diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-15 10:17:54 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-07-18 12:21:54 +0100 |
| commit | 5a54213318c43f4009ae158347aa6016e3b9b55a (patch) | |
| tree | 35efe5034a35dcd8dbee8b0d93d7c03b48dc2d87 /net/ipv4/tcp.c | |
| parent | 79539f34743d3e14cc1fa6577d326a82cc64d62f (diff) | |
| download | linux-5a54213318c43f4009ae158347aa6016e3b9b55a.tar.bz2 | |
tcp: Fix data-races around sysctl_tcp_fastopen.
While reading sysctl_tcp_fastopen, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its readers.
Fixes: 2100c8d2d9db ("net-tcp: Fast Open base")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp.c')
| -rw-r--r-- | net/ipv4/tcp.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index b1b1bcbc4f60..2faaaaf540ac 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1150,7 +1150,8 @@ static int tcp_sendmsg_fastopen(struct sock *sk, struct msghdr *msg, struct sockaddr *uaddr = msg->msg_name; int err, flags; - if (!(sock_net(sk)->ipv4.sysctl_tcp_fastopen & TFO_CLIENT_ENABLE) || + if (!(READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen) & + TFO_CLIENT_ENABLE) || (uaddr && msg->msg_namelen >= sizeof(uaddr->sa_family) && uaddr->sa_family == AF_UNSPEC)) return -EOPNOTSUPP; @@ -3617,7 +3618,8 @@ static int do_tcp_setsockopt(struct sock *sk, int level, int optname, case TCP_FASTOPEN_CONNECT: if (val > 1 || val < 0) { err = -EINVAL; - } else if (net->ipv4.sysctl_tcp_fastopen & TFO_CLIENT_ENABLE) { + } else if (READ_ONCE(net->ipv4.sysctl_tcp_fastopen) & + TFO_CLIENT_ENABLE) { if (sk->sk_state == TCP_CLOSE) tp->fastopen_connect = val; else |