lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Thu, 6 Jul 2023 21:02:36 +0000
From:   Seth Arnold <seth.arnold@...onical.com>
To:     Jeff Layton <jlayton@...nel.org>
Cc:     Damien Le Moal <dlemoal@...nel.org>, jk@...abs.org, arnd@...db.de,
        mpe@...erman.id.au, npiggin@...il.com, christophe.leroy@...roup.eu,
        hca@...ux.ibm.com, gor@...ux.ibm.com, agordeev@...ux.ibm.com,
        borntraeger@...ux.ibm.com, svens@...ux.ibm.com,
        gregkh@...uxfoundation.org, arve@...roid.com, tkjos@...roid.com,
        maco@...roid.com, joel@...lfernandes.org, brauner@...nel.org,
        cmllamas@...gle.com, surenb@...gle.com,
        dennis.dalessandro@...nelisnetworks.com, jgg@...pe.ca,
        leon@...nel.org, bwarrum@...ux.ibm.com, rituagar@...ux.ibm.com,
        ericvh@...nel.org, lucho@...kov.net, asmadeus@...ewreck.org,
        linux_oss@...debyte.com, dsterba@...e.com, dhowells@...hat.com,
        marc.dionne@...istor.com, viro@...iv.linux.org.uk,
        raven@...maw.net, luisbg@...nel.org, salah.triki@...il.com,
        aivazian.tigran@...il.com, ebiederm@...ssion.com,
        keescook@...omium.org, clm@...com, josef@...icpanda.com,
        xiubli@...hat.com, idryomov@...il.com, jaharkes@...cmu.edu,
        coda@...cmu.edu, jlbec@...lplan.org, hch@....de, nico@...xnic.net,
        rafael@...nel.org, code@...icks.com, ardb@...nel.org,
        xiang@...nel.org, chao@...nel.org, huyue2@...lpad.com,
        jefflexu@...ux.alibaba.com, linkinjeon@...nel.org,
        sj1557.seo@...sung.com, jack@...e.com, tytso@....edu,
        adilger.kernel@...ger.ca, jaegeuk@...nel.org,
        hirofumi@...l.parknet.co.jp, miklos@...redi.hu,
        rpeterso@...hat.com, agruenba@...hat.com, richard@....at,
        anton.ivanov@...bridgegreys.com, johannes@...solutions.net,
        mikulas@...ax.karlin.mff.cuni.cz, mike.kravetz@...cle.com,
        muchun.song@...ux.dev, dwmw2@...radead.org, shaggy@...nel.org,
        tj@...nel.org, trond.myklebust@...merspace.com, anna@...nel.org,
        chuck.lever@...cle.com, neilb@...e.de, kolga@...app.com,
        Dai.Ngo@...cle.com, tom@...pey.com, konishi.ryusuke@...il.com,
        anton@...era.com, almaz.alexandrovich@...agon-software.com,
        mark@...heh.com, joseph.qi@...ux.alibaba.com, me@...copeland.com,
        hubcap@...ibond.com, martin@...ibond.com, amir73il@...il.com,
        mcgrof@...nel.org, yzaikin@...gle.com, tony.luck@...el.com,
        gpiccoli@...lia.com, al@...rsen.net, sfrench@...ba.org,
        pc@...guebit.com, lsahlber@...hat.com, sprasad@...rosoft.com,
        senozhatsky@...omium.org, phillip@...ashfs.org.uk,
        rostedt@...dmis.org, mhiramat@...nel.org, dushistov@...l.ru,
        hdegoede@...hat.com, djwong@...nel.org, naohiro.aota@....com,
        jth@...nel.org, ast@...nel.org, daniel@...earbox.net,
        andrii@...nel.org, martin.lau@...ux.dev, song@...nel.org,
        yhs@...com, john.fastabend@...il.com, kpsingh@...nel.org,
        sdf@...gle.com, haoluo@...gle.com, jolsa@...nel.org,
        hughd@...gle.com, akpm@...ux-foundation.org, davem@...emloft.net,
        edumazet@...gle.com, kuba@...nel.org, pabeni@...hat.com,
        john.johansen@...onical.com, paul@...l-moore.com,
        jmorris@...ei.org, serge@...lyn.com,
        stephen.smalley.work@...il.com, eparis@...isplace.org,
        jgross@...e.com, stern@...land.harvard.edu, lrh2000@....edu.cn,
        sebastian.reichel@...labora.com, wsa+renesas@...g-engineering.com,
        quic_ugoswami@...cinc.com, quic_linyyuan@...cinc.com,
        john@...ping.me.uk, error27@...il.com, quic_uaggarwa@...cinc.com,
        hayama@...eo.co.jp, jomajm@...il.com, axboe@...nel.dk,
        dhavale@...gle.com, dchinner@...hat.com, hannes@...xchg.org,
        zhangpeng362@...wei.com, slava@...eyko.com, gargaditya08@...e.com,
        penguin-kernel@...ove.SAKURA.ne.jp, yifeliu@...stonybrook.edu,
        madkar@...stonybrook.edu, ezk@...stonybrook.edu,
        yuzhe@...china.com, willy@...radead.org, okanatov@...il.com,
        jeffxu@...omium.org, linux@...blig.org, mirimmad17@...il.com,
        yijiangshan@...inos.cn, yang.yang29@....com.cn,
        xu.xin16@....com.cn, chengzhihao1@...wei.com, shr@...kernel.io,
        Liam.Howlett@...cle.com, adobriyan@...il.com,
        chi.minghao@....com.cn, roberto.sassu@...wei.com,
        linuszeng@...cent.com, bvanassche@....org, zohar@...ux.ibm.com,
        yi.zhang@...wei.com, trix@...hat.com, fmdefrancesco@...il.com,
        ebiggers@...gle.com, princekumarmaurya06@...il.com,
        chenzhongjin@...wei.com, riel@...riel.com,
        shaozhengchao@...wei.com, jingyuwang_vip@....com,
        linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org,
        linux-s390@...r.kernel.org, linux-rdma@...r.kernel.org,
        linux-usb@...r.kernel.org, v9fs@...ts.linux.dev,
        linux-fsdevel@...r.kernel.org, linux-afs@...ts.infradead.org,
        autofs@...r.kernel.org, linux-mm@...ck.org,
        linux-btrfs@...r.kernel.org, ceph-devel@...r.kernel.org,
        codalist@...a.cs.cmu.edu, ecryptfs@...r.kernel.org,
        linux-efi@...r.kernel.org, linux-erofs@...ts.ozlabs.org,
        linux-ext4@...r.kernel.org, linux-f2fs-devel@...ts.sourceforge.net,
        cluster-devel@...hat.com, linux-um@...ts.infradead.org,
        linux-mtd@...ts.infradead.org,
        jfs-discussion@...ts.sourceforge.net, linux-nfs@...r.kernel.org,
        linux-nilfs@...r.kernel.org, linux-ntfs-dev@...ts.sourceforge.net,
        ntfs3@...ts.linux.dev, ocfs2-devel@...ts.linux.dev,
        linux-karma-devel@...ts.sourceforge.net, devel@...ts.orangefs.org,
        linux-unionfs@...r.kernel.org, linux-hardening@...r.kernel.org,
        reiserfs-devel@...r.kernel.org, linux-cifs@...r.kernel.org,
        samba-technical@...ts.samba.org,
        linux-trace-kernel@...r.kernel.org, linux-xfs@...r.kernel.org,
        bpf@...r.kernel.org, netdev@...r.kernel.org,
        apparmor@...ts.ubuntu.com, linux-security-module@...r.kernel.org,
        selinux@...r.kernel.org
Subject: Re: [apparmor] [PATCH v2 08/92] fs: new helper:
 simple_rename_timestamp

