| Message ID | 20220715171755.38497-15-kuniyu@amazon.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 5a54213318c43f4009ae158347aa6016e3b9b55a |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | sysctl: Fix data-races around ipv4_net_table (Round 3). | expand |
On Fri, Jul 15, 2022 at 10:21 AM Kuniyuki Iwashima <kuniyu@amazon.com> wrote: > > 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> > --- > CC: Yuchung Cheng <ycheng@google.com> Thanks for the improvement Acked-by: Yuchung Cheng <ycheng@google.com> > --- > net/ipv4/af_inet.c | 2 +- > net/ipv4/tcp.c | 6 ++++-- > net/ipv4/tcp_fastopen.c | 4 ++-- > 3 files changed, 7 insertions(+), 5 deletions(-) > > diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c > index 4bc24f9e38b3..59a0c5406fc1 100644 > --- a/net/ipv4/af_inet.c > +++ b/net/ipv4/af_inet.c > @@ -217,7 +217,7 @@ int inet_listen(struct socket *sock, int backlog) > * because the socket was in TCP_LISTEN state previously but > * was shutdown() rather than close(). > */ > - tcp_fastopen = sock_net(sk)->ipv4.sysctl_tcp_fastopen; > + tcp_fastopen = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen); > if ((tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) && > (tcp_fastopen & TFO_SERVER_ENABLE) && > !inet_csk(sk)->icsk_accept_queue.fastopenq.max_qlen) { > 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 > diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c > index fdbcf2a6d08e..0acdb5473850 100644 > --- a/net/ipv4/tcp_fastopen.c > +++ b/net/ipv4/tcp_fastopen.c > @@ -332,7 +332,7 @@ static bool tcp_fastopen_no_cookie(const struct sock *sk, > const struct dst_entry *dst, > int flag) > { > - return (sock_net(sk)->ipv4.sysctl_tcp_fastopen & flag) || > + return (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen) & flag) || > tcp_sk(sk)->fastopen_no_cookie || > (dst && dst_metric(dst, RTAX_FASTOPEN_NO_COOKIE)); > } > @@ -347,7 +347,7 @@ struct sock *tcp_try_fastopen(struct sock *sk, struct sk_buff *skb, > const struct dst_entry *dst) > { > bool syn_data = TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq + 1; > - int tcp_fastopen = sock_net(sk)->ipv4.sysctl_tcp_fastopen; > + int tcp_fastopen = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen); > struct tcp_fastopen_cookie valid_foc = { .len = -1 }; > struct sock *child; > int ret = 0; > -- > 2.30.2 >
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 4bc24f9e38b3..59a0c5406fc1 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -217,7 +217,7 @@ int inet_listen(struct socket *sock, int backlog) * because the socket was in TCP_LISTEN state previously but * was shutdown() rather than close(). */ - tcp_fastopen = sock_net(sk)->ipv4.sysctl_tcp_fastopen; + tcp_fastopen = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen); if ((tcp_fastopen & TFO_SERVER_WO_SOCKOPT1) && (tcp_fastopen & TFO_SERVER_ENABLE) && !inet_csk(sk)->icsk_accept_queue.fastopenq.max_qlen) { 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 diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c index fdbcf2a6d08e..0acdb5473850 100644 --- a/net/ipv4/tcp_fastopen.c +++ b/net/ipv4/tcp_fastopen.c @@ -332,7 +332,7 @@ static bool tcp_fastopen_no_cookie(const struct sock *sk, const struct dst_entry *dst, int flag) { - return (sock_net(sk)->ipv4.sysctl_tcp_fastopen & flag) || + return (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen) & flag) || tcp_sk(sk)->fastopen_no_cookie || (dst && dst_metric(dst, RTAX_FASTOPEN_NO_COOKIE)); } @@ -347,7 +347,7 @@ struct sock *tcp_try_fastopen(struct sock *sk, struct sk_buff *skb, const struct dst_entry *dst) { bool syn_data = TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(skb)->seq + 1; - int tcp_fastopen = sock_net(sk)->ipv4.sysctl_tcp_fastopen; + int tcp_fastopen = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_fastopen); struct tcp_fastopen_cookie valid_foc = { .len = -1 }; struct sock *child; int ret = 0;
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> --- CC: Yuchung Cheng <ycheng@google.com> --- net/ipv4/af_inet.c | 2 +- net/ipv4/tcp.c | 6 ++++-- net/ipv4/tcp_fastopen.c | 4 ++-- 3 files changed, 7 insertions(+), 5 deletions(-)