Merge branch 'PHP-8.1' into PHP-8.2

* PHP-8.1:
  Fix GH-11288 and GH-11289 and GH-11290 and GH-9142: DOMExceptions and segfaults with replaceWith

Author: nielsdos

NEWS

@@ -2,6 +2,10 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? ????, PHP 8.2.8
 
+- DOM:
+  . Fixed bugs GH-11288 and GH-11289 and GH-11290 and GH-9142 (DOMExceptions
+    and segfaults with replaceWith). (nielsdos)
+
 - Opcache:
   . Fix allocation loop in zend_shared_alloc_startup(). (nielsdos)
   . Access violation on smm_shared_globals with ALLOC_FALLBACK. (KoudelkaB)

ext/dom/parentnode.c

@@ -124,6 +124,23 @@ int dom_parent_node_child_element_count(dom_object *obj, zval *retval)
 }
 /* }}} */
 
+static bool dom_is_node_in_list(const zval *nodes, int nodesc, const xmlNodePtr node_to_find)
+{
+	for (int i = 0; i < nodesc; i++) {
+		if (Z_TYPE(nodes[i]) == IS_OBJECT) {
+			const zend_class_entry *ce = Z_OBJCE(nodes[i]);
+
+			if (instanceof_function(ce, dom_node_class_entry)) {
+				if (dom_object_get_node(Z_DOMOBJ_P(nodes + i)) == node_to_find) {
+					return true;
+				}
+			}
+		}
+	}
+
+	return false;
+}
+
 xmlNode* dom_zvals_to_fragment(php_libxml_ref_obj *document, xmlNode *contextNode, zval *nodes, int nodesc)
 {
 	int i;
@@ -177,17 +194,16 @@ xmlNode* dom_zvals_to_fragment(php_libxml_ref_obj *document, xmlNode *contextNod
 					goto hierarchy_request_err;
 				}
 
-				/*
-				 * xmlNewDocText function will always returns same address to the second parameter if the parameters are greater than or equal to three.
-				 * If it's text, that's fine, but if it's an object, it can cause invalid pointer because many new nodes point to the same memory address.
-				 * So we must copy the new node to avoid this situation.
-				 */
-				if (nodesc > 1) {
+				/* Citing from the docs (https://gnome.pages.gitlab.gnome.org/libxml2/devhelp/libxml2-tree.html#xmlAddChild): 
+				 * "Add a new node to @parent, at the end of the child (or property) list merging adjacent TEXT nodes (in which case @cur is freed)".
+				 * So we must take a copy if this situation arises to prevent a use-after-free. */
+				bool will_free = newNode->type == XML_TEXT_NODE && fragment->last && fragment->last->type == XML_TEXT_NODE;
+				if (will_free) {
 					newNode = xmlCopyNode(newNode, 1);
 				}
 
 				if (!xmlAddChild(fragment, newNode)) {
-					if (nodesc > 1) {
+					if (will_free) {
 						xmlFreeNode(newNode);
 					}
 					goto hierarchy_request_err;
@@ -303,25 +319,64 @@ void dom_parent_node_prepend(dom_object *context, zval *nodes, int nodesc)
 	xmlFree(fragment);
 }
 
+static void dom_pre_insert(xmlNodePtr insertion_point, xmlNodePtr parentNode, xmlNodePtr newchild, xmlNodePtr fragment)
+{
+	if (!insertion_point) {
+		/* Place it as last node */
+		if (parentNode->children) {
+			/* There are children */
+			fragment->last->prev = parentNode->last;
+			newchild->prev = parentNode->last->prev;
+			parentNode->last->next = newchild;
+		} else {
+			/* No children, because they moved out when they became a fragment */
+			parentNode->children = newchild;
+			parentNode->last = newchild;
+		}
+	} else {
+		/* Insert fragment before insertion_point */
+		fragment->last->next = insertion_point;
+		if (insertion_point->prev) {
+			insertion_point->prev->next = newchild;
+			newchild->prev = insertion_point->prev;
+		}
+		insertion_point->prev = newchild;
+		if (parentNode->children == insertion_point) {
+			parentNode->children = newchild;
+		}
+	}
+}
+
 void dom_parent_node_after(dom_object *context, zval *nodes, int nodesc)
 {
+	/* Spec link: https://dom.spec.whatwg.org/#dom-childnode-after */
+
 	xmlNode *prevsib = dom_object_get_node(context);
 	xmlNodePtr newchild, parentNode;
-	xmlNode *fragment, *nextsib;
+	xmlNode *fragment;
 	xmlDoc *doc;
-	bool afterlastchild;
-
-	int stricterror = dom_get_strict_error(context->document);
 
-	if (!prevsib->parent) {
-		php_dom_throw_error(NO_MODIFICATION_ALLOWED_ERR, stricterror);
+	/* Spec step 1 */
+	parentNode = prevsib->parent;
+	/* Spec step 2 */
+	if (!parentNode) {
+		int stricterror = dom_get_strict_error(context->document);
+		php_dom_throw_error(HIERARCHY_REQUEST_ERR, stricterror);
 		return;
 	}
 
