From 0f1e4d06591d0a7907c71f7b6d1c79f8a4de8098 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Wed, 20 Jul 2022 09:50:19 -0700 Subject: 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 Signed-off-by: David S. Miller --- net/mptcp/options.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/mptcp') 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)); -- cgit v1.2.3