From: Greg KH <gregkh@linuxfoundation.org>
To: Stan Hu <stanhu@gmail.com>
Cc: stable@vger.kernel.org, Miklos Szeredi <mszeredi@redhat.com>
Subject: Re: Request for cherry-picking overlayfs fixes in 5.10.x stable
Date: Fri, 3 Dec 2021 11:31:04 +0100 [thread overview]
Message-ID: <Yanx6KobwiQoBQfU@kroah.com> (raw)
In-Reply-To: <CAMBWrQ=1MKxnMT_6Jnqp_xxr7psVywPBJc6p1qCy9ENY8RF2Qw@mail.gmail.com>
On Thu, Dec 02, 2021 at 04:29:34PM -0800, Stan Hu wrote:
> A number of users have reported that under certain conditions using
> the overlay filesystem, copy_file_range() can unexpectedly create a
> 0-byte file. [0]
>
> This bug can cause significant problems because applications that copy
> files expect the target file to match the source immediately after the
> copy. After upgrading from Linux 5.4 to Linux 5.10, our Docker-based
> CI tests started failing due to this bug, since Ruby's IO.copy_stream
> uses this system call. We have worked around the problem by touching
> the target file before using it, but this shouldn't be necessary.
> Other projects, such as Rust, have added similar workarounds. [1]
>
> As discussed in the linux-fsdevel mailing list [2], the bug appears to
> be present in Linux 5.6 to 5.10, but not in Linux 5.11. We should be
> able to cherry-pick the following upstream patches to fix this. Could
> you cherry-pick them to 5.10.x stable? I've confirmed that these
> patches, applied from top to bottom to that branch, pass the
> reproduction test [3]:
>
> 82a763e61e2b601309d696d4fa514c77d64ee1be
> 9b91b6b019fda817eb52f728eb9c79b3579760bc
>
> The diffstat:
>
> fs/overlayfs/file.c | 59
> +++++++++++++++++++++++++++++++----------------------------
> 1 file changed, 31 insertions(+), 28 deletions(-)
>
> Note that these patches do not pick cleanly into 5.6.x - 5.9.x stable.
>
> [0] https://github.com/docker/for-linux/issues/1015
> [1] https://github.com/rust-lang/rust/blob/342db70ae4ecc3cd17e4fa6497f0a8d9534ccfeb/library/std/src/sys/unix/kernel_copy.rs#L565-L569
> [2] https://marc.info/?l=linux-fsdevel&m=163847383311699&w=2
> [3] https://github.com/docker/for-linux/issues/1015#issuecomment-841915668
Now queued up, thanks,
greg k-h
prev parent reply other threads:[~2021-12-03 10:31 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-03 0:29 Request for cherry-picking overlayfs fixes in 5.10.x stable Stan Hu
2021-12-03 10:31 ` Greg KH [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=Yanx6KobwiQoBQfU@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=mszeredi@redhat.com \
--cc=stable@vger.kernel.org \
--cc=stanhu@gmail.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.