Hi Greg,
On 26/02/2024 14:17, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
>
> The patch below does not apply to the 5.15-stable tree.
(...)
> Possible dependencies:
>
> a7cfe7766370 ("mptcp: fix data races on local_id")
> 84c531f54ad9 ("mptcp: userspace pm send RM_ADDR for ID 0")
> f1f26512a9bf ("mptcp: use plain bool instead of custom binary enum")
> 1e07938e29c5 ("net: mptcp: rename netlink handlers to mptcp_pm_nl_<blah>_{doit,dumpit}")
> 1d0507f46843 ("net: mptcp: convert netlink from small_ops to ops")
> fce68b03086f ("mptcp: add scheduled in mptcp_subflow_context")
> 1730b2b2c5a5 ("mptcp: add sched in mptcp_sock")
> 740ebe35bd3f ("mptcp: add struct mptcp_sched_ops")
> a7384f391875 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net")
(...)
> From a7cfe776637004a4c938fde78be4bd608c32c3ef Mon Sep 17 00:00:00 2001
> From: Paolo Abeni <pabeni@xxxxxxxxxx>
> Date: Thu, 15 Feb 2024 19:25:31 +0100
> Subject: [PATCH] mptcp: fix data races on local_id
>
> The local address id is accessed lockless by the NL PM, add
> all the required ONCE annotation. There is a caveat: the local
> id can be initialized late in the subflow life-cycle, and its
> validity is controlled by the local_id_valid flag.
>
> Remove such flag and encode the validity in the local_id field
> itself with negative value before initialization. That allows
> accessing the field consistently with a single read operation.
FYI, because of the various conflicts, and because the issue seems
unlikely is quite harmless -- e.g. a duplicated subflow is created --, I
think it is better not to try to backport this patch to v5.15 and older.
Cheers,
Matt
--
Sponsored by the NGI0 Core fund.
