From patchwork Fri Jun 7 21:43:21 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 10982791 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 77EE914B6 for ; Fri, 7 Jun 2019 21:43:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 671E428BA7 for ; Fri, 7 Jun 2019 21:43:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5ADBC28BDA; Fri, 7 Jun 2019 21:43:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E55FF28BD4 for ; Fri, 7 Jun 2019 21:43:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730937AbfFGVng (ORCPT ); Fri, 7 Jun 2019 17:43:36 -0400 Received: from out01.mta.xmission.com ([166.70.13.231]:53807 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730527AbfFGVng (ORCPT ); Fri, 7 Jun 2019 17:43:36 -0400 Received: from in01.mta.xmission.com ([166.70.13.51]) by out01.mta.xmission.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.87) (envelope-from ) id 1hZMe6-0008BU-It; Fri, 07 Jun 2019 15:43:34 -0600 Received: from ip72-206-97-68.om.om.cox.net ([72.206.97.68] helo=x220.xmission.com) by in01.mta.xmission.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.87) (envelope-from ) id 1hZMe5-00007T-Gx; Fri, 07 Jun 2019 15:43:34 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Oleg Nesterov Cc: Andrew Morton , Deepa Dinamani , linux-kernel@vger.kernel.org, arnd@arndb.de, dbueso@suse.de, axboe@kernel.dk, dave@stgolabs.net, e@80x24.org, jbaron@akamai.com, linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, omar.kilani@gmail.com, tglx@linutronix.de, Al Viro , Linus Torvalds , David Laight , References: <20190522032144.10995-1-deepa.kernel@gmail.com> <20190529161157.GA27659@redhat.com> <20190604134117.GA29963@redhat.com> <20190606140814.GA13440@redhat.com> <87k1dxaxcl.fsf_-_@xmission.com> Date: Fri, 07 Jun 2019 16:43:21 -0500 In-Reply-To: <87k1dxaxcl.fsf_-_@xmission.com> (Eric W. Biederman's message of "Fri, 07 Jun 2019 16:39:54 -0500") Message-ID: <87wohx9ime.fsf_-_@xmission.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.1 (gnu/linux) MIME-Version: 1.0 X-XM-SPF: eid=1hZMe5-00007T-Gx;;;mid=<87wohx9ime.fsf_-_@xmission.com>;;;hst=in01.mta.xmission.com;;;ip=72.206.97.68;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX18P0VJzgd3V/iTMGLHkzGDAaMXjRN+/OPE= X-SA-Exim-Connect-IP: 72.206.97.68 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: [RFC PATCH 4/5] signal: Remove saved_sigmask X-SA-Exim-Version: 4.2.1 (built Thu, 05 May 2016 13:38:54 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP We have real_sigmask that serves the same purpose and is always kept uptodate. Remove a field from the task structure and a conditional from the signal delivery code by removing this field. Signed-off-by: "Eric W. Biederman" --- include/linux/sched.h | 2 -- include/linux/sched/signal.h | 9 +++------ kernel/ptrace.c | 12 ++---------- kernel/signal.c | 2 -- 4 files changed, 5 insertions(+), 20 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 11837410690f..520efbd355be 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -864,8 +864,6 @@ struct task_struct { struct sighand_struct *sighand; sigset_t blocked; sigset_t real_blocked; - /* Restored if set_restore_sigmask() was used: */ - sigset_t saved_sigmask; struct sigpending pending; unsigned long sas_ss_sp; size_t sas_ss_size; diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index 97f6a6a35a81..78678de45278 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -407,7 +407,7 @@ void task_join_group_stop(struct task_struct *task); */ /** - * set_restore_sigmask() - make sure saved_sigmask processing gets done + * set_restore_sigmask() - make sure real_sigmask processing gets done * * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code * will run before returning to user mode, to process the flag. For @@ -479,7 +479,7 @@ static inline bool test_and_clear_restore_sigmask(void) static inline void restore_saved_sigmask(void) { if (test_and_clear_restore_sigmask()) - __set_current_blocked(¤t->saved_sigmask); + __set_current_blocked(¤t->real_blocked); } extern int set_user_sigmask(const sigset_t __user *umask, size_t sigsetsize); @@ -494,10 +494,7 @@ static inline void restore_saved_sigmask_unless(bool interrupted) static inline sigset_t *sigmask_to_save(void) { - sigset_t *res = ¤t->blocked; - if (unlikely(test_restore_sigmask())) - res = ¤t->saved_sigmask; - return res; + return ¤t->real_blocked; } static inline int kill_cad_pid(int sig, int priv) diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 6507d700d70f..5ed6126e1cc5 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -925,26 +925,18 @@ int ptrace_request(struct task_struct *child, long request, ret = ptrace_setsiginfo(child, &siginfo); break; - case PTRACE_GETSIGMASK: { - sigset_t *mask; - + case PTRACE_GETSIGMASK: if (addr != sizeof(sigset_t)) { ret = -EINVAL; break; } - if (test_tsk_restore_sigmask(child)) - mask = &child->saved_sigmask; - else - mask = &child->blocked; - - if (copy_to_user(datavp, mask, sizeof(sigset_t))) + if (copy_to_user(datavp, &child->real_blocked, sizeof(sigset_t))) ret = -EFAULT; else ret = 0; break; - } case PTRACE_SETSIGMASK: { sigset_t new_set; diff --git a/kernel/signal.c b/kernel/signal.c index fcd84f4a93c9..c37d4f209699 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2941,8 +2941,6 @@ EXPORT_SYMBOL(sigprocmask); static int set_sigmask(sigset_t *newset) { set_restore_sigmask(); - current->saved_sigmask = current->blocked; - sigdelsetmask(newset, sigmask(SIGKILL) | sigmask(SIGSTOP)); __set_current_blocked(newset);