diff options
| author | Kuniyuki Iwashima <kuniyu@amazon.com> | 2022-07-20 09:50:19 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-08-03 12:05:29 +0200 |
| commit | 5bb0140ea9a9fc87265938ff416312bfe19bfddd (patch) | |
| tree | feebb5929f875f8e92a19c922a8c5a400dd3f0a9 | |
| parent | 5cd3256fc54d13194bb48857fe2685db293cf175 (diff) | |
tcp: Fix data-races around sysctl_tcp_workaround_signed_windows.
[ Upstream commit 0f1e4d06591d0a7907c71f7b6d1c79f8a4de8098 ]
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/ipv4/tcp_output.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 66836b8bd46f..a7f0a1f0c2a3 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -227,7 +227,7 @@ 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); @@ -282,7 +282,7 @@ 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)); |