From: Kuniyuki Iwashima Date: Wed, 13 Jul 2022 20:52:05 +0000 (-0700) Subject: tcp: Fix a data-race around sysctl_tcp_probe_interval. X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=2a85388f1d94a9f8b5a529118a2c5eaa0520d85c;p=linux.git tcp: Fix a data-race around sysctl_tcp_probe_interval. While reading sysctl_tcp_probe_interval, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 05cbc0db03e8 ("ipv4: Create probe timer for tcp PMTU as per RFC4821") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller --- diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index aa757c74dad44..02ab3a9c66574 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2283,7 +2283,7 @@ static inline void tcp_mtu_check_reprobe(struct sock *sk) u32 interval; s32 delta; - interval = net->ipv4.sysctl_tcp_probe_interval; + interval = READ_ONCE(net->ipv4.sysctl_tcp_probe_interval); delta = tcp_jiffies32 - icsk->icsk_mtup.probe_timestamp; if (unlikely(delta >= interval * HZ)) { int mss = tcp_current_mss(sk);