From e4a0fa47e816e186f6b4c0055d07eeec42d11871 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Thu, 8 Feb 2024 19:03:52 +0100 Subject: mptcp: corner case locking for rx path fields initialization Most MPTCP-level related fields are under the mptcp data lock protection, but are written one-off without such lock at MPC complete time, both for the client and the server Leverage the mptcp_propagate_state() infrastructure to move such initialization under the proper lock client-wise. The server side critical init steps are done by mptcp_subflow_fully_established(): ensure the caller properly held the relevant lock, and avoid acquiring the same lock in the nested scopes. There are no real potential races, as write access to such fields is implicitly serialized by the MPTCP state machine; the primary goal is consistency. Fixes: d22f4988ffec ("mptcp: process MP_CAPABLE data option") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni Reviewed-by: Mat Martineau Signed-off-by: Matthieu Baerts (NGI0) Signed-off-by: David S. Miller --- net/mptcp/fastopen.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'net/mptcp/fastopen.c') diff --git a/net/mptcp/fastopen.c b/net/mptcp/fastopen.c index 74698582a285..ad28da655f8b 100644 --- a/net/mptcp/fastopen.c +++ b/net/mptcp/fastopen.c @@ -59,13 +59,12 @@ void mptcp_fastopen_subflow_synack_set_params(struct mptcp_subflow_context *subf mptcp_data_unlock(sk); } -void mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, - const struct mptcp_options_received *mp_opt) +void __mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_context *subflow, + const struct mptcp_options_received *mp_opt) { struct sock *sk = (struct sock *)msk; struct sk_buff *skb; - mptcp_data_lock(sk); skb = skb_peek_tail(&sk->sk_receive_queue); if (skb) { WARN_ON_ONCE(MPTCP_SKB_CB(skb)->end_seq); @@ -77,5 +76,4 @@ void mptcp_fastopen_gen_msk_ackseq(struct mptcp_sock *msk, struct mptcp_subflow_ } pr_debug("msk=%p ack_seq=%llx", msk, msk->ack_seq); - mptcp_data_unlock(sk); } -- cgit v1.2.3