[wp-hackers] preg_match_all() Crashes Server

Mike Walsh mpwalsh8 at gmail.com
Wed Mar 13 19:31:05 UTC 2013


Both my server and the other user's server are running PHP 5.2.17.


On Wed, Mar 13, 2013 at 12:01 PM, peter baylies <
pbaylies at semperfiwebdesign.com> wrote:

> What PHP version is being used? It could be a bug...
> https://bugs.php.net/bug.php?id=28513
>
> Cheers,
>
>  -- Peter
>
> On Wed, Mar 13, 2013 at 11:01 AM, Mike Walsh <mpwalsh8 at gmail.com> wrote:
>
> > A user of my WordPress Google Form plugin has run into an odd problem
> where
> > visiting the Plugin Settings page results in a server crash.  I can't
> > replicate it but he provided me access to a test site where I was able to
> > determine that a call to preg_match_all() is what is crashing the server.
> >
> > I am not sure how to resolve this.  What I am doing is using
> > wp_remote_get() to scrape the FAQ and Usage content for my plugin from
> the
> > WordPress Plugin Repository (the content from the ReadMe file), extract
> > what I want, and put the content on a tab on my Settings Page.  Doing
> this
> > allowed me an easy way to add Help to my plugin within the Settings Page.
> >
> > I've put a fragment of the code here in PastBin:
> > http://pastebin.com/RrYxAdiU
> >
> > This is the regular expression which fails:
> >
> >         $pattern_short =
> >
> >
> '{<div\s+[^>]*?class="block-content"[^>]*>((?:(?:(?!<div[^>]*>|</div>).)++|<div[^>]*>(?1)</div>)*)</div>}si';
> >         $matchcount = preg_match_all($pattern_short, $data, $matches);
> >
> > After Googling a bit I thought the user might have an incorrect setting
> for
> > pcre.backtrace_limit but his value (100000) is the same as what I have on
> > my server.
> >
> > I am not sure what else to check at this point.
> >
> > --
> > Mike Walsh - mpwalsh8 at gmail.com
> > _______________________________________________
> > wp-hackers mailing list
> > wp-hackers at lists.automattic.com
> > http://lists.automattic.com/mailman/listinfo/wp-hackers
> >
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-- 
Mike Walsh - mpwalsh8 at gmail.com


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