From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B197FC54EE1 for ; Fri, 20 Jan 2023 14:45:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230507AbjATOpI (ORCPT ); Fri, 20 Jan 2023 09:45:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50430 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230456AbjATOpC (ORCPT ); Fri, 20 Jan 2023 09:45:02 -0500 Received: from mail-io1-xd44.google.com (mail-io1-xd44.google.com [IPv6:2607:f8b0:4864:20::d44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1832BCFD26; Fri, 20 Jan 2023 06:44:38 -0800 (PST) Received: by mail-io1-xd44.google.com with SMTP id q130so2537422iod.4; Fri, 20 Jan 2023 06:44:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=hDCYG8WxS/pUjt/n8MvGqQ4mEBFsqI4uxAOlI7paeNc=; b=ZKv2kJnbHZoYZy1tJyO4tdeh91R61byMjNI2lb14x8KJae1X5W0y4SjIBSNS1kHRdb oigCmrD81gGVVGUbcrqhcIFKQz6nDsSr5DazytIj3JGvflF/m2P6KyFYPTlTVvVuTxKF +CCZvCHJ20T0wdFaUFkadoTZO92RW8K6iiqfnrrGwPtJz5XlVdOVELQkcnQwSlf8vekW jLCkuE7eZFleOD4LEysRktAkKxR/OUdQDMYlodZFOEgM2s3cv73ohw2KPUYkZVt3G/ct 2WD1tWGgvuTcdRDQ8D6tW9faTAs/szW+tedVcUEXKO15Ibc57FL/ptN/1uFkGrw3wXIz pqzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=hDCYG8WxS/pUjt/n8MvGqQ4mEBFsqI4uxAOlI7paeNc=; b=a1hcwUn/ThxYlF+tuzUb2bA5ERssRJcEX+0n+IZZ8iYCf67WCeSePo4CAoBrmyc6vS ymY8EUbAz6Ur6ZhtUd/PGeEfDJYriVKDPkzBUr0IhZ0vmi3h8cW3FBaN1lS2hbiFzyN3 4P8NuKgJD7LOM0lArSelE1kkS8L9dfkSls6uxrB70/fpWdcFhBRKlN2CbPtXtPKxq75G Hfn4QyEDJbRrY3b0Y3hXfasHCTFXHPetS+7Hq2x/knELXQJO2fhCw8Pd1LneR6k/E34B JPD52OpBXb04X6b4/sGJyrr78MTbeTqqZzIIP+sk6fHZNQuJXFRs1KNyg1HFbzjkcaBi JXEA== X-Gm-Message-State: AFqh2koFdht3Qx1OpBMLifFfRDlOkhQjvw3xqWI5cdw8Q+CWxBIZbRZT knKbX+9ea2jTv7fSyZFCFb3TpTVunD68 X-Google-Smtp-Source: AMrXdXuMycxFXCNiEYKeHDhmhI7Qlr14maanOHP2VLUa80rQsKw4EVW4q2yPZ6+LLLQfFL6ThMcBsA== X-Received: by 2002:a5d:8348:0:b0:6e3:c112:3339 with SMTP id q8-20020a5d8348000000b006e3c1123339mr9578231ior.16.1674225846816; Fri, 20 Jan 2023 06:44:06 -0800 (PST) Received: from fedora.mshome.net ([104.184.156.161]) by smtp.gmail.com with ESMTPSA id p185-20020a0229c2000000b003a7c47efde0sm1513852jap.11.2023.01.20.06.44.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Jan 2023 06:44:06 -0800 (PST) From: Gregory Price X-Google-Original-From: Gregory Price To: linux-kernel@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, krisman@collabora.com, tglx@linutronix.de, luto@kernel.org, oleg@redhat.com, peterz@infradead.org, ebiederm@xmission.com, akpm@linux-foundation.org, adobriyan@gmail.com, corbet@lwn.net, shuah@kernel.org, Gregory Price Subject: [PATCH v3 0/3] Checkpoint Support for Syscall User Dispatch Date: Fri, 20 Jan 2023 09:43:53 -0500 Message-Id: <20230120144356.40717-1-gregory.price@memverge.com> X-Mailer: git-send-email 2.39.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org v3: Kernel test robot static function fix Whitespace nitpicks v2: Implements the getter/setter interface in ptrace rather than prctl Syscall user dispatch makes it possible to cleanly intercept system calls from user-land. However, most transparent checkpoint software presently leverages some combination of ptrace and system call injection to place software in a ready-to-checkpoint state. If Syscall User Dispatch is enabled at the time of being quiesced, injected system calls will subsequently be interposed upon and dispatched to the task's signal handler. This patch set implements 3 features to enable software such as CRIU to cleanly interpose upon software leveraging syscall user dispatch. - Implement PTRACE_O_SUSPEND_SYSCALL_USER_DISPATCH, akin to a similar feature for SECCOMP. This allows a ptracer to temporarily disable syscall user dispatch, making syscall injection possible. - Implement an fs/proc extension that reports whether Syscall User Dispatch is being used in proc/status. A similar value is present for SECCOMP, and is used to determine whether special logic is needed during checkpoint/resume. - Implement a getter interface for Syscall User Dispatch config info. To resume successfully, the checkpoint/resume software has to save and restore this information. Presently this configuration is write-only, with no way for C/R software to save it. This was done in ptrace because syscall user dispatch is not part of uapi. The syscall_user_dispatch_config structure was added to the ptrace exports. Gregory Price (3): ptrace,syscall_user_dispatch: Implement Syscall User Dispatch Suspension fs/proc/array: Add Syscall User Dispatch to proc status ptrace,syscall_user_dispatch: add a getter/setter for sud configuration .../admin-guide/syscall-user-dispatch.rst | 5 +- fs/proc/array.c | 8 +++ include/linux/ptrace.h | 2 + include/linux/syscall_user_dispatch.h | 19 +++++++ include/uapi/linux/ptrace.h | 16 +++++- kernel/entry/syscall_user_dispatch.c | 54 +++++++++++++++++++ kernel/ptrace.c | 13 +++++ 7 files changed, 115 insertions(+), 2 deletions(-) -- 2.39.0