+	/* Spec step 3: find first following child not in nodes; otherwise null */
+	xmlNodePtr viable_next_sibling = prevsib->next;
+	while (viable_next_sibling) {
+		if (!dom_is_node_in_list(nodes, nodesc, viable_next_sibling)) {
+			break;
+		}
+		viable_next_sibling = viable_next_sibling->next;
+	}
+
 	doc = prevsib->doc;
-	parentNode = prevsib->parent;
-	nextsib = prevsib->next;
-	afterlastchild = (nextsib == NULL);
+
+	/* Spec step 4: convert nodes into fragment */
 	fragment = dom_zvals_to_fragment(context->document, parentNode, nodes, nodesc);
 
 	if (fragment == NULL) {
@@ -331,40 +386,9 @@ void dom_parent_node_after(dom_object *context, zval *nodes, int nodesc)
 	newchild = fragment->children;
 
 	if (newchild) {
-		/* first node and last node are both both parameters to DOMElement::after() method so nextsib and prevsib are null. */
-		if (!parentNode->children) {
-			prevsib = nextsib = NULL;
-		} else if (afterlastchild) {
-			/*
-			 * The new node will be inserted after last node, prevsib is last node.
-			 * The first node is the parameter to DOMElement::after() if parentNode->children == prevsib is true
-			 * and prevsib does not change, otherwise prevsib is parentNode->last (first node).
-			 */
-			prevsib = parentNode->children == prevsib ? prevsib : parentNode->last;
-		} else {
-			/*
-			 * The new node will be inserted after first node, prevsib is first node.
-			 * The first node is not the parameter to DOMElement::after() if parentNode->children == prevsib is true
-			 * and prevsib does not change otherwise prevsib is null to mean that parentNode->children is the new node.
-			 */
-			prevsib = parentNode->children == prevsib ? prevsib : NULL;
-		}
-
-		if (prevsib) {
-			fragment->last->next = prevsib->next;
-			if (prevsib->next) {
-				prevsib->next->prev = fragment->last;
-			}
-			prevsib->next = newchild;
-		} else {
-			parentNode->children = newchild;
-			if (nextsib) {
-				fragment->last->next = nextsib;
-				nextsib->prev = fragment->last;
-			}
-		}
+		/* Step 5: place fragment into the parent before viable_next_sibling */
+		dom_pre_insert(viable_next_sibling, parentNode, newchild, fragment);
 
-		newchild->prev = prevsib;
 		dom_fragment_assign_parent_node(parentNode, fragment);
 		dom_reconcile_ns(doc, newchild);
 	}
@@ -374,17 +398,34 @@ void dom_parent_node_after(dom_object *context, zval *nodes, int nodesc)
 
 void dom_parent_node_before(dom_object *context, zval *nodes, int nodesc)
 {
+	/* Spec link: https://dom.spec.whatwg.org/#dom-childnode-before */
+
 	xmlNode *nextsib = dom_object_get_node(context);
-	xmlNodePtr newchild, prevsib, parentNode;
-	xmlNode *fragment, *afternextsib;
+	xmlNodePtr newchild, parentNode;
+	xmlNode *fragment;
 	xmlDoc *doc;
-	bool beforefirstchild;
 
-	doc = nextsib->doc;
-	prevsib = nextsib->prev;
-	afternextsib = nextsib->next;
+	/* Spec step 1 */
 	parentNode = nextsib->parent;
-	beforefirstchild = !prevsib;
+	/* Spec step 2 */
+	if (!parentNode) {
+		int stricterror = dom_get_strict_error(context->document);
+		php_dom_throw_error(HIERARCHY_REQUEST_ERR, stricterror);
+		return;
+	}
+
+	/* Spec step 3: find first following child not in nodes; otherwise null */
+	xmlNodePtr viable_previous_sibling = nextsib->prev;
+	while (viable_previous_sibling) {
+		if (!dom_is_node_in_list(nodes, nodesc, viable_previous_sibling)) {
+			break;
+		}
+		viable_previous_sibling = viable_previous_sibling->prev;
+	}
+
+	doc = nextsib->doc;
+
+	/* Spec step 4: convert nodes into fragment */
 	fragment = dom_zvals_to_fragment(context->document, parentNode, nodes, nodesc);
 
 	if (fragment == NULL) {
@@ -394,37 +435,14 @@ void dom_parent_node_before(dom_object *context, zval *nodes, int nodesc)
 	newchild = fragment->children;
 
 	if (newchild) {
-		/* first node and last node are both both parameters to DOMElement::before() method so nextsib is null. */
-		if (!parentNode->children) {
-			nextsib = NULL;
-		} else if (beforefirstchild) {
-			/*
-			 * The new node will be inserted before first node, nextsib is first node and afternextsib is last node.
-			 * The first node is not the parameter to DOMElement::before() if parentNode->children == nextsib is true
-			 * and nextsib does not change, otherwise nextsib is the last node.
-			 */
-			nextsib = parentNode->children == nextsib ? nextsib : afternextsib;
-		} else {
-			/*
-			 * The new node will be inserted before last node, prevsib is first node and nestsib is last node.
-			 * The first node is not the parameter to DOMElement::before() if parentNode->children == prevsib is true
-			 * but last node may be, so use prevsib->next to determine the value of nextsib, otherwise nextsib does not change.
-			 */
-			nextsib = parentNode->children == prevsib ? prevsib->next : nextsib;
-		}
-
-		if (parentNode->children == nextsib) {
-			parentNode->children = newchild;
+		/* Step 5: if viable_previous_sibling is null, set it to the parent's first child, otherwise viable_previous_sibling's next sibling */
+		if (!viable_previous_sibling) {
+			viable_previous_sibling = parentNode->children;
 		} else {
-			prevsib->next = newchild;
-		}
-
-		fragment->last->next = nextsib;
-		if (nextsib) {
-			nextsib->prev = fragment->last;
+			viable_previous_sibling = viable_previous_sibling->next;
 		}
-
-		newchild->prev = prevsib;
+		/* Step 6: place fragment into the parent after viable_previous_sibling */
+		dom_pre_insert(viable_previous_sibling, parentNode, newchild, fragment);
 
 		dom_fragment_assign_parent_node(parentNode, fragment);
 		dom_reconcile_ns(doc, newchild);