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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 A9A9CC433E0 for ; Tue, 23 Jun 2020 21:59:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8ADD02078E for ; Tue, 23 Jun 2020 21:59:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388710AbgFWV7J (ORCPT ); Tue, 23 Jun 2020 17:59:09 -0400 Received: from out01.mta.xmission.com ([166.70.13.231]:42034 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387455AbgFWV7J (ORCPT ); Tue, 23 Jun 2020 17:59:09 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out01.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jnqwd-0002ux-QC; Tue, 23 Jun 2020 15:59:07 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95] helo=x220.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.87) (envelope-from ) id 1jnqwc-0000mu-Qc; Tue, 23 Jun 2020 15:59:07 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Cc: , Linus Torvalds , Oleg Nesterov , Jann Horn , Kees Cook , Bernd Edlinger References: <87pn9u6h8c.fsf@x220.int.ebiederm.org> <87r1u5laac.fsf@x220.int.ebiederm.org> Date: Tue, 23 Jun 2020 16:54:43 -0500 In-Reply-To: <87r1u5laac.fsf@x220.int.ebiederm.org> (Eric W. Biederman's message of "Tue, 23 Jun 2020 16:52:43 -0500") Message-ID: <87a70tla70.fsf_-_@x220.int.ebiederm.org> 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=1jnqwc-0000mu-Qc;;;mid=<87a70tla70.fsf_-_@x220.int.ebiederm.org>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1+kkhDUBissrPENOFQGDqoexIjbrQanp20= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: [PATCH v2 3/6] signal: Implement SIGNAL_GROUP_DETHREAD X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org To allow signal_group_exit to be simplfied so that it can only test signal->flags. Add a new flag SIGNAL_GROUP_DETHREAD, that is set and cleared where de_thread sets and clears group_exit_task today. Signed-off-by: "Eric W. Biederman" --- fs/exec.c | 3 +++ include/linux/sched/signal.h | 1 + 2 files changed, 4 insertions(+) diff --git a/fs/exec.c b/fs/exec.c index 33b5d9229c01..9c4c1ab8f715 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1145,6 +1145,7 @@ static int de_thread(struct task_struct *tsk) return -EAGAIN; } + sig->flags |= SIGNAL_GROUP_DETHREAD; sig->group_exit_task = tsk; sig->notify_count = zap_other_threads(tsk); if (!thread_group_leader(tsk)) @@ -1244,6 +1245,7 @@ static int de_thread(struct task_struct *tsk) } spin_lock_irq(lock); + sig->flags &= ~SIGNAL_GROUP_DETHREAD; sig->group_exit_task = NULL; sig->notify_count = 0; spin_unlock_irq(lock); @@ -1259,6 +1261,7 @@ static int de_thread(struct task_struct *tsk) /* protects against exit_notify() and __exit_signal() */ read_lock_irq(&tasklist_lock); spin_lock(lock); + sig->flags &= ~SIGNAL_GROUP_DETHREAD; sig->group_exit_task = NULL; sig->notify_count = 0; spin_unlock(lock); diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index b4f36a11be5e..5ff8697b21cd 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -253,6 +253,7 @@ struct signal_struct { /* Signal group actions. */ #define SIGNAL_GROUP_EXIT 0x00000100 /* group exit in progress */ #define SIGNAL_GROUP_COREDUMP 0x00000200 /* coredump in progress */ +#define SIGNAL_GROUP_DETHREAD 0x00000400 /* exec de_thread in progress */ /* Flags applicable to the entire signal group. */ #define SIGNAL_UNKILLABLE 0x00001000 /* for init: ignore fatal signals */ -- 2.20.1