linux-ext4 - [Bug 200681] [inline_data] read() does not see what write() has just written through different FD in the same thread

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: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <bug-200681-13602-bX4cK8mhSo@https.bugzilla.kernel.org/>
Date:   Wed, 01 Aug 2018 15:21:59 +0000
From:   bugzilla-daemon@...zilla.kernel.org
To:     linux-ext4@...nel.org
Subject: [Bug 200681] [inline_data] read() does not see what write() has just
 written through different FD in the same thread

https://bugzilla.kernel.org/show_bug.cgi?id=200681

Theodore Tso (tytso@....edu) changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |tytso@....edu

--- Comment #3 from Theodore Tso (tytso@....edu) ---
So it's not reproducing for me using my standard test framework, kvm-xfstests:

https://github.com/tytso/xfstests-bld/blob/master/Documentation/kvm-quickstart.md

What I did:

Edited your reproducer program to use "./xyz" instead of "/mnt/xyz", compiled
it, and put the binary in /tmp/kvm-xfstests-tytso/repro. 
(/tmp/kvm-xfstests-$USER will get mounted using 9p by kvm-xfstests in the guest
OS as /vtmp.)

% kvm-xfstests shell
...
root@...-xfstests:~# mount /vtmp
root@...-xfstests:~# mke2fs -Fq -t ext4 -O inline_data -I 1024 /dev/vdc 
/dev/vdc contains a ext4 file system
        last mounted on /vdc on Wed Aug  1 11:09:56 2018
root@...-xfstests:~# mount /vdc
[  761.839810] EXT4-fs (vdc): mounted filesystem with ordered data mode. Opts:
(null)
root@...-xfstests:~# cd /vdc
root@...-xfstests:/vdc# /vtmp/repro
res1 = 17968 res2 = 48          first bytes of data are: 01 02 03...

If I have time I can try to repro it with your reproducer, but maybe you can
try using kvm-xfstests yourself?  I think you will find it is a much more
convenient system, and if ext4 users, developers, and bug reports all use the
same system it saves a lot of time --- otherwise there are many more of *you*
than there is of *me* and I don't scale that well unless I ask people to use
common tools and procedures.    (See https://thunk.org/gce-xfstests for an
introduction to kvm-xfstests and gce-xfstests.)

-- 
You are receiving this mail because:
You are watching the assignee of the bug.