Fixed bug #79468

Close the stream filter resources when removing them from the stream.

Author: 769344359

NEWS

@@ -3,6 +3,8 @@ PHP                                                                        NEWS
 ?? ??? 2020, PHP 7.2.30
 
 - Standard:
+  . Fixed bug #79468 (SIGSEGV when closing stream handle with a stream filter
+    appended). (dinosaur)
   . Fixed bug #79330 (shell_exec() silently truncates after a null byte). (stas)
   . Fixed bug #79465 (OOB Read in urldecode()). (stas)
 

ext/standard/tests/filters/bug79468.phpt

@@ -0,0 +1,21 @@
+--TEST--
+Bug #79468	SIGSEGV when closing stream handle with a stream filter appended
+--SKIPIF--
+<?php
+$filters = stream_get_filters();
+if(! in_array( "string.rot13", $filters )) die( "skip rot13 filter not available." );
+?>
+--FILE--
+<?php
+$fp = fopen('php://temp', 'rb');
+$rot13_filter = stream_filter_append($fp, "string.rot13", STREAM_FILTER_WRITE);
+fwrite($fp, "This is ");
+fclose($fp);
+try {
+    stream_filter_remove($rot13_filter);
+} catch (\Throwable $e) {
+    var_dump($e->getMessage());
+}
+?>
+--EXPECTF--
+Warning: stream_filter_remove(): Invalid resource given, not a stream filter in %s on line %d

main/streams/streams.c

@@ -477,9 +477,15 @@ fprintf(stderr, "stream_free: %s:%p[%s] preserve_handle=%d release_cast=%d remov
 
 	if (close_options & PHP_STREAM_FREE_RELEASE_STREAM) {
 		while (stream->readfilters.head) {
+			if (stream->readfilters.head->res != NULL) {
+				zend_list_close(stream->readfilters.head->res);
+			}
 			php_stream_filter_remove(stream->readfilters.head, 1);
 		}
 		while (stream->writefilters.head) {
+			if (stream->writefilters.head->res != NULL) {
+				zend_list_close(stream->writefilters.head->res);
+			}
 			php_stream_filter_remove(stream->writefilters.head, 1);
 		}