diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-20 19:50:19 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-07-22 14:06:17 +0300 |
| commit | 0f1e4d06591d0a7907c71f7b6d1c79f8a4de8098 (patch) | |
| tree | 5dc1a8cbc4a9887bbf7c43a97bcec98835173e4e | |
| parent | 780476488844e070580bfc9e3bc7832ec1cea883 (diff) | |
| download | linux-0f1e4d06591d0a7907c71f7b6d1c79f8a4de8098.tar.xz | |
tcp: Fix data-races around sysctl_tcp_workaround_signed_windows.
While reading sysctl_tcp_workaround_signed_windows, it can be changed
concurrently. Thus, we need to add READ_ONCE() to its readers.
Fixes: 15d99e02baba ("[TCP]: sysctl to allow TCP window > 32767 sans wscale")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/tcp_output.c | 4 | ||||
| -rw-r--r-- | net/mptcp/options.c | 2 |
2 files changed, 3 insertions, 3 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index c38e07b50639..88f7d51e6691 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -230,7 +230,7 @@ void tcp_select_initial_window(const struct sock *sk, int __space, __u32 mss, * which we interpret as a sign the remote TCP is not * misinterpreting the window field as a signed quantity. */ - if (sock_net(sk)->ipv4.sysctl_tcp_workaround_signed_windows) + if (READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_workaround_signed_windows)) (*rcv_wnd) = min(space, MAX_TCP_WINDOW); else (*rcv_wnd) = min_t(u32, space, U16_MAX); @@ -285,7 +285,7 @@ static u16 tcp_select_window(struct sock *sk) * scaled window. */ if (!tp->rx_opt.rcv_wscale && - sock_net(sk)->ipv4.sysctl_tcp_workaround_signed_windows) + READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_workaround_signed_windows)) new_win = min(new_win, MAX_TCP_WINDOW); else new_win = min(new_win, (65535U << tp->rx_opt.rcv_wscale)); diff --git a/net/mptcp/options.c b/net/mptcp/options.c index bd8f0f425be4..30d289044e71 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -1271,7 +1271,7 @@ raise_win: if (unlikely(th->syn)) new_win = min(new_win, 65535U) << tp->rx_opt.rcv_wscale; if (!tp->rx_opt.rcv_wscale && - sock_net(ssk)->ipv4.sysctl_tcp_workaround_signed_windows) + READ_ONCE(sock_net(ssk)->ipv4.sysctl_tcp_workaround_signed_windows)) new_win = min(new_win, MAX_TCP_WINDOW); else new_win = min(new_win, (65535U << tp->rx_opt.rcv_wscale)); |