From patchwork Tue Jun 23 21:56:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 11621881 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5B87290 for ; Tue, 23 Jun 2020 22:00:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4D62320675 for ; Tue, 23 Jun 2020 22:00:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388366AbgFWWAt (ORCPT ); Tue, 23 Jun 2020 18:00:49 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:58744 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388125AbgFWWAs (ORCPT ); Tue, 23 Jun 2020 18:00:48 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]) by out02.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jnqyF-0004gJ-GE; Tue, 23 Jun 2020 16:00:47 -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 1jnqyE-00011w-IF; Tue, 23 Jun 2020 16:00:47 -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 16:56:23 -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: <87sgeljvjs.fsf_-_@x220.int.ebiederm.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1jnqyE-00011w-IF;;;mid=<87sgeljvjs.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//9RpPvm0Ju/m/af9xHXdmD0J+69ybl0M= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on sa07.xmission.com X-Spam-Level: X-Spam-Status: No, score=0.5 required=8.0 tests=ALL_TRUSTED,BAYES_50, DCC_CHECK_NEGATIVE,T_TooManySym_01,XMSubLong autolearn=disabled version=3.4.2 X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.8 BAYES_50 BODY: Bayes spam probability is 40 to 60% * [score: 0.5000] * 0.7 XMSubLong Long Subject * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa07 0; Body=1 Fuz1=1 Fuz2=1] * 0.0 T_TooManySym_01 4+ unique symbols in subject X-Spam-DCC: ; sa07 0; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ; X-Spam-Relay-Country: X-Spam-Timing: total 543 ms - load_scoreonly_sql: 0.10 (0.0%), signal_user_changed: 11 (2.1%), b_tie_ro: 10 (1.8%), parse: 1.15 (0.2%), extract_message_metadata: 19 (3.4%), get_uri_detail_list: 3.2 (0.6%), tests_pri_-1000: 24 (4.3%), tests_pri_-950: 1.34 (0.2%), tests_pri_-900: 1.12 (0.2%), tests_pri_-90: 159 (29.2%), check_bayes: 157 (28.9%), b_tokenize: 17 (3.1%), b_tok_get_all: 9 (1.6%), b_comp_prob: 4.3 (0.8%), b_tok_touch_all: 123 (22.6%), b_finish: 1.00 (0.2%), tests_pri_0: 313 (57.7%), check_dkim_signature: 0.82 (0.2%), check_dkim_adsp: 2.2 (0.4%), poll_dns_idle: 0.53 (0.1%), tests_pri_10: 2.2 (0.4%), tests_pri_500: 7 (1.3%), rewrite_mail: 0.00 (0.0%) Subject: [PATCH v2 6/6] exec: Rename group_exit_task group_exec_task and correct the Documentation X-Spam-Flag: No 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-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Rename group_exit_task to group_exec_task to make it clear this field is only used during exec. Update the comments for the fields group_exec_task and notify_count as they are only used by exec. Notifications to the execing task aka group_exec_task happen at 0 and -1. Signed-off-by: "Eric W. Biederman" --- fs/exec.c | 8 ++++---- include/linux/sched/signal.h | 11 ++++------- kernel/exit.c | 4 ++-- 3 files changed, 10 insertions(+), 13 deletions(-) diff --git a/fs/exec.c b/fs/exec.c index 9c4c1ab8f715..c594af64acd2 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1146,7 +1146,7 @@ static int de_thread(struct task_struct *tsk) } sig->flags |= SIGNAL_GROUP_DETHREAD; - sig->group_exit_task = tsk; + sig->group_exec_task = tsk; sig->notify_count = zap_other_threads(tsk); if (!thread_group_leader(tsk)) sig->notify_count--; @@ -1175,7 +1175,7 @@ static int de_thread(struct task_struct *tsk) spin_lock(lock); /* * Do this under tasklist_lock to ensure that - * exit_notify() can't miss ->group_exit_task + * exit_notify() can't miss ->group_exec_task */ sig->notify_count = -1; if (likely(leader->exit_state)) @@ -1246,7 +1246,7 @@ static int de_thread(struct task_struct *tsk) spin_lock_irq(lock); sig->flags &= ~SIGNAL_GROUP_DETHREAD; - sig->group_exit_task = NULL; + sig->group_exec_task = NULL; sig->notify_count = 0; spin_unlock_irq(lock); @@ -1262,7 +1262,7 @@ static int de_thread(struct task_struct *tsk) read_lock_irq(&tasklist_lock); spin_lock(lock); sig->flags &= ~SIGNAL_GROUP_DETHREAD; - sig->group_exit_task = NULL; + sig->group_exec_task = NULL; sig->notify_count = 0; spin_unlock(lock); read_unlock_irq(&tasklist_lock); diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index 43822e2b63e6..ad6b209b1363 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -98,13 +98,10 @@ struct signal_struct { /* thread group exit support */ int group_exit_code; - /* overloaded: - * - notify group_exit_task when ->count is equal to notify_count - * - everyone except group_exit_task is stopped during signal delivery - * of fatal signals, group_exit_task processes the signal. - */ + + /* exec support, notify group_exec_task when notify_count is 0 or -1 */ int notify_count; - struct task_struct *group_exit_task; + struct task_struct *group_exec_task; /* thread group stop support, overloads group_exit_code too */ int group_stop_count; @@ -265,7 +262,7 @@ static inline void signal_set_stop_flags(struct signal_struct *sig, sig->flags = (sig->flags & ~SIGNAL_STOP_MASK) | flags; } -/* If true, all threads except ->group_exit_task have pending SIGKILL */ +/* If true, all threads except ->group_exec_task have pending SIGKILL */ static inline int signal_group_exit(const struct signal_struct *sig) { return (sig->flags & (SIGNAL_GROUP_EXIT | diff --git a/kernel/exit.c b/kernel/exit.c index 727150f28103..4206d33b4904 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -115,7 +115,7 @@ static void __exit_signal(struct task_struct *tsk) * then notify it: */ if (sig->notify_count > 0 && !--sig->notify_count) - wake_up_process(sig->group_exit_task); + wake_up_process(sig->group_exec_task); if (tsk == sig->curr_target) sig->curr_target = next_thread(tsk); @@ -672,7 +672,7 @@ static void exit_notify(struct task_struct *tsk, int group_dead) /* mt-exec, de_thread() is waiting for group leader */ if (unlikely(tsk->signal->notify_count < 0)) - wake_up_process(tsk->signal->group_exit_task); + wake_up_process(tsk->signal->group_exec_task); write_unlock_irq(&tasklist_lock); list_for_each_entry_safe(p, n, &dead, ptrace_entry) {