Fix memory leak

ext/dom/document.c

@@ -2175,11 +2175,16 @@ PHP_FUNCTION(dom_document_save_html)
 		}
 
 		buf = xmlBufferCreate();
-		outBuf = xmlOutputBufferCreateBuffer(buf, NULL);
-		if (!outBuf || !buf) {
+		if (!buf) {
 			php_error_docref(NULL, E_WARNING, "Could not fetch buffer");
 			RETURN_FALSE;
 		}
+		outBuf = xmlOutputBufferCreateBuffer(buf, NULL);
+		if (!outBuf) {
+			xmlBufferFree(buf);
+			php_error_docref(NULL, E_WARNING, "Could not fetch output buffer");
+			RETURN_FALSE;
+		}
 
 		if (node->type == XML_DOCUMENT_FRAG_NODE) {
 			for (node = node->children; node; node = node->next) {
@@ -2205,6 +2210,7 @@ PHP_FUNCTION(dom_document_save_html)
 			RETVAL_FALSE;
 		}
 		xmlOutputBufferClose(outBuf);
+		xmlBufferFree(buf);
 	} else {
 		int size = 0;
 #if LIBXML_VERSION >= 20623