Fix #77919: Potential UAF in Phar RSHUTDOWN

We have to properly clean up in case phar_flush() is failing.

We also make the expectation of the respective test case less liberal
to avoid missing such bugs in the future.

NEWS

@@ -10,6 +10,9 @@ PHP                                                                        NEWS
   (CVE-2019-11042) (Stas)
   . Fixed bug #78222 (heap-buffer-overflow on exif_scan_thumbnail).
   (CVE-2019-11041) (Stas)
+  
+- Phar:
+  . Fixed bug #77919 (Potential UAF in Phar RSHUTDOWN). (cmb)
 
 30 May 2019, PHP 7.1.30
 

ext/phar/phar_object.c

@@ -2037,7 +2037,7 @@ static zend_object *phar_rename_archive(phar_archive_data **sphar, char *ext, ze
 	char *newname = NULL, *newpath = NULL;
 	zval ret, arg1;
 	zend_class_entry *ce;
-	char *error;
+	char *error = NULL;
 	const char *pcr_error;
 	int ext_len = ext ? strlen(ext) : 0;
 	size_t new_len, oldname_len;
@@ -2205,6 +2205,8 @@ its_ok:
 	phar_flush(phar, 0, 0, 1, &error);
 
 	if (error) {
+		zend_hash_str_del(&(PHAR_G(phar_fname_map)), newpath, phar->fname_len);
+		*sphar = NULL;
 		zend_throw_exception_ex(spl_ce_BadMethodCallException, 0, "%s", error);
 		efree(error);
 		efree(oldpath);

ext/phar/tests/bug71488.phpt

@@ -15,4 +15,7 @@ DONE
 ?>
 --EXPECTF--
 Fatal error: Uncaught BadMethodCallException: tar-based phar "%s/bug71488.test" cannot be created, link "%s" is too long for format in %sbug71488.php:%d
-Stack trace:%A
+Stack trace:
+#0 %s(%d): PharData->decompress('test')
+#1 {main}
+  thrown in %s on line %d