[wp-trac] [WordPress Trac] #22072: get_adjacent_post_rel_link() Can poison the post cache

[WordPress Trac]

#22072: get_adjacent_post_rel_link() Can poison the post cache
-----------------------------+--------------------------
 Reporter:  mdawaffe         |       Type:  defect (bug)
   Status:  new              |   Priority:  normal
Milestone:  Awaiting Review  |  Component:  Cache
  Version:  3.4              |   Severity:  normal
 Keywords:  has-patch        |
-----------------------------+--------------------------
 {{{get_adjacent_post_rel_link()}}} does:

 {{{
 if ( empty($post->post_title) )
     $post->post_title = $previous ? __('Previous Post') : __('Next Post');
 ...
 $title = apply_filters('the_title', $title, $post->ID);
 ...
 $link .= "' href='" . get_permalink($post) . "' />\n";
 }}}

 If the post cache gets cleared during {{{the_title}}} filter (or any of
 the several other hooks that are run but are not shown above), the
 modified {{{$post}}} object will be cached as modified during
 {{{get_permalink()}}}'s call to {{{get_post()}}}.

 This can only happen in WordPress <= 3.4.  In WordPress 3.5,
 {{{get_post()}}} has been rewritten in such a way this cache poisoning is
 no longer possible.  I think this fix was at least in part accidental,
 though, and probably not very robust.

 We shouldn't be setting {{{$post->post_title}}}.  We should set an
 intermediary variable instead.

 Patch and simple test script (not a unit test) attached.

-- 
Ticket URL: <http://core.trac.wordpress.org/ticket/22072>
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