tcp: Fix data-races around keepalive sysctl knobs.

[ Upstream commit f2f316e287e6c2e3a1c5bab8d9b77ee03daa0463 ]

While reading sysctl_tcp_keepalive_(time|probes|intvl), they can be changed
concurrently.  Thus, we need to add READ_ONCE() to their readers.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Kuniyuki Iwashima 2022-07-15 10:17:45 -07:00 committed by Greg Kroah-Hartman
parent f85119fb3f
commit fc489055e7
2 changed files with 7 additions and 4 deletions

View File

@ -1447,21 +1447,24 @@ static inline int keepalive_intvl_when(const struct tcp_sock *tp)
{
struct net *net = sock_net((struct sock *)tp);
return tp->keepalive_intvl ? : net->ipv4.sysctl_tcp_keepalive_intvl;
return tp->keepalive_intvl ? :
READ_ONCE(net->ipv4.sysctl_tcp_keepalive_intvl);
}
static inline int keepalive_time_when(const struct tcp_sock *tp)
{
struct net *net = sock_net((struct sock *)tp);
return tp->keepalive_time ? : net->ipv4.sysctl_tcp_keepalive_time;
return tp->keepalive_time ? :
READ_ONCE(net->ipv4.sysctl_tcp_keepalive_time);
}
static inline int keepalive_probes(const struct tcp_sock *tp)