From: Ming Lei <ming.lei@redhat.com>
To: Caleb Sander Mateos <csander@purestorage.com>
Cc: Jens Axboe <axboe@kernel.dk>,
Govindarajulu Varadarajan <govind.varadar@gmail.com>,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/4] ublk: don't write to struct ublksrv_ctrl_cmd
Date: Fri, 30 Jan 2026 23:48:38 +0800 [thread overview]
Message-ID: <aXzS1iOjZAVEcZ8k@fedora> (raw)
In-Reply-To: <20260129224618.975401-3-csander@purestorage.com>
On Thu, Jan 29, 2026 at 03:46:15PM -0700, Caleb Sander Mateos wrote:
> ublk_ctrl_uring_cmd_permission() writes to struct ublksrv_ctrl_cmd's
> addr and len fields, which is racy because ublksrv_ctrl_cmd is part of
> the io_uring_sqe, which may lie in userspace-mapped memory. Store the
> values of addr in len in local variables instead to avoid the race.
>
> Fixes: 87213b0d847c ("ublk: allow non-blocking ctrl cmds in IO_URING_F_NONBLOCK issue")
> Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
The simpler approach is to define local `header` variable and copy data to
it.
Given it is introduced in v6.19-rc1, backport should be easy, so this patch
looks fine:
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Thanks,
Ming
next prev parent reply other threads:[~2026-01-30 15:49 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-29 22:46 [PATCH 0/4] ublk: fix struct ublksrv_ctrl_cmd accesses Caleb Sander Mateos
2026-01-29 22:46 ` [PATCH 1/4] ublk: Validate SQE128 flag before accessing the cmd Caleb Sander Mateos
2026-01-30 8:03 ` Ming Lei
2026-01-29 22:46 ` [PATCH 2/4] ublk: don't write to struct ublksrv_ctrl_cmd Caleb Sander Mateos
2026-01-30 15:48 ` Ming Lei [this message]
2026-01-30 16:05 ` Ming Lei
2026-01-29 22:46 ` [PATCH 3/4] ublk: use READ_ONCE() to read " Caleb Sander Mateos
2026-01-30 15:56 ` Ming Lei
2026-01-29 22:46 ` [PATCH 4/4] ublk: drop ublk_ctrl_{start,end}_recovery() header argument Caleb Sander Mateos
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=aXzS1iOjZAVEcZ8k@fedora \
--to=ming.lei@redhat.com \
--cc=axboe@kernel.dk \
--cc=csander@purestorage.com \
--cc=govind.varadar@gmail.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/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