6.12-stable review patch. If anyone has any objections, please let me know.
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From: Matthieu Baerts (NGI0) matttbe@kernel.org
[ Upstream commit 92da495cb65719583aa06bc946aeb18a10e1e6e2 ]
When TFO is used, the check to see if the 'C' flag (deny join id0) was set was bypassed.
This flag can be set when TFO is used, so the check should also be done when TFO is used.
Note that the set_fully_established label is also used when a 4th ACK is received. In this case, deny_join_id0 will not be set.
Fixes: dfc8d0603033 ("mptcp: implement delayed seq generation for passive fastopen") Reviewed-by: Mat Martineau martineau@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org Link: https://patch.msgid.link/20250912-net-mptcp-pm-uspace-deny_join_id0-v1-4-401... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/mptcp/options.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 7d4718a57bdcc..479a3bfa87aa2 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -985,13 +985,13 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk, return false; }
- if (mp_opt->deny_join_id0) - WRITE_ONCE(msk->pm.remote_deny_join_id0, true); - if (unlikely(!READ_ONCE(msk->pm.server_side))) pr_warn_once("bogus mpc option on established client sk");
set_fully_established: + if (mp_opt->deny_join_id0) + WRITE_ONCE(msk->pm.remote_deny_join_id0, true); + mptcp_data_lock((struct sock *)msk); __mptcp_subflow_fully_established(msk, subflow, mp_opt); mptcp_data_unlock((struct sock *)msk);