Critical bug: Attachments were accidentally deleted

• Gitea version (or commit ref): 1.4.2 / af57d6a
• Git version: N/A
• Operating system: N/A
• Database:
  • PostgreSQL
  • MySQL
  • MSSQL
  • SQLite
• Can you reproduce the bug at https://try.gitea.io:
  • Yes (provide example URL)
  • No
  • Not relevant
• Log gist: N/A

Description

Steps to Reproduce

1. Create repository: "Repo1"
2. Create an issue and upload some attachments
   (https://try.gitea.io allow image/jpeg|image/png|application/zip|application/gzip)
3. Create repository: "Repo2"
4. Create an issue in "Repo2"
5. Delete "Repo2"
6. Any attachments uploaded to issue/release/PR were accidentally deleted from database and disk, no matter which user uploaded the files (Attachments uploaded to comment are not affected)

I think it's caused by #1092

gitea/models/repo.go

Line 1845 in af57d6a

if _, err = sess.In("issue_id", issueIDs).Delete(&Comment{}); err != nil {

c.ID == 0 here

gitea/models/issue_comment.go

Lines 149 to 155 in af57d6a

	func (c *Comment) AfterDelete() {
	_, err := DeleteAttachmentsByComment(c.ID, true)
	if err != nil {
	log.Info("Could not delete files for comment %d on issue #%d: %s", c.ID, c.IssueID, err)
	}
	}

Screenshots

N/A