From patchwork Thu Apr 16 10:15:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: thermal-bot for Julien Panis X-Patchwork-Id: 227950 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=-11.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 00D72C2BB85 for ; Thu, 16 Apr 2020 10:17:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D121B206B9 for ; Thu, 16 Apr 2020 10:17:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2441518AbgDPKQR (ORCPT ); Thu, 16 Apr 2020 06:16:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53890 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2441482AbgDPKPo (ORCPT ); Thu, 16 Apr 2020 06:15:44 -0400 Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7CD73C061A0C; Thu, 16 Apr 2020 03:15:43 -0700 (PDT) Received: from [5.158.153.53] (helo=tip-bot2.lab.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jP1Ya-00046E-CQ; Thu, 16 Apr 2020 12:15:40 +0200 Received: from [127.0.1.1] (localhost [IPv6:::1]) by tip-bot2.lab.linutronix.de (Postfix) with ESMTP id A873C1C001F; Thu, 16 Apr 2020 12:15:39 +0200 (CEST) Date: Thu, 16 Apr 2020 10:15:39 -0000 From: "tip-bot2 for Andrei Vagin" Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: timers/urgent] proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets Cc: Michael Kerrisk , Andrei Vagin , Thomas Gleixner , Andrew Morton , "Eric W. Biederman" , Dmitry Safonov <0x7f454c46@gmail.com>, stable@vger.kernel.org, x86 , LKML In-Reply-To: <20200411154031.642557-1-avagin@gmail.com> References: <20200411154031.642557-1-avagin@gmail.com> MIME-Version: 1.0 Message-ID: <158703213918.28353.5534603422697683760.tip-bot2@tip-bot2> X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1, SHORTCIRCUIT=-0.0001 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The following commit has been merged into the timers/urgent branch of tip: Commit-ID: 94d440d618467806009c8edc70b094d64e12ee5a Gitweb: https://git.kernel.org/tip/94d440d618467806009c8edc70b094d64e12ee5a Author: Andrei Vagin AuthorDate: Sat, 11 Apr 2020 08:40:31 -07:00 Committer: Thomas Gleixner CommitterDate: Thu, 16 Apr 2020 12:10:54 +02:00 proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets Michael Kerrisk suggested to replace numeric clock IDs with symbolic names. Now the content of these files looks like this: $ cat /proc/774/timens_offsets monotonic 864000 0 boottime 1728000 0 For setting offsets, both representations of clocks (numeric and symbolic) can be used. As for compatibility, it is acceptable to change things as long as userspace doesn't care. The format of timens_offsets files is very new and there are no userspace tools yet which rely on this format. But three projects crun, util-linux and criu rely on the interface of setting time offsets and this is why it's required to continue supporting the numeric clock IDs on write. Fixes: 04a8682a71be ("fs/proc: Introduce /proc/pid/timens_offsets") Suggested-by: Michael Kerrisk Signed-off-by: Andrei Vagin Signed-off-by: Thomas Gleixner Tested-by: Michael Kerrisk Acked-by: Michael Kerrisk Cc: Andrew Morton Cc: Eric W. Biederman Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20200411154031.642557-1-avagin@gmail.com --- fs/proc/base.c | 14 +++++++++++++- kernel/time/namespace.c | 15 ++++++++++++++- 2 files changed, 27 insertions(+), 2 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 6042b64..572898d 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1573,6 +1573,7 @@ static ssize_t timens_offsets_write(struct file *file, const char __user *buf, noffsets = 0; for (pos = kbuf; pos; pos = next_line) { struct proc_timens_offset *off = &offsets[noffsets]; + char clock[10]; int err; /* Find the end of line and ensure we don't look past it */ @@ -1584,10 +1585,21 @@ static ssize_t timens_offsets_write(struct file *file, const char __user *buf, next_line = NULL; } - err = sscanf(pos, "%u %lld %lu", &off->clockid, + err = sscanf(pos, "%9s %lld %lu", clock, &off->val.tv_sec, &off->val.tv_nsec); if (err != 3 || off->val.tv_nsec >= NSEC_PER_SEC) goto out; + + clock[sizeof(clock) - 1] = 0; + if (strcmp(clock, "monotonic") == 0 || + strcmp(clock, __stringify(CLOCK_MONOTONIC)) == 0) + off->clockid = CLOCK_MONOTONIC; + else if (strcmp(clock, "boottime") == 0 || + strcmp(clock, __stringify(CLOCK_BOOTTIME)) == 0) + off->clockid = CLOCK_BOOTTIME; + else + goto out; + noffsets++; if (noffsets == ARRAY_SIZE(offsets)) { if (next_line) diff --git a/kernel/time/namespace.c b/kernel/time/namespace.c index 3b30288..53bce34 100644 --- a/kernel/time/namespace.c +++ b/kernel/time/namespace.c @@ -338,7 +338,20 @@ static struct user_namespace *timens_owner(struct ns_common *ns) static void show_offset(struct seq_file *m, int clockid, struct timespec64 *ts) { - seq_printf(m, "%d %lld %ld\n", clockid, ts->tv_sec, ts->tv_nsec); + char *clock; + + switch (clockid) { + case CLOCK_BOOTTIME: + clock = "boottime"; + break; + case CLOCK_MONOTONIC: + clock = "monotonic"; + break; + default: + clock = "unknown"; + break; + } + seq_printf(m, "%-10s %10lld %9ld\n", clock, ts->tv_sec, ts->tv_nsec); } void proc_timens_show_offsets(struct task_struct *p, struct seq_file *m)