diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-18 10:26:48 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-07-20 10:14:50 +0100 |
| commit | 4845b5713ab18a1bb6e31d1fbb4d600240b8b691 (patch) | |
| tree | 3b1006f962476c31c415c8f357600aad22d32462 | |
| parent | 7c6f2a86ca590d5187a073d987e9599985fb1c7c (diff) | |
| download | linux-4845b5713ab18a1bb6e31d1fbb4d600240b8b691.tar.gz | |
tcp: Fix data-races around sysctl_tcp_slow_start_after_idle.
While reading sysctl_tcp_slow_start_after_idle, it can be changed
concurrently. Thus, we need to add READ_ONCE() to its readers.
Fixes: 35089bb203f4 ("[TCP]: Add tcp_slow_start_after_idle sysctl.")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/net/tcp.h | 4 | ||||
| -rw-r--r-- | net/ipv4/tcp_output.c | 2 |
2 files changed, 3 insertions, 3 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h index 6ee1fb4fb292e0..071735e10872c1 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1403,8 +1403,8 @@ static inline void tcp_slow_start_after_idle_check(struct sock *sk) struct tcp_sock *tp = tcp_sk(sk); s32 delta; - if (!sock_net(sk)->ipv4.sysctl_tcp_slow_start_after_idle || tp->packets_out || - ca_ops->cong_control) + if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_slow_start_after_idle) || + tp->packets_out || ca_ops->cong_control) return; delta = tcp_jiffies32 - tp->lsndtime; if (delta > inet_csk(sk)->icsk_rto) diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 898fcdcb7989b1..51120407c570de 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1898,7 +1898,7 @@ static void tcp_cwnd_validate(struct sock *sk, bool is_cwnd_limited) if (tp->packets_out > tp->snd_cwnd_used) tp->snd_cwnd_used = tp->packets_out; - if (sock_net(sk)->ipv4.sysctl_tcp_slow_start_after_idle && + if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_slow_start_after_idle) && (s32)(tcp_jiffies32 - tp->snd_cwnd_stamp) >= inet_csk(sk)->icsk_rto && !ca_ops->cong_control) tcp_cwnd_application_limited(sk); |