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=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 32EE1C32751 for ; Wed, 31 Jul 2019 15:33:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F0E9B206A3 for ; Wed, 31 Jul 2019 15:33:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="LAz5/a69" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728157AbfGaPdu (ORCPT ); Wed, 31 Jul 2019 11:33:50 -0400 Received: from mail-io1-f68.google.com ([209.85.166.68]:36533 "EHLO mail-io1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725209AbfGaPdu (ORCPT ); Wed, 31 Jul 2019 11:33:50 -0400 Received: by mail-io1-f68.google.com with SMTP id o9so33606864iom.3; Wed, 31 Jul 2019 08:33:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=yI0JpspD1113sUBtAqLZbFVFbLJqu1gr4xDjLSMreiw=; b=LAz5/a69YdR7Pt36ZVsGmVGHpGp+4qFpAIYuoITCJqrz5Gd8B+Ylo1NbHJTTCjmxbX thvsIlzvZ0kbcB7WehCIGIUZnNEJiBxwjbVFOIrws/AU3swVmolYIDA1t8pzCjxFOUGN EVChaEPYrK2rJ2O2U9fyhgylfagpoyXUogqgoYlDIR5bh4KugnehZ6GcC14uaLXH9FKG 2P50hqW7flLwOgVQ7DtjCOryeL83sgbY/es35/f4Sd3q9Wdp5Yykz8mXVnM5KXOBrocE 2o7oC4kBDg6UFRswY3tLoC/0HxGKpyf4Xp/Xf4QRT1yUyixALFsf6XlbEDtSiK1YPVoP ry5g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=yI0JpspD1113sUBtAqLZbFVFbLJqu1gr4xDjLSMreiw=; b=hhtJJRtrp1gseDLplq8HAarBiv9Xgp2fQKvoxpLsK9lK/ImyNYEXWGdWcSRkAZ0AG/ QJLADHImsSnswNndZvpikn+faIuJHigOllGqeVtOVSh1G2tSXSyaxHQWxizNQhXOFGnp 59nxMgKdDGpgBGE8E/09XfYBZTvZtQT58wkmglms9bxdDzn2cboLuKRatL4iP92kTC59 s5LYuKvv13YeT8xczwXhQuxcJQg6FYSw6DMKbyorzb50/tdCCpvSwiL5DezvOUIU8vrV 8Tg3osuBi6W5AvkTABvjU4iu1NSsmpvxYowAQg2oJn52YmHOCUSN+U0Qq3pxj6ysA2Nw c/uA== X-Gm-Message-State: APjAAAU1Pk5Tus7i5mA4OaNWOaZ5TsuKN7O0foze/4u4fhScQ/3pfhDk gmchb2g1WEt6tXS1xriUONADx+e+4L0eF9QPtTM= X-Google-Smtp-Source: APXvYqyyEUfB7Inu5/gImzGyMyc1RdpNROfupfk2bU9j14soRxHbI/8kSJJb6tSun7W2m0osy6EPjpO+f2kqvHjEuc8= X-Received: by 2002:a6b:ed09:: with SMTP id n9mr1036752iog.153.1564587229296; Wed, 31 Jul 2019 08:33:49 -0700 (PDT) MIME-Version: 1.0 References: <20190730014924.2193-1-deepa.kernel@gmail.com> <20190730014924.2193-6-deepa.kernel@gmail.com> <20190731151452.GA7077@magnolia> In-Reply-To: <20190731151452.GA7077@magnolia> From: Deepa Dinamani Date: Wed, 31 Jul 2019 08:33:37 -0700 Message-ID: Subject: Re: [PATCH 05/20] utimes: Clamp the timestamps before update To: "Darrick J. Wong" Cc: Alexander Viro , Linux Kernel Mailing List , Linux FS-devel Mailing List , Arnd Bergmann , y2038 Mailman List Content-Type: text/plain; charset="UTF-8" Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Wed, Jul 31, 2019 at 8:15 AM Darrick J. Wong wrote: > > On Mon, Jul 29, 2019 at 06:49:09PM -0700, Deepa Dinamani wrote: > > POSIX is ambiguous on the behavior of timestamps for > > futimens, utimensat and utimes. Whether to return an > > error or silently clamp a timestamp beyond the range > > supported by the underlying filesystems is not clear. > > > > POSIX.1 section for futimens, utimensat and utimes says: > > (http://pubs.opengroup.org/onlinepubs/9699919799/functions/futimens.html) > > > > The