Re: [PATCH 5.10.y] mptcp: pm: ADD_ADDR rtx: free sk if last

[Matthieu Baerts <matttbe@kernel.org>]

Hi Sasha,

On 19/05/2026 21:52, Sasha Levin wrote:
> From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
> 
> [ Upstream commit b7b9a461569734d33d3259d58d2507adfac107ed ]
> 
> When an ADD_ADDR is retransmitted, the sk is held in sk_reset_timer(),
> and released at the end.
> 
> If at that moment, it was the last reference being held, the sk would
> not be freed. sock_put() should then be called instead of __sock_put().
> 
> But that's not enough: if it is the last reference, sock_put() will call
> sk_free(), which will end up calling sk_stop_timer_sync() on the same
> timer, and waiting indefinitely to finish. So it is needed to mark that
> the timer is done at the end of the timer handler when it has not been
> rescheduled, not to call sk_stop_timer_sync() on "itself".
> 
> Fixes: 00cfd77b9063 ("mptcp: retransmit ADD_ADDR when timeout")
> Cc: stable@vger.kernel.org
> Reviewed-by: Mat Martineau <martineau@kernel.org>
> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
> Link: https://patch.msgid.link/20260505-net-mptcp-pm-fixes-7-1-rc3-v1-5-fca8091060a4@kernel.org
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> [ applied fix to pm_netlink.c instead of pm.c due to pre-split file layout ]
> Signed-off-by: Sasha Levin <sashal@kernel.org>

See my comment for the same patch for 6.12: most conflicts fixed here
shouldn't exist if patches you sent earlier are applied first. So a new
version is needed.

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.