From 15cc10453398c22f78f6c2b897119ecce5e5dd89 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Thu, 11 Feb 2021 15:30:37 -0800 Subject: mptcp: deliver ssk errors to msk Currently all errors received on msk subflows are ignored. We need to catch at least the errors on connect() and on fallback sockets. Use a custom sk_error_report callback at subflow level, and do the real action under the msk socket lock - via the usual sock_owned_by_user()/release_callback() schema. Fixes: 6e628cd3a8f7 ("mptcp: use mptcp release_cb for delayed tasks") Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- net/mptcp/subflow.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) (limited to 'net/mptcp/subflow.c') diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 278cbe3e539e..0ec3ccac6bb4 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -1043,6 +1043,46 @@ static void subflow_write_space(struct sock *ssk) /* we take action in __mptcp_clean_una() */ } +void __mptcp_error_report(struct sock *sk) +{ + struct mptcp_subflow_context *subflow; + struct mptcp_sock *msk = mptcp_sk(sk); + + mptcp_for_each_subflow(msk, subflow) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + int err = sock_error(ssk); + + if (!err) + continue; + + /* only propagate errors on fallen-back sockets or + * on MPC connect + */ + if (sk->sk_state != TCP_SYN_SENT && !__mptcp_check_fallback(msk)) + continue; + + inet_sk_state_store(sk, inet_sk_state_load(ssk)); + sk->sk_err = -err; + + /* This barrier is coupled with smp_rmb() in mptcp_poll() */ + smp_wmb(); + sk->sk_error_report(sk); + break; + } +} + +static void subflow_error_report(struct sock *ssk) +{ + struct sock *sk = mptcp_subflow_ctx(ssk)->conn; + + mptcp_data_lock(sk); + if (!sock_owned_by_user(sk)) + __mptcp_error_report(sk); + else + set_bit(MPTCP_ERROR_REPORT, &mptcp_sk(sk)->flags); + mptcp_data_unlock(sk); +} + static struct inet_connection_sock_af_ops * subflow_default_af_ops(struct sock *sk) { @@ -1352,9 +1392,11 @@ static int subflow_ulp_init(struct sock *sk) ctx->tcp_data_ready = sk->sk_data_ready; ctx->tcp_state_change = sk->sk_state_change; ctx->tcp_write_space = sk->sk_write_space; + ctx->tcp_error_report = sk->sk_error_report; sk->sk_data_ready = subflow_data_ready; sk->sk_write_space = subflow_write_space; sk->sk_state_change = subflow_state_change; + sk->sk_error_report = subflow_error_report; out: return err; } @@ -1407,6 +1449,7 @@ static void subflow_ulp_clone(const struct request_sock *req, new_ctx->tcp_data_ready = old_ctx->tcp_data_ready; new_ctx->tcp_state_change = old_ctx->tcp_state_change; new_ctx->tcp_write_space = old_ctx->tcp_write_space; + new_ctx->tcp_error_report = old_ctx->tcp_error_report; new_ctx->rel_write_seq = 1; new_ctx->tcp_sock = newsk; -- cgit v1.2.3