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[2620:137:e000::1:20]) by mx.google.com with ESMTP id hw9-20020a170907a0c900b00791a3dd01b1si10875694ejc.865.2022.10.22.05.35.57; Sat, 22 Oct 2022 05:36:22 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@lirui.org header.s=key1 header.b=FH8LkjeN; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=QUARANTINE sp=QUARANTINE dis=NONE) header.from=lirui.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229905AbiJVMGe (ORCPT + 99 others); Sat, 22 Oct 2022 08:06:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45602 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229535AbiJVMGc (ORCPT ); Sat, 22 Oct 2022 08:06:32 -0400 Received: from out2.migadu.com (out2.migadu.com [IPv6:2001:41d0:2:aacc::]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A34B3237FB5; Sat, 22 Oct 2022 05:06:27 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lirui.org; s=key1; t=1666440385; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=Nc63P9hRTQ/Z/eSeuCo+wraUic53v2hR6RRkGzpw6/o=; b=FH8LkjeN6X1aOippPiAt6lAMO3BdihGUSOP+TV97NxowGjFjYf9IbCytf+g4W7DTGULDe6 SPZqgu7QkS151ixVQ6Lw5zHnCZnu8mh/6bOGuTKi5kb5A8E+xiGnpsIlVD0dz7M3MY7ZfR N7li2ZQLnQMn5pEV7ZOMYraFg4Je9fDekAaQWgVgUfRAYy11DW0B9MXvOtbKebCoe0qjTa bbrOvJxjtHG0ND5SmsJ02hCreeO+6Q3jEjJEqkboZm/LwjJhLFdNkQ21BaRp2ijVyuHVnW I5vtEK6juPKFwGm0TqrzuYbvrM2x6N12vectSwDlhaPb33kFBfXf63HjsSyJWg== From: Rui Li To: Alex Shi , Yanteng Si Cc: Jonathan Corbet , Wu XiangCheng , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Rui Li Subject: [PATCH] docs/zh_CN: Add userspace-api/no_new_privs Chinese translation Date: Sat, 22 Oct 2022 20:05:57 +0800 Message-Id: <20221022120557.381115-1-me@lirui.org> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Spam-Status: No, score=-0.1 required=5.0 tests=BAYES_50,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW,SPF_HELO_PASS, SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1747391278439698412?= X-GMAIL-MSGID: =?utf-8?q?1747391278439698412?= Translate the following documents into Chinese: - userspace-api/no_new_privs.rst Signed-off-by: Rui Li Reviewed-by: Yanteng Si --- .../zh_CN/userspace-api/index.rst | 2 +- .../zh_CN/userspace-api/no_new_privs.rst | 57 +++++++++++++++++++ 2 files changed, 58 insertions(+), 1 deletion(-) create mode 100644 Documentation/translations/zh_CN/userspace-api/no_new_privs.rst diff --git a/Documentation/translations/zh_CN/userspace-api/index.rst b/Documentation/translations/zh_CN/userspace-api/index.rst index 12c63d81c663..6a7e82ac16b9 100644 --- a/Documentation/translations/zh_CN/userspace-api/index.rst +++ b/Documentation/translations/zh_CN/userspace-api/index.rst @@ -25,10 +25,10 @@ Linux 内核用户空间API指南 :maxdepth: 2 ebpf/index + no_new_privs TODOList: -* no_new_privs * seccomp_filter * landlock * unshare diff --git a/Documentation/translations/zh_CN/userspace-api/no_new_privs.rst b/Documentation/translations/zh_CN/userspace-api/no_new_privs.rst new file mode 100644 index 000000000000..81bd16ce3ad2 --- /dev/null +++ b/Documentation/translations/zh_CN/userspace-api/no_new_privs.rst @@ -0,0 +1,57 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: ../disclaimer-zh_CN.rst + +:Original: Documentation/userspace-api/no_new_privs.rst + +:翻译: + + 李睿 Rui Li + +============ +无新权限标志 +============ + +execve系统调用可以给一个新启动的程序授予它的父程序本没有的权限。最明显的两个 +例子就是setuid/setgid控制程序和文件的能力。为了避免父程序也获得这些权限，内 +核和用户代码必须小心避免任何父程序可以颠覆子程序的情况。比如： + + - 程序在setuid后，动态装载器处理 ``LD_*`` 环境变量的不同方式。 + + - 对于非特权程序，chroot是不允许的，因为这会允许 ``/etc/passwd`` 在继承 + chroot的程序眼中被替换。 + + - 执行代码对ptrace有特殊处理。 + +这些都是临时性的修复。 ``no_new_privs`` 位（从 Linux 3.5 起）是一个新的通 +用的机制来保证一个进程安全地修改其执行环境并跨execve持久化。任何任务都可以设 +置 ``no_new_privs`` 。一旦该位被设置，它会在fork、clone和execve中继承下去 +，并且不能被撤销。在 ``no_new_privs`` 被设置的情况下， ``execve()`` 将保证 +不会授予权限去做任何没有execve调用就不能做的事情。比如， setuid 和 setgid +位不会再改变 uid 或 gid；文件能力不会被添加到授权集合中，并且Linux安全模块（ +LSM）不会在execve调用后放松限制。 + +设置 ``no_new_privs`` 使用:: + + prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); + +不过要小心，Linux安全模块（LSM）也可能不会在 ``no_new_privs`` 模式下收紧约束。 +（这意味着一个一般的服务启动器在执行守护进程前就去设置 ``no_new_privs`` 可能 +会干扰基于LSM的沙箱。） + +请注意， ``no_new_privs`` 并不能阻止不涉及 ``execve()`` 的权限变化。一个拥有 +适当权限的任务仍然可以调用 ``setuid(2)`` 并接收 SCM_RIGHTS 数据报。 + +目前来说， ``no_new_privs`` 有两大使用场景： + + - 为seccomp模式2沙箱安装的过滤器会跨execve持久化，并能够改变新执行程序的行为。 + 非特权用户因此在 ``no_new_privs`` 被设置的情况下只允许安装这样的过滤器。 + + - ``no_new_privs`` 本身就能被用于减少非特权用户的攻击面。如果所有以某个 uid + 运行的程序都设置了 ``no_new_privs`` ，那么那个 uid 将无法通过攻击 setuid， + setgid 和使用文件能力的二进制来提权；它需要先攻击一些没有被设置 ``no_new_privs`` + 位的东西。 + +将来，其他潜在的危险的内核特性可能被非特权任务利用，即使 ``no_new_privs`` 被置位。 +原则上，当 ``no_new_privs`` 被置位时， ``unshare(2)`` 和 ``clone(2)`` 的几个选 +项将是安全的，并且 ``no_new_privs`` 加上 ``chroot`` 是可以被认为比 chroot本身危 +险性小得多的。