Author: md_yosri
Description:
Screen print
Error message when access History >50:-
[324b0ea2] 2012-07-21 23:06:02: Fatal exception of type MWException
Problem on:-
Android, Windows
Browser:-
Dolfin, Chrome, IE6
Version: unspecified
Severity: major
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=41258
https://bugzilla.wikimedia.org/show_bug.cgi?id=41400
Attached:
Trying with the api, i think its probably this edit (might have got the offset wrong, so might be wrong):
<rc type="edit" ns="14" title="Kategori:86 SM" rcid="2371588" pageid="278625" revid="2279068" old_revid="2112444" user="Xqbot" userid="40750" bot="" minor="" oldlen="955" newlen="965" timestamp="2012-07-22T22:44:56Z" comment="r2.7.3) (Bot: Menukar [[fr:Catégorie:-86]] kepada [[fr:Catégorie:86 av. J.-C.]]" parsedcomment="r2.7.3) (Bot: Menukar <a href="//fr.wikipedia.org/wiki/Cat%C3%A9gorie:-86" class="extiw" title="fr:Catégorie:-86">fr:Catégorie:-86</a> kepada <a href="//fr.wikipedia.org/wiki/Cat%C3%A9gorie:86_av._J.-C." class="extiw" title="fr:Catégorie:86 av. J.-C.">fr:Catégorie:86 av. J.-C.</a>"> <tags /> </rc>
Nothing seems especially out of the ordinary from the api output
(If i was on my normal computer, I'd just look at the toolserver which would probably yield better info...)
I dug up the error plus backtrace in the logs, see below. The bad change seems to be rcid 2369742 (also dumped below), but I don't understand why. The backtrace implies something is wrong with the $this->params member of the Message object, but since it's just doing wfMessage('parentheses')->rawParams($formatted)->escaped(); where $formatted is the result of Linker::formatComment(), I don't see how it would get messed up.
CC Niklas because the exception occurs deep in the bowels of Message.php
<rc type="new" ns="10" title="Templat:IPAc-cmn" rcid="2369742" pageid="341526" revid="2277275" old_revid="0" timestamp="2012-07-21T14:42:08Z" />
mysql> select * from recentchanges where rc_id=2369742 \G
rc_moved_to_title:
rc_patrolled: 0
rc_ip: CENSORED
rc_old_len: 0
rc_new_len: 5510
rc_deleted: 0
rc_logid: 0
rc_log_type: NULL
rc_log_action:
rc_params:1 row in set (0.00 sec)
2012-07-23 22:36:31 srv234 mswiki: [7ce45821] /w/index.php?title=Khas:Perubahan_terkini&limit=686 Exception from line 571 of /usr/local/apache/common-local/php-1.20wmf7/includes/Message.php: Invalid message parameter
#0 /usr/local/apache/common-local/php-1.20wmf7/includes/Message.php(546): Message->extractParam(Array)
#1 /usr/local/apache/common-local/php-1.20wmf7/includes/Message.php(414): Message->replaceParameters('($1)', 'before')
#2 /usr/local/apache/common-local/php-1.20wmf7/includes/Message.php(491): Message->toString()
#3 /usr/local/apache/common-local/php-1.20wmf7/includes/Linker.php(1456): Message->escaped()
#4 /usr/local/apache/common-local/php-1.20wmf7/includes/ChangesList.php(435): Linker::commentBlock('Mencipta laman ...', Object(Title))
#5 /usr/local/apache/common-local/php-1.20wmf7/includes/ChangesList.php(640): ChangesList->insertComment(Object(RecentChange))
#6 /usr/local/apache/common-local/php-1.20wmf7/includes/specials/SpecialRecentchanges.php(527): OldChangesList->recentChangesLine(Object(RecentChange), false, 687)
#7 /usr/local/apache/common-local/php-1.20wmf7/includes/specials/SpecialRecentchanges.php(179): SpecialRecentChanges->webOutput(Object(ResultWrapper), Object(FormOptions))
#8 /usr/local/apache/common-local/php-1.20wmf7/includes/SpecialPage.php(611): SpecialRecentChanges->execute(NULL)
#9 /usr/local/apache/common-local/php-1.20wmf7/includes/SpecialPageFactory.php(493): SpecialPage->run(NULL)
#10 /usr/local/apache/common-local/php-1.20wmf7/includes/Wiki.php(263): SpecialPageFactory::executePath(Object(Title), Object(RequestContext))
#11 /usr/local/apache/common-local/php-1.20wmf7/includes/Wiki.php(601): MediaWiki->performRequest()
#12 /usr/local/apache/common-local/php-1.20wmf7/includes/Wiki.php(511): MediaWiki->main()
#13 /usr/local/apache/common-local/php-1.20wmf7/index.php(58): MediaWiki->run()
#14 /usr/local/apache/common-local/live-1.5/index.php(3): require('/usr/local/apac...')
#15 {main}
Not just RC: http://ms.wikipedia.org/w/index.php?title=Templat:IPAc-cmn&action=history gives [2d7f7a89] 2012-07-24 13:27:11: Fatal exception of type MWException
Ok, so this is weird. Possibly something messed with parser.
Go edit a page (doesn't matter what lang, testing on ms and en).
In the edit summary, type the following:
[[|||||||||]|-|-]A|-/
Hit preview. I get [41f2ddc1] 2012-07-24 13:42:10: Fatal exception of type MWException.
Note however, that everything is fine on special:expandtemplates. Exception only happens in edit summary. Also of interest is that http://ms.wikipedia.org/w/api.php?action=parse&summary=[[|||||||||]|-|-]A|-/&text=foo errors out too
The problem is in
Linker::formatLinksInComment:
$html = preg_replace_callback( '/\[\[:?(.*?)(\|(.*?))*\]\]([^[]*)/', array( 'Linker', 'formatLinksInCommentCallback' ), $comment );
preg_replace_callback encounters PREG_BACKTRACK_LIMIT_ERROR and returns null.
This is later on passed to wfMessage( ... )->rawParams( $html )->foo();
Message class checks
if ( is_array( $param ) && isset( $param['raw'] ) ) {But since it is array( 'raw' => null ); isset returns false and exception is raised.
Could @Niklas or @Roan submit a patch to fix this? Or are there non-trivial problems involved that may require broader refactoring?
Well for now we could just do if ( $html == null ) $html = $thingyBeforeWeTriedToParseIt In very very rare cases comments wouldn't have wikilinks formatted. Given the rarity of this happening I don't think its something that really matters.
Would the following regexp work?
\[\[:?([^\|\]\n]*?)(\|([^\|\]\n]*?))*\]\]([^[]*)
I've basically replaced every "." ("any character except for newline") with "[^\|\]\n]" ("any character except for |, ] or newline"). This prevents catastrophic backtracking[1].