Steps to reproduce
- Add the config:
- $wgAutoCreateTempUser['enabled'] = true;
- wfLoadExtension( 'SpamBlacklist' );
- $wgLogSpamBlacklistHits = true;
- As an admin, add the line example.org to MediaWiki:Spam-blacklist
- Log out and try to add http://example.org/ to an article
This encounters the CannotCreateActorException:
[f6829f9e7a9d7a175bde6390] /mediawiki/core/index.php?title=Flour&action=submit CannotCreateActorException: Cannot create an actor for a usable name that is not an existing user: user_name="*184"
Backtrace:
from /var/www/html/mediawiki/core/includes/user/ActorStore.php(632)
#0 /var/www/html/mediawiki/core/includes/user/ActorStore.php(416): MediaWiki\User\ActorStore->validateActorForInsertion()
#1 /var/www/html/mediawiki/core/includes/logging/ManualLogEntry.php(299): MediaWiki\User\ActorStore->acquireActorId()
#2 /var/www/html/mediawiki/extensions/SpamBlacklist/includes/SpamBlacklist.php(252): ManualLogEntry->insert()
#3 /var/www/html/mediawiki/extensions/SpamBlacklist/includes/SpamBlacklist.php(152): MediaWiki\Extension\SpamBlacklist\SpamBlacklist->logFilterHit()
#4 /var/www/html/mediawiki/extensions/SpamBlacklist/includes/Hooks.php(135): MediaWiki\Extension\SpamBlacklist\SpamBlacklist->filter()
#5 /var/www/html/mediawiki/core/includes/HookContainer/HookContainer.php(159): MediaWiki\Extension\SpamBlacklist\Hooks->onEditFilterMergedContent()
#6 /var/www/html/mediawiki/core/includes/HookContainer/HookRunner.php(1476): MediaWiki\HookContainer\HookContainer->run()
#7 /var/www/html/mediawiki/core/includes/editpage/Constraint/EditFilterMergedContentHookConstraint.php(106): MediaWiki\HookContainer\HookRunner->onEditFilterMergedContent()
#8 /var/www/html/mediawiki/core/includes/editpage/Constraint/EditConstraintRunner.php(88): MediaWiki\EditPage\Constraint\EditFilterMergedContentHookConstraint->checkConstraint()
#9 /var/www/html/mediawiki/core/includes/editpage/EditPage.php(2401): MediaWiki\EditPage\Constraint\EditConstraintRunner->checkConstraints()
#10 /var/www/html/mediawiki/core/includes/editpage/EditPage.php(1785): MediaWiki\EditPage\EditPage->internalAttemptSave()
#11 /var/www/html/mediawiki/core/includes/editpage/EditPage.php(715): MediaWiki\EditPage\EditPage->attemptSave()
#12 /var/www/html/mediawiki/core/includes/actions/EditAction.php(66): MediaWiki\EditPage\EditPage->edit()
#13 /var/www/html/mediawiki/core/includes/actions/SubmitAction.php(38): EditAction->show()
#14 /var/www/html/mediawiki/core/includes/actions/ActionEntryPoint.php(733): SubmitAction->show()
#15 /var/www/html/mediawiki/core/includes/actions/ActionEntryPoint.php(510): MediaWiki\Actions\ActionEntryPoint->performAction()
#16 /var/www/html/mediawiki/core/includes/actions/ActionEntryPoint.php(145): MediaWiki\Actions\ActionEntryPoint->performRequest()
#17 /var/www/html/mediawiki/core/includes/MediaWikiEntryPoint.php(199): MediaWiki\Actions\ActionEntryPoint->execute()
#18 /var/www/html/mediawiki/core/index.php(58): MediaWiki\MediaWikiEntryPoint->run()
#19 {main}Problem
This is because an unsaved temporary user has been passed to ManualLogEntry::insert, which tries to find the actor ID.
This is similar to T358632 but likely more general, since it is coming from ManualLogEntry. The unsaved temporary user is created by EditPage and checked against several constraints. Any of these that insert a log could have the same problem.
Solution
Logs in general
- If we log the IP user instead, that would leak the IP address. Restricting the visibility of the logs to users with the IP reveal right would be difficult because it could affect lots of log types. We'd also need to purge those IPs from core.
- If we make the temp account, that would give access to the IP reveal infrastructure for free, if the action also makes it into the CheckUser tables. Though if it doesn't, we'd lose the IP address information.
SpamBlacklist in particular
SpamBlacklist::logFilterHit logs to CheckUser instead if a log is considered restricted, so we could either:
- Log the IP actor but only log in CheckUser, if it's OK for only checkusers to see the log; or
- Make the temp account (with the rate limiting caveats mentioned in T334623#9588779), in which case SpamBlacklist already logs to CheckUser via recent changes.