Fix GH-21952: UAF in DOMNotation after DOCTYPE removal. #21955
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devnexen wants to merge 2 commits intophp:masterfrom
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Fix GH-21952: UAF in DOMNotation after DOCTYPE removal. #21955devnexen wants to merge 2 commits intophp:masterfrom
devnexen wants to merge 2 commits intophp:masterfrom
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Commit 9498bc3 wired Dom\Notation to its owning DocType by setting ret->parent = parent_dtd in create_notation. Because the orphan xmlEntity allocated for the wrapper is not in any tree, the parent pointer dangles once the DocType is removed and freed, triggering a use-after-free when parentNode is read (e.g. via var_dump on the surviving notation). Drop the parent assignment and align Dom\Notation::$parentNode with the W3C DOM Level 3 Core specification (always null) and ::$isConnected with it (always false). ownerDocument and baseURI keep working through doc.
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Commit 9498bc3 wired Dom\Notation to its owning DocType by setting
ret->parent = parent_dtd in create_notation. Because the orphan xmlEntity
allocated for the wrapper is not in any tree, the parent pointer dangles
once the DocType is removed and freed, triggering a use-after-free when
parentNode is read (e.g. via var_dump on the surviving notation).
Drop the parent assignment and align Dom\Notation::$parentNode with the
W3C DOM Level 3 Core specification (always null) and ::$isConnected with
it (always false). ownerDocument and baseURI keep working through doc.