From: Chenguang Zhao Date: Tue, 21 Jul 2026 22:14:38 +0000 (+0200) Subject: mptcp: decrement subflows counter on failed passive join X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=f3ca0ee2cc308e33896536789cbc5f3a12ca7b30;p=thirdparty%2Flinux.git mptcp: decrement subflows counter on failed passive join mptcp_pm_allow_new_subflow() increments extra_subflows before __mptcp_finish_join() on the passive MP_JOIN path. In case of race conditions, the subflow is dropped without calling mptcp_close_ssk(), so the counter is not rolled back. Call mptcp_pm_close_subflow() when the join completion fails to decrement the subflows counter. Fixes: 10f6d46c943d ("mptcp: fix race between MP_JOIN and close") Cc: stable@vger.kernel.org Signed-off-by: Chenguang Zhao Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20260722-net-mptcp-misc-fixes-7-2-rc5-v1-1-6fb595bc86ef@kernel.org Signed-off-by: Jakub Kicinski --- diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index cb9515f505aa..b32f0cd262a7 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -3907,6 +3907,7 @@ bool mptcp_finish_join(struct sock *ssk) mptcp_data_unlock(parent); if (!ret) { + mptcp_pm_close_subflow(msk); err_prohibited: subflow->reset_reason = MPTCP_RST_EPROHIBIT; return false;