From: Christian Brauner <brauner@kernel.org>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org,
Linus Torvalds <torvalds@linux-foundation.org>,
Jan Kara <jack@suse.cz>, Kazuma Kondo <kazuma-kondo@nec.com>
Subject: Re: [PATCH 5/5] fs: allow clone_private_mount() for a path on real rootfs
Date: Wed, 4 Jun 2025 09:40:28 +0200 [thread overview]
Message-ID: <20250604-vorrang-wandmalerei-60d109f72d4c@brauner> (raw)
In-Reply-To: <20250603232011.GE145532@ZenIV>
On Wed, Jun 04, 2025 at 12:20:11AM +0100, Al Viro wrote:
> From: =?UTF-8?q?KONDO=20KAZUMA=28=E8=BF=91=E8=97=A4=E3=80=80=E5=92=8C?=
> =?UTF-8?q?=E7=9C=9F=29?= <kazuma-kondo@nec.com>
>
> Mounting overlayfs with a directory on real rootfs (initramfs)
> as upperdir has failed with following message since commit
> db04662e2f4f ("fs: allow detached mounts in clone_private_mount()").
>
> [ 4.080134] overlayfs: failed to clone upperpath
>
> Overlayfs mount uses clone_private_mount() to create internal mount
> for the underlying layers.
>
> The commit made clone_private_mount() reject real rootfs because
> it does not have a parent mount and is in the initial mount namespace,
> that is not an anonymous mount namespace.
>
> This issue can be fixed by modifying the permission check
> of clone_private_mount() following [1].
>
> Fixes: db04662e2f4f ("fs: allow detached mounts in clone_private_mount()")
> Link: https://lore.kernel.org/all/20250514190252.GQ2023217@ZenIV/ [1]
> Link: https://lore.kernel.org/all/20250506194849.GT2023217@ZenIV/
> Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
> Signed-off-by: Kazuma Kondo <kazuma-kondo@nec.com>
> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> ---
Reviewed-by: Christian Brauner <brauner@kernel.org>
prev parent reply other threads:[~2025-06-04 7:40 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-06-03 23:15 [PATCHES][CFR] vfs fixes Al Viro
2025-06-03 23:16 ` [PATCH 1/5] fs/fhandle.c: fix a race in call of has_locked_children() Al Viro
2025-06-04 7:37 ` Christian Brauner
2025-06-04 11:57 ` Jeff Layton
2025-06-03 23:17 ` [PATCH 2/5] path_overmount(): avoid false negatives Al Viro
2025-06-04 7:38 ` Christian Brauner
2025-06-03 23:18 ` [PATCH 3/5] finish_automount(): don't leak MNT_LOCKED from parent to child Al Viro
2025-06-04 7:39 ` Christian Brauner
2025-06-03 23:19 ` [PATCH 4/5] fix propagation graph breakage by MOVE_MOUNT_SET_GROUP move_mount(2) Al Viro
2025-06-04 7:39 ` Christian Brauner
2025-06-03 23:20 ` [PATCH 5/5] fs: allow clone_private_mount() for a path on real rootfs Al Viro
2025-06-04 7:40 ` Christian Brauner [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=20250604-vorrang-wandmalerei-60d109f72d4c@brauner \
--to=brauner@kernel.org \
--cc=jack@suse.cz \
--cc=kazuma-kondo@nec.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
--cc=viro@zeniv.linux.org.uk \
/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