From patchwork Fri Aug 18 14:26:05 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?b?THVrw6HFoSBEb2t0b3I=?= X-Patchwork-Id: 9909259 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D87AE60382 for ; Fri, 18 Aug 2017 14:31:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C332028CCE for ; Fri, 18 Aug 2017 14:31:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B7E6928CE1; Fri, 18 Aug 2017 14:31:03 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 42B2828CCE for ; Fri, 18 Aug 2017 14:31:03 +0000 (UTC) Received: from localhost ([::1]:57792 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1diiIV-0002OG-1d for patchwork-qemu-devel@patchwork.kernel.org; Fri, 18 Aug 2017 10:30:51 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58201) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1diiEl-0000AZ-D3 for qemu-devel@nongnu.org; Fri, 18 Aug 2017 10:27:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1diiEk-0007ac-BU for qemu-devel@nongnu.org; Fri, 18 Aug 2017 10:26:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39348) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1diiEk-0007Wc-4x for qemu-devel@nongnu.org; Fri, 18 Aug 2017 10:26:58 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2E8FB883C7; Fri, 18 Aug 2017 14:26:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 2E8FB883C7 Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=ldoktor@redhat.com Received: from localhost.localdomain.com (unknown [10.40.205.27]) by smtp.corp.redhat.com (Postfix) with ESMTP id ADA5566D76; Fri, 18 Aug 2017 14:26:50 +0000 (UTC) From: =?UTF-8?q?Luk=C3=A1=C5=A1=20Doktor?= To: qemu-devel@nongnu.org Date: Fri, 18 Aug 2017 16:26:05 +0200 Message-Id: <20170818142613.32394-3-ldoktor@redhat.com> In-Reply-To: <20170818142613.32394-1-ldoktor@redhat.com> References: <20170818142613.32394-1-ldoktor@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 18 Aug 2017 14:26:57 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v6 02/10] qemu|qtest: Avoid dangerous arguments X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ldoktor@redhat.com, famz@redhat.com, ehabkost@redhat.com, apahim@redhat.com, armbru@redhat.com, mreitz@redhat.com, jsnow@redhat.com, f4bug@amsat.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP The list object is mutable in python and potentially might modify other object's arguments when used as default argument. Reproducer: >>> vm1 = QEMUMachine("qemu") >>> vm2 = QEMUMachine("qemu") >>> vm1._wrapper.append("foo") >>> print vm2._wrapper ['foo'] In this case the `args` is actually copied so it would be safe to keep it, but it's not a good practice to keep it. The same issue applies in inherited qtest module. Signed-off-by: Lukáš Doktor Reviewed-by: Eduardo Habkost Reviewed-by: John Snow Reviewed-by: Cleber Rosa --- scripts/qemu.py | 6 +++++- scripts/qtest.py | 2 +- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/scripts/qemu.py b/scripts/qemu.py index dd679f1..5d09de4 100644 --- a/scripts/qemu.py +++ b/scripts/qemu.py @@ -23,7 +23,7 @@ import qmp.qmp class QEMUMachine(object): '''A QEMU VM''' - def __init__(self, binary, args=[], wrapper=[], name=None, + def __init__(self, binary, args=None, wrapper=None, name=None, test_dir="/var/tmp", monitor_address=None, socket_scm_helper=None, debug=False): ''' @@ -39,6 +39,10 @@ class QEMUMachine(object): @param debug: enable debug mode @note: Qemu process is not started until launch() is used. ''' + if args is None: + args = [] + if wrapper is None: + wrapper = [] if name is None: name = "qemu-%d" % os.getpid() if monitor_address is None: diff --git a/scripts/qtest.py b/scripts/qtest.py index d5aecb5..ab183c0 100644 --- a/scripts/qtest.py +++ b/scripts/qtest.py @@ -79,7 +79,7 @@ class QEMUQtestProtocol(object): class QEMUQtestMachine(qemu.QEMUMachine): '''A QEMU VM''' - def __init__(self, binary, args=[], name=None, test_dir="/var/tmp", + def __init__(self, binary, args=None, name=None, test_dir="/var/tmp", socket_scm_helper=None): if name is None: name = "qemu-%d" % os.getpid()