On Wed, Jul 05, 2023 at 08:04:41PM -0400, Jeff Layton wrote:
> 
> I don't believe it's an issue. I've seen nothing in the POSIX spec that
> mandates that timestamp updates to different inodes involved in an
> operation be set to the _same_ value. It just says they must be updated.
> 
> It's also hard to believe that any software would depend on this either,
> given that it's very inconsistent across filesystems today. AFAICT, this
> was mostly done in the past just as a matter of convenience.

I've seen this assumption in several programs:

mutt buffy.c
https://sources.debian.org/src/mutt/2.2.9-1/buffy.c/?hl=625#L625

  if (mailbox->newly_created &&
      (sb->st_ctime != sb->st_mtime || sb->st_ctime != sb->st_atime))
    mailbox->newly_created = 0;


neomutt mbox/mbox.c
https://sources.debian.org/src/neomutt/20220429+dfsg1-4.1/mbox/mbox.c/?hl=1820#L1820

  if (m->newly_created && ((st.st_ctime != st.st_mtime) || (st.st_ctime != st.st_atime)))
    m->newly_created = false;


screen logfile.c
https://sources.debian.org/src/screen/4.9.0-4/logfile.c/?hl=130#L130

  if ((!s->st_dev && !s->st_ino) ||             /* stat failed, that's new! */
      !s->st_nlink ||                           /* red alert: file unlinked */
      (s->st_size < o.st_size) ||               /*           file truncated */
      (s->st_mtime != o.st_mtime) ||            /*            file modified */
      ((s->st_ctime != o.st_ctime) &&           /*     file changed (moved) */
       !(s->st_mtime == s->st_ctime &&          /*  and it was not a change */
         o.st_ctime < s->st_ctime)))            /* due to delayed nfs write */
  {

nemo libnemo-private/nemo-vfs-file.c
https://sources.debian.org/src/nemo/5.6.5-1/libnemo-private/nemo-vfs-file.c/?hl=344#L344

		/* mtime is when the contents changed; ctime is when the
		 * contents or the permissions (inc. owner/group) changed.
		 * So we can only know when the permissions changed if mtime
		 * and ctime are different.
		 */
		if (file->details->mtime == file->details->ctime) {
			return FALSE;
		}


While looking for more examples, I found a perl test that seems to suggest
that at least Solaris, AFS, AmigaOS, DragonFly BSD do as you suggest:
https://sources.debian.org/src/perl/5.36.0-7/t/op/stat.t/?hl=158#L140


Thanks

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