Sitemaps: Prevent invalid provider names throwing errors.

Validate the requested sitemap is a string before attempting to use it in a provider. This prevents `WP_Sitemaps_Registry::get_provider()` from triggering a fatal error in more recent versions of PHP.

The errors can be triggered by items outside the site owner or developers control (such as a user visiting `?sitemap[foo]=bar`) so the code fails silently to avoid filling error logs with unfixable errors.

Props costdev, dd32.
Fixes #56336.

Built from https://develop.svn.wordpress.org/trunk@53838


git-svn-id: http://core.svn.wordpress.org/trunk@53397 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/sitemaps/class-wp-sitemaps-registry.php

@@ -65,7 +65,7 @@ class WP_Sitemaps_Registry {
 	 * @return WP_Sitemaps_Provider|null Sitemap provider if it exists, null otherwise.
 	 */
 	public function get_provider( $name ) {
-		if ( ! isset( $this->providers[ $name ] ) ) {
+		if ( ! is_string( $name ) || ! isset( $this->providers[ $name ] ) ) {
 			return null;
 		}
 

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.1-alpha-53837';
+$wp_version = '6.1-alpha-53838';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.