When upgraded from GA3 to 6.2.x, all attachments lost their default resource permissions

• Type: Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 6.2.X EE, 7.0.0 M3
• Fix Version/s: 6.2.1 CE GA2, 6.2.X EE, 7.0.0 M1
• Component/s: Core Infrastructure, Core Infrastructure > Upgrade Framework
• Labels:
  • liferay-fixpack-document-management-4-6210
• Branch Version/s:
  6.2.x
• Backported to Branch:
  Committed
• Story Points: 9
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/16198

When upgraded from GA3 to 6.2.x, all attachments lost their default resource permissions, so that attachments only can be viewed by owner or admin

Reproduce steps:

1. In GA3, Deploy a MB portlet on page "welcome" of guest site of Liferay.
2. Create a thread in MB portlet with attachments (named 'test.xml') with default permission (Guest can view).
3. Upgrade to 6.2.X
4. Deploy "Documents and Media" portlet on "welcome" page (need to deploy this portlet in order to access the attachments, refer to LPS-43640)
5. Access the attachments (test.xml) with an Guest.

Actual behavior:
Guest can't view, redirect to login page
Expect behavior:
Guest should be able to download the attachments.

The additional bug described by LPS-43640, please use the workaround of it to test this case.