Fixed GH-18267 finfo_file() crashing on invalid URL protocol.

Author: devnexen

ext/fileinfo/fileinfo.c

@@ -283,7 +283,6 @@ static const char* php_fileinfo_from_path(struct magic_set *magic, const zend_st
 	ZEND_ASSERT(path);
 	ZEND_ASSERT(ZSTR_LEN(path) != 0);
 	ZEND_ASSERT(!zend_str_has_nul_byte(path));
-	ZEND_ASSERT(context != NULL);
 
 	/* determine if the file is a local file or remote URL */
 	const char *dummy;
@@ -293,6 +292,8 @@ static const char* php_fileinfo_from_path(struct magic_set *magic, const zend_st
 	if (UNEXPECTED(wrap == NULL)) {
 		return NULL;
 	}
+	/* we need the stream context when there is an appropriate URL protocol */
+	ZEND_ASSERT(context != NULL);
 
 #ifdef PHP_WIN32
 	if (php_stream_stat_path_ex(ZSTR_VAL(path), 0, &ssb, context) == SUCCESS) {