From: no-reply@sashiko.virtuozzo.com
To: devel@openvz.org, Konstantin Khorenko <khorenko@virtuozzo.com>
Subject: Re: [Devel] [PATCH vz10 v2] fs/kernfs, ve: pin the VE that created a kernfs instance
Date: Tue, 29 Sep 2026 16:54:50 +0000 [thread overview]
Message-ID: <010701a0ee1728f9-f1fb77d7-9c07-419d-86fe-967eaf94586f-000000@eu-central-1.amazonses.com> (raw)
In-Reply-To: <20260929-prep-kh-vstor-142552-kernfs-pin-ve-v2-1-0795e3aee679@virtuozzo.com>
> kernfs_get_tree() stores a bare get_exec_env() pointer in
> kernfs_super_info, and since commit 8d1abf587552 ("fs/kernfs, ve:
> hide entries from a VE without invalidating the dentry")
> kernfs_dop_revalidate() compares it against the caller's VE to decide
> between dropping the dentry and answering -ENOENT.
>
> Nothing backs that pointer with a reference: if the mount is pinned from
> outside - the host bind-mounted a Container's sysfs, or holds an fd
> inside it - the superblock outlives the Container, info->ve dangles, and
> a later Container whose ve_struct is allocated at the same address is
> mistaken for the creator of the instance. Its lookups then take the
> d_invalidate() path on the dead instance and detach the mounts placed on
> top of it.
>
> Take a css reference on the VE for the lifetime of the superblock, so
> [ ... ]
> Fixes: 8d1abf587552 ("fs/kernfs, ve: hide entries from a VE without invalidating the dentry")
> https://virtuozzo.atlassian.net/browse/VSTOR-142552
>
> Feature: kernfs: per-CT entries visibility and permissions configuration
> Signed-off-by: Konstantin Khorenko <khorenko@virtuozzo.com>
Sashiko has reviewed this patch and found no issues. It looks great!
--
Sashiko AI review · https://sashiko.dev/#/patchset/20260929-prep-kh-vstor-142552-kernfs-pin-ve-v2-1-0795e3aee679@virtuozzo.com?part=1
_______________________________________________
Devel mailing list
Devel@openvz.org
https://lists.openvz.org/mailman/listinfo/devel
prev parent reply other threads:[~2026-09-29 16:56 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-29 16:49 Konstantin Khorenko
2026-09-29 16:51 ` Konstantin Khorenko
2026-09-29 16:54 ` no-reply [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=010701a0ee1728f9-f1fb77d7-9c07-419d-86fe-967eaf94586f-000000@eu-central-1.amazonses.com \
--to=no-reply@sashiko.virtuozzo.com \
--cc=devel@openvz.org \
--cc=khorenko@virtuozzo.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox