channel configured

Workaround

1. Navigate to Administration > Add-ons > Manage add-ons (on newer versions of Jira this would be Administration > Manage Apps > Manage Manage Apps )
2. Look for Jira Service Management and expand the section
   
3. Expand the XXX of XXX modules enabled
   
4. Disable these responsible modules of Service Management:
   1. SD Bulk filter(sdBulkFilter) for messages marked as spam
   2. SD sent from Jira filter(sdJiraFilter) for messages originating from a Jira instance
   3. SD auto reply filter(sdAutoReplyFilter) for messages with a different value than "no" set for the Auto-Submitted header

NOTE :

The provided workaround will apply to all emails processed by the filter, which can cause incorrectly created issues. Being able to white-list addresses should prevent this from happening.
To make sure that the right module has been disabled, run the query {{select * from pluginstate;}} and verify that {{com.atlassian.servicedesk:sdAutoReplyFilter}} is set to false.

Later versions of JSM may have had the module names changed to the following:
* Service project Bulk filter
* Service project auto reply filter
* Service project sent from Jira filter