Deleting a page that is part of a partial block causes problems
Closed, ResolvedPublic1 Estimated Story Points
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Authored By

	Jni
	Jan 26 2019, 2:48 PM

Description

In test.wikipedia.org Mediawiki 1.33.0-wmf.14 (rMWa6319bcf893c):

1: Partial block User:Apples from a page (e.g. Astronaut)
2: delete Astronaut
3: Now User:Apples cannot edit at all, anywhere!

User Jni-test789 sees error messages:

Screen Shot 2019-01-30 at 3.30.09 PM.png (928×1 px, 183 KB)

Screen Shot 2019-01-30 at 3.24.07 PM.png (928×1 px, 83 KB)

PHP fatal error: Argument 1 passed to Title::equals() must be an instance of Title, null given

Also the page name vanishes from block list:

https://test.wikipedia.org/wiki/Special:BlockList?wpTarget=Jni-test789&limit=50&wpFormIdentifier=blocklist

Even worse, now I the blocking admin (in separate browser application) get the same error when trying to navigate to the deleted page:

https://test.wikipedia.org/w/index.php?title=User:Jni-test789/sandbox&action=edit&redlink=1

Or when I try to edit the block, I recieve:

Screen Shot 2019-01-30 at 3.25.01 PM.png (928×1 px, 275 KB)

Restoring the page restores blocked users editing of other pages and my access to it.

Details

	Subject	Repo	Branch	Lines +/-
	Prevent fatal PHP errors when PageRestriction::getTitle() returns null.	mediawiki/core	master	+42 -11

Customize query in gerrit

Related Objects

Mentioned In: T271253: Partial block from deleted page remains visibly, but not technically, in place
Mentioned Here: rMW9eafd89011b9: Merge "Prevent fatal PHP errors when PageRestriction::getTitle() returns null."
rMW4091905d5b01: Merge "resourceloader: Ignore warnings in JSMinPlus parser"
T214716: Block is incorrectly applied if partial block feature is enabled then disabled
rMWa6319bcf893c: Update git submodules

Event Timeline

Jni created this task.Jan 26 2019, 2:48 PM

Restricted Application added a subscriber: Aklapper. · View Herald TranscriptJan 26 2019, 2:48 PM

Restricted Application added a subscriber: MGChecker. · View Herald TranscriptJan 26 2019, 3:03 PM

Aklapper added a project: MediaWiki-Page-deletion.Jan 26 2019, 4:10 PM

Yep, just reproduced. This happens when the page deleted is the only page of a partial block, or one of many.

• TBolliger renamed this task from Deleting a page that is part of a partial block prevents blocked user editing any redlinked pages to Deleting a page that is part of a partial block causes problems.Jan 30 2019, 11:31 PM

• TBolliger updated the task description. (Show Details)

• TBolliger added a project: MediaWiki-User-management.

Change 487310 had a related patch set uploaded (by Dbarratt; owner: Dbarratt):
[mediawiki/core@master] PageRestriction::getTitle() can return null which throws a fatal PHP error.

https://gerrit.wikimedia.org/r/487310

gerritbot added a project: Patch-For-Review.Jan 30 2019, 11:46 PM

dbarratt claimed this task.Jan 30 2019, 11:47 PM

dbarratt edited projects, added Anti-Harassment (Bet — ב); removed Anti-Harassment.

dbarratt set the point value for this task to 1.

dbarratt moved this task from Ready to Review on the Anti-Harassment (Bet — ב) board.

• TBolliger edited projects, added Anti-Harassment (Gimel — ג); removed Anti-Harassment (Bet — ב).Feb 5 2019, 7:47 PM

• TBolliger moved this task from Ready to Review on the Anti-Harassment (Gimel — ג) board.

Tchanders moved this task from Review to QA/Testing on the Anti-Harassment (Gimel — ג) board.Feb 12 2019, 4:15 PM

Change 487310 merged by jenkins-bot:
[mediawiki/core@master] Prevent fatal PHP errors when PageRestriction::getTitle() returns null.

https://gerrit.wikimedia.org/r/487310

ReleaseTaggerBot added a project: MW-1.33-notes (1.33.0-wmf.17; 2019-02-12).Feb 12 2019, 5:00 PM

Behaviour in Description no longer occurs. Deleting a blocked page does not prevent the user editing other pages, anyone visiting the deleted page or the admin from editing or deleting the block.

The deleted page does not appear in the BlockList, but I think this is reasonable. The row blocking the user from the (now deleted) page remains in ipblocks_restrictions (unless you edit the block, in which case it is deleted). If you restore the deleted page then the block for that page comes into force again.

I have tried this for pages in namespaces main, User, User_talk and File. It does not seem likely that this would make a difference as page blocks appear to work the same for all namespaces.

Tried the same with an IP that was autoblocked. Same deal as above.

Testing on https://en.wikipedia.beta.wmflabs.org (version 1.33.0-alpha (4091905) 05:36, 13 February 2019) and my local wiki (1.33.0-alpha (9eafd89) 16:27, 12 February 2019).

@dbarratt I think I am ready to call this done, but please review. My understanding is that the bug occurred when a row in the table "ipblocks_restrictions" referred to a row in the table "page" that no longer existed. Deleting the page removed the row in the table, and so caused the problems we were seeing. I cannot see other variables or conditions that are relevant, so I cannot see anything else to test.

dbarratt closed this task as Resolved.Feb 13 2019, 3:55 PM

dbarratt moved this task from QA/Testing to Done on the Anti-Harassment (Gimel — ג) board.

ToBeFree mentioned this in T271253: Partial block from deleted page remains visibly, but not technically, in place.Jan 5 2021, 8:38 PM

Maintenance_bot removed a project: Patch-For-Review.Jan 5 2021, 9:11 PM

dbarratt removed dbarratt as the assignee of this task.Jan 5 2021, 9:12 PM

dbarratt subscribed.

dbarratt unsubscribed.

	F28081163: Screen Shot 2019-01-30 at 3.25.01 PM.png
	Jan 30 2019, 11:31 PM

	F28081156: Screen Shot 2019-01-30 at 3.30.09 PM.png
	Jan 30 2019, 11:31 PM

	F28081154: Screen Shot 2019-01-30 at 3.24.07 PM.png
	Jan 30 2019, 11:31 PM

Deleting a page that is part of a partial block causes problemsClosed, ResolvedPublic1 Estimated Story PointsActions

Description

Details

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Event Timeline

Deleting a page that is part of a partial block causes problems
Closed, ResolvedPublic1 Estimated Story Points
Actions