The cases where xml_parse() returns false is broader than the strict definition of invalid XML. For example, libxml loads the values of attributes into dynamically allocated memory. With ulimit/cgroup limiting memory usage, the malloc() can return NULL, which leads to xml_parse() returning 0 and giving a PHP warning like:

Warning: xml_parse(): Memory allocation failed : growing buffer in /srv/mw/core/includes/libs/XmlTypeCheck.php on line 124

Created attachment 14116
Return error on invalid XML

attachment bug58553.patch ignored as obsolete

Hmm.. didn't see your comment until I posted that. Perhaps the error should be "Couldn't parse the XML"?

Created attachment 14124
Return error if XML can't be parsed for SVGs

Added the translations to this version. Updated the message per Tim's comment.

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Looks good.

Created attachment 14143
Patch rebased on the patch for bug 57550

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This was assigned CVE-2013-6453

Created attachment 14267
Return error if XML can't be parsed for SVGs (1.19 branch)

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Created attachment 14268
Return error if XML can't be parsed for SVGs (1.21 branch)

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Created attachment 14269
Return error if XML can't be parsed for SVGs (1.22 branch)

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