From: Kuniyuki Iwashima Date: Fri, 22 Jul 2022 18:21:59 +0000 (-0700) Subject: tcp: Fix data-races around sk_pacing_rate. X-Git-Tag: v5.15.73~1858 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a610feb170bfb381c090620d30d7ee72505ce001;p=platform%2Fkernel%2Flinux-rpi.git tcp: Fix data-races around sk_pacing_rate. [ Upstream commit 59bf6c65a09fff74215517aecffbbdcd67df76e3 ] 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 Signed-off-by: Sasha Levin --- diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 018be3f..566745f5 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -902,9 +902,9 @@ 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);