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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 D7CABC3815B for ; Mon, 20 Apr 2020 12:45:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B737F21473 for ; Mon, 20 Apr 2020 12:45:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587386711; bh=3U4MOA2zSjanbkoh2i0PBmMVJ0JOxoR9ZqVWiBu1pGM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jLeAb4LNw4Eh55zgyQ2oEctAN6EZVoaH9ihvxJEKy/CP9OLBy0Ee97NwXWa4qkgJ0 bYJXBavFh2hIMo+nWbw+uTra1ofCX11hZ7pzr9I5+PmhnE+As3TupDivtWg81oBtL4 zX0CcB68c2oVZdWpQ1i1KEzTicN86UL7BkMUzRI4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728672AbgDTMpL (ORCPT ); Mon, 20 Apr 2020 08:45:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:39422 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728638AbgDTMpJ (ORCPT ); Mon, 20 Apr 2020 08:45:09 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 875E120747; Mon, 20 Apr 2020 12:45:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587386709; bh=3U4MOA2zSjanbkoh2i0PBmMVJ0JOxoR9ZqVWiBu1pGM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g2y2J8XF4e9oJjMtKXGfcQqvmdY34H4aIAufKZ+48guUrCGpJNuyzelnTy72mjCuV +p0BYm6luH1c25+xEqlQr5BtZ1CWeENisiB86pFk/+JMCp2er5qvxOHHrSDpxlZMIv H70bMEjYCM4BEfU+zYYi/Kopuszo90PF6nHYIz8U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Kerrisk , Andrei Vagin , Thomas Gleixner , Andrew Morton , "Eric W. Biederman" , Dmitry Safonov <0x7f454c46@gmail.com> Subject: [PATCH 5.6 67/71] proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets Date: Mon, 20 Apr 2020 14:39:21 +0200 Message-Id: <20200420121522.296713087@linuxfoundation.org> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20200420121508.491252919@linuxfoundation.org> References: <20200420121508.491252919@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Andrei Vagin commit 94d440d618467806009c8edc70b094d64e12ee5a upstream. 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 Signed-off-by: Greg Kroah-Hartman --- fs/proc/base.c | 14 +++++++++++++- kernel/time/namespace.c | 15 ++++++++++++++- 2 files changed, 27 insertions(+), 2 deletions(-) --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1573,6 +1573,7 @@ static ssize_t timens_offsets_write(stru 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(stru 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) --- a/kernel/time/namespace.c +++ b/kernel/time/namespace.c @@ -337,7 +337,20 @@ static struct user_namespace *timens_own 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)