tcp: annotate data-races around tp->linger2

[ Upstream commit 9df5335ca974e688389c875546e5819778a80d59 ]

do_tcp_getsockopt() reads tp->linger2 while another cpu
might change its value.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230719212857.3943972-8-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Eric Dumazet 2023-07-19 21:28:53 +00:00 committed by Greg Kroah-Hartman
parent e639397202
commit 17c3d75833

View File

@ -3691,11 +3691,11 @@ int do_tcp_setsockopt(struct sock *sk, int level, int optname,
case TCP_LINGER2:
if (val < 0)
tp->linger2 = -1;
WRITE_ONCE(tp->linger2, -1);
else if (val > TCP_FIN_TIMEOUT_MAX / HZ)
tp->linger2 = TCP_FIN_TIMEOUT_MAX;
WRITE_ONCE(tp->linger2, TCP_FIN_TIMEOUT_MAX);
else
tp->linger2 = val * HZ;
WRITE_ONCE(tp->linger2, val * HZ);
break;
case TCP_DEFER_ACCEPT:
@ -4099,7 +4099,7 @@ int do_tcp_getsockopt(struct sock *sk, int level,
READ_ONCE(net->ipv4.sysctl_tcp_syn_retries);
break;
case TCP_LINGER2:
val = tp->linger2;
val = READ_ONCE(tp->linger2);
if (val >= 0)
val = (val ? : READ_ONCE(net->ipv4.sysctl_tcp_fin_timeout)) / HZ;
break;