dom: clear the xpath callback registrations before freeing them - #306
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dom: clear the xpath callback registrations before freeing them#306iliaal wants to merge 1 commit into
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php_dom_xpath_callbacks_dtor() freed php_ns and each namespaces entry while leaving registry->php_ns and registry->namespaces pointing at them, and it then destroyed node_list, which runs node destructors. A destructor calling gc_collect_cycles() therefore reached php_dom_xpath_callback_ns_get_gc() through the still-set fields and iterated freed memory. Reachable from userland by calling DOMXPath::__construct() a second time on an object that has php:function registrations and a populated node list. Closes phpGH-23621
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Promoted upstream as php#23621. |
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php_dom_xpath_callbacks_dtor()freedphp_nsand eachnamespacesentry but leftregistry->php_nsandregistry->namespacespointing at the freed memory, and it then destroyednode_list, which runs node destructors. A destructor that callsgc_collect_cycles()reachesphp_dom_xpath_callback_ns_get_gc()through those still-set fields and iterates freed memory.Reachable from userland by calling
DOMXPath::__construct()a second time on an object that already hasphp:functionregistrations and a populated node list, which is the path atext/dom/xpath.cthat tears the registry down on a live object.