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 X-Spam-Level: X-Spam-Status: No, score=-13.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0E501C49EA6 for ; Thu, 24 Jun 2021 19:03:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DC85F613DC for ; Thu, 24 Jun 2021 19:03:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232739AbhFXTF7 (ORCPT ); Thu, 24 Jun 2021 15:05:59 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:56404 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232417AbhFXTFy (ORCPT ); Thu, 24 Jun 2021 15:05:54 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out02.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1lwUdS-00GQKH-Ps; Thu, 24 Jun 2021 13:03:34 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95]:47224 helo=email.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1lwUdR-003Hft-BL; Thu, 24 Jun 2021 13:03:34 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Linus Torvalds Cc: Al Viro , Michael Schmitz , linux-arch , Jens Axboe , Oleg Nesterov , Linux Kernel Mailing List , Richard Henderson , Ivan Kokshaysky , Matt Turner , alpha , Geert Uytterhoeven , linux-m68k , Arnd Bergmann , Ley Foon Tan , Tejun Heo , Kees Cook References: <87sg1lwhvm.fsf@disp2133> <6e47eff8-d0a4-8390-1222-e975bfbf3a65@gmail.com> <924ec53c-2fd9-2e1c-bbb1-3fda49809be4@gmail.com> <87eed4v2dc.fsf@disp2133> <5929e116-fa61-b211-342a-c706dcb834ca@gmail.com> <87fsxjorgs.fsf@disp2133> <87a6njf0ia.fsf@disp2133> <87tulpbp19.fsf@disp2133> <87zgvgabw1.fsf@disp2133> <875yy3850g.fsf_-_@disp2133> Date: Thu, 24 Jun 2021 14:03:25 -0500 In-Reply-To: <875yy3850g.fsf_-_@disp2133> (Eric W. Biederman's message of "Thu, 24 Jun 2021 13:57:35 -0500") Message-ID: <87pmwb5blu.fsf_-_@disp2133> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-SPF: eid=1lwUdR-003Hft-BL;;;mid=<87pmwb5blu.fsf_-_@disp2133>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1+ubskzIAw9Nf7jzRrS5tUdPBJdmYtDWnM= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: [PATCH 8/9] signal/task_exit: Use start_task_exit in place of do_exit X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Reuse start_task_exit_locked to implement start_task_exit. Simplify the exit logic by having all exits go through get_signal. This simplifies the analysis of syncrhonization during exit and gurantees a full set of registers will be available for ptrace to examine at PTRACE_EVENT_EXIT. Signed-off-by: "Eric W. Biederman" --- include/linux/sched/signal.h | 1 + kernel/exit.c | 4 +++- kernel/seccomp.c | 2 +- kernel/signal.c | 12 ++++++++++++ 4 files changed, 17 insertions(+), 2 deletions(-) diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index a958381ba4a9..3f4e69c019b7 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -430,6 +430,7 @@ static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) void start_group_exit(int exit_code); void start_task_exit_locked(struct task_struct *task, int exit_code); +void start_task_exit(int exit_code); void task_join_group_stop(struct task_struct *task); diff --git a/kernel/exit.c b/kernel/exit.c index 635f434122b7..51e0c82b3f7d 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -889,7 +889,9 @@ EXPORT_SYMBOL(complete_and_exit); SYSCALL_DEFINE1(exit, int, error_code) { - do_exit((error_code&0xff)<<8); + start_task_exit((error_code&0xff)<<8); + /* get_signal will call do_exit */ + return 0; } diff --git a/kernel/seccomp.c b/kernel/seccomp.c index b1c06fd1b205..e0c4c123a8bf 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -1248,7 +1248,7 @@ static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd, force_sig_seccomp(this_syscall, data, true); } else { if (action == SECCOMP_RET_KILL_THREAD) - do_exit(SIGSYS); + start_task_exit(SIGSYS); else start_group_exit(SIGSYS); } diff --git a/kernel/signal.c b/kernel/signal.c index afbc001220dd..63fda9b6bbf9 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1424,6 +1424,18 @@ void start_task_exit_locked(struct task_struct *task, int exit_code) } } +void start_task_exit(int exit_code) +{ + struct task_struct *task = current; + if (!fatal_signal_pending(task)) { + struct sighand_struct *const sighand = task->sighand; + spin_lock_irq(&sighand->siglock); + if (!fatal_signal_pending(current)) + start_task_exit_locked(task, exit_code); + spin_unlock_irq(&sighand->siglock); + } +} + struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, unsigned long *flags) { -- 2.20.1