From 59bf6c65a09fff74215517aecffbbdcd67df76e3 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Fri, 22 Jul 2022 11:21:59 -0700 Subject: [PATCH] tcp: Fix data-races around sk_pacing_rate. While reading sysctl_tcp_pacing_(ss|ca)_ratio, they can be changed concurrently. Thus, we need to add READ_ONCE() to their readers. Fixes: 43e122b014c9 ("tcp: refine pacing rate determination") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller --- net/ipv4/tcp_input.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index c799f39..dd05238 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -910,9 +910,9 @@ static void tcp_update_pacing_rate(struct sock *sk) * end of slow start and should slow down. */ if (tcp_snd_cwnd(tp) < tp->snd_ssthresh / 2) - rate *= sock_net(sk)->ipv4.sysctl_tcp_pacing_ss_ratio; + rate *= READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_pacing_ss_ratio); else - rate *= sock_net(sk)->ipv4.sysctl_tcp_pacing_ca_ratio; + rate *= READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_pacing_ca_ratio); rate *= max(tcp_snd_cwnd(tp), tp->packets_out); -- 2.7.4