file's relevant timestamp shall be set to the greatest > > value supported by the file system that is not greater > > than the specified time. > > > > If the tv_nsec field of a timespec structure has the special > > value UTIME_NOW, the file's relevant timestamp shall be set > > to the greatest value supported by the file system that is > > not greater than the current time. > > > > [EINVAL] > > A new file timestamp would be a value whose tv_sec > > component is not a value supported by the file system. > > > > The patch chooses to clamp the timestamps according to the > > filesystem timestamp ranges and does not return an error. > > This is in line with the behavior of utime syscall also > > since the POSIX page(http://pubs.opengroup.org/onlinepubs/009695399/functions/utime.html) > > for utime does not mention returning an error or clamping like above. > > > > Same for utimes http://pubs.opengroup.org/onlinepubs/009695399/functions/utimes.html > > > > Signed-off-by: Deepa Dinamani > > --- > > fs/utimes.c | 17 +++++++++++++---- > > 1 file changed, 13 insertions(+), 4 deletions(-) > > > > diff --git a/fs/utimes.c b/fs/utimes.c > > index 350c9c16ace1..4c1a2ce90bbc 100644 > > --- a/fs/utimes.c > > +++ b/fs/utimes.c > > @@ -21,6 +21,7 @@ static int utimes_common(const struct path *path, struct timespec64 *times) > > int error; > > struct iattr newattrs; > > struct inode *inode = path->dentry->d_inode; > > + struct super_block *sb = inode->i_sb; > > struct inode *delegated_inode = NULL; > > > > error = mnt_want_write(path->mnt); > > @@ -36,16 +37,24 @@ static int utimes_common(const struct path *path, struct timespec64 *times) > > if (times[0].tv_nsec == UTIME_OMIT) > > newattrs.ia_valid &= ~ATTR_ATIME; > > else if (times[0].tv_nsec != UTIME_NOW) { > > - newattrs.ia_atime.tv_sec = times[0].tv_sec; > > - newattrs.ia_atime.tv_nsec = times[0].tv_nsec; > > + newattrs.ia_atime.tv_sec = > > + clamp(times[0].tv_sec, sb->s_time_min, sb->s_time_max); > > + if (times[0].tv_sec == sb->s_time_max || times[0].tv_sec == sb->s_time_min) > > + newattrs.ia_atime.tv_nsec = 0; > > + else > > + newattrs.ia_atime.tv_nsec = times[0].tv_nsec; > > newattrs.ia_valid |= ATTR_ATIME_SET; > > } > > > > if (times[1].tv_nsec == UTIME_OMIT) > > newattrs.ia_valid &= ~ATTR_MTIME; > > else if (times[1].tv_nsec != UTIME_NOW) { > > - newattrs.ia_mtime.tv_sec = times[1].tv_sec; > > - newattrs.ia_mtime.tv_nsec = times[1].tv_nsec; > > + newattrs.ia_mtime.tv_sec = > > + clamp(times[1].tv_sec, sb->s_time_min, sb->s_time_max); > > + if (times[1].tv_sec >= sb->s_time_max || times[1].tv_sec == sb->s_time_min) > > Line length. > > Also, didn't you just introduce a function to clamp tv_sec and fix > granularity? Why not just use it here? I think this is the third time > I've seen this open-coded logic. Yes, we can use that now. Earlier we were not setting the tv_nsec to 0 in timestamp_truncate() which is why this was opencoded here. I will make the change to include this. Thanks, Deepa