icsk->icsk_retransmits is read locklessly from inet_sk_diag_fill(), tcp_get_timestamping_opt_stats, get_tcp4_sock() and get_tcp6_sock(). Add corresponding READ_ONCE()/WRITE_ONCE() annotations. Signed-off-by: Eric Dumazet --- net/ipv4/inet_diag.c | 2 +- net/ipv4/tcp.c | 3 ++- net/ipv4/tcp_input.c | 6 +++--- net/ipv4/tcp_ipv4.c | 2 +- net/ipv4/tcp_output.c | 2 +- net/ipv4/tcp_timer.c | 2 +- net/ipv6/tcp_ipv6.c | 2 +- net/mptcp/protocol.c | 3 ++- 8 files changed, 12 insertions(+), 10 deletions(-) diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index 2fa53b16fe7788eed9796c8476157a77eced096c..35c1579e5bd4cef4a8c44d03ed1af16fe1735ac0 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -313,7 +313,7 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, icsk_pending == ICSK_TIME_REO_TIMEOUT || icsk_pending == ICSK_TIME_LOSS_PROBE) { r->idiag_timer = 1; - r->idiag_retrans = icsk->icsk_retransmits; + r->idiag_retrans = READ_ONCE(icsk->icsk_retransmits); r->idiag_expires = jiffies_delta_to_msecs(icsk_timeout(icsk) - jiffies); } else if (icsk_pending == ICSK_TIME_PROBE0) { diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 71a956fbfc5533224ee00e792de2cfdccd4d40aa..463281ad076fd3baeaee5f9131f0e2ffd947e90b 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -4348,7 +4348,8 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk, nla_put_u32(stats, TCP_NLA_REORDERING, tp->reordering); nla_put_u32(stats, TCP_NLA_MIN_RTT, tcp_min_rtt(tp)); - nla_put_u8(stats, TCP_NLA_RECUR_RETRANS, inet_csk(sk)->icsk_retransmits); + nla_put_u8(stats, TCP_NLA_RECUR_RETRANS, + READ_ONCE(inet_csk(sk)->icsk_retransmits)); nla_put_u8(stats, TCP_NLA_DELIVERY_RATE_APP_LMT, !!tp->rate_app_limited); nla_put_u32(stats, TCP_NLA_SND_SSTHRESH, tp->snd_ssthresh); nla_put_u32(stats, TCP_NLA_DELIVERED, tp->delivered); diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 71b76e98371a667b6e8263b32c242363672d7c5a..87f06e5acfe86411f5ea68e565f0c2bf4794ed53 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2569,7 +2569,7 @@ static bool tcp_try_undo_loss(struct sock *sk, bool frto_undo) if (frto_undo) NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSPURIOUSRTOS); - inet_csk(sk)->icsk_retransmits = 0; + WRITE_ONCE(inet_csk(sk)->icsk_retransmits, 0); if (tcp_is_non_sack_preventing_reopen(sk)) return true; if (frto_undo || tcp_is_sack(tp)) { @@ -3851,7 +3851,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) if (after(ack, prior_snd_una)) { flag |= FLAG_SND_UNA_ADVANCED; - icsk->icsk_retransmits = 0; + WRITE_ONCE(icsk->icsk_retransmits, 0); #if IS_ENABLED(CONFIG_TLS_DEVICE) if (static_branch_unlikely(&clean_acked_data_enabled.key)) @@ -6636,7 +6636,7 @@ static void tcp_rcv_synrecv_state_fastopen(struct sock *sk) tcp_try_undo_recovery(sk); tcp_update_rto_time(tp); - inet_csk(sk)->icsk_retransmits = 0; + WRITE_ONCE(inet_csk(sk)->icsk_retransmits, 0); /* In tcp_fastopen_synack_timer() on the first SYNACK RTO we set * retrans_stamp but don't enter CA_Loss, so in case that happened we * need to zero retrans_stamp here to prevent spurious diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 84d3d556ed8062d07fe7019bc0dadd90d3b80d96..5d549dfd4e601eedb7c5cc3f3e503a5bef7ed4a4 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2958,7 +2958,7 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i) rx_queue, timer_active, jiffies_delta_to_clock_t(timer_expires - jiffies), - icsk->icsk_retransmits, + READ_ONCE(icsk->icsk_retransmits), from_kuid_munged(seq_user_ns(f), sk_uid(sk)), icsk->icsk_probes_out, sock_i_ino(sk), diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index dfbac0876d96ee6b556fff5b6c9ec8fe2e04aa05..8623def6f88921130e1944f03eb5408e9e26120d 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -3954,7 +3954,7 @@ static void tcp_connect_init(struct sock *sk) WRITE_ONCE(tp->copied_seq, tp->rcv_nxt); inet_csk(sk)->icsk_rto = tcp_timeout_init(sk); - inet_csk(sk)->icsk_retransmits = 0; + WRITE_ONCE(inet_csk(sk)->icsk_retransmits, 0); tcp_clear_retrans(tp); } diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index a207877270fbdef6f86f61093aa476b6cd6f8706..8b11ab4cc9524f0e0066f474044a4c585115ec29 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -444,7 +444,7 @@ static void tcp_update_rto_stats(struct sock *sk) tp->total_rto_recoveries++; tp->rto_stamp = tcp_time_stamp_ms(tp); } - icsk->icsk_retransmits++; + WRITE_ONCE(icsk->icsk_retransmits, icsk->icsk_retransmits + 1); tp->total_rto++; } diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 7577e7eb2c97b821826f633a11dd5567dde7b7cb..7b177054452b983d3f49a06869950565c03c13ee 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -2230,7 +2230,7 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) rx_queue, timer_active, jiffies_delta_to_clock_t(timer_expires - jiffies), - icsk->icsk_retransmits, + READ_ONCE(icsk->icsk_retransmits), from_kuid_munged(seq_user_ns(seq), sk_uid(sp)), icsk->icsk_probes_out, sock_i_ino(sp), diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 9a287b75c1b31bac9c35581db996e39e594872e0..f2e728239480444ffdb297efc35303848d4c4a31 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2587,7 +2587,8 @@ static void __mptcp_retrans(struct sock *sk) if (mptcp_data_fin_enabled(msk)) { struct inet_connection_sock *icsk = inet_csk(sk); - icsk->icsk_retransmits++; + WRITE_ONCE(icsk->icsk_retransmits, + icsk->icsk_retransmits + 1); mptcp_set_datafin_timeout(sk); mptcp_send_ack(msk); -- 2.51.0.rc2.233.g662b1ed5c5-goog