From: Matthieu Baerts <matttbe@kernel.org>
To: Tao Cui <cuitao@kylinos.cn>, geliang@kernel.org
Cc: mptcp@lists.linux.dev
Subject: Re: [PATCH mptcp-next] mptcp: pm: add WARN_ON_ONCE guards on extra_subflows underflow
Date: Wed, 27 May 2026 21:40:48 +1000 [thread overview]
Message-ID: <4e5575e3-038b-43eb-9d63-9fcbd5116fcd@kernel.org> (raw)
In-Reply-To: <20260522085049.1896537-1-cuitao@kylinos.cn>
Hi Tao,
On 22/05/2026 18:50, Tao Cui wrote:
> extra_subflows is a u8 counter that can underflow if a decrement races
> with or precedes an increment. While the recently fixed userspace PM
> subflow creation path eliminated the primary cause, add defensive
> WARN_ON_ONCE guards at both decrement sites to catch any remaining edge
> cases rather than silently wrapping to 255.
Thank you for the patch:
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
New patches for t/upstream:
- abefe4ecdb46: mptcp: pm: add WARN_ON_ONCE guards on extra_subflows
underflow
- Results: c40ac68d9bc2..cde220b5fe28 (export)
Tests are now in progress:
- export:
https://github.com/multipath-tcp/mptcp_net-next/commit/02fc64d2cebb020984c74fb4950be7a46909b4d9/checks
Cheers,
Matt
--
Sponsored by the NGI0 Core fund.
prev parent reply other threads:[~2026-05-27 11:40 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-22 8:50 [PATCH mptcp-next] mptcp: pm: add WARN_ON_ONCE guards on extra_subflows underflow Tao Cui
2026-05-22 10:31 ` MPTCP CI
2026-05-27 11:40 ` Matthieu Baerts [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=4e5575e3-038b-43eb-9d63-9fcbd5116fcd@kernel.org \
--to=matttbe@kernel.org \
--cc=cuitao@kylinos.cn \
--cc=geliang@kernel.org \
--cc=mptcp@lists.linux.dev \
/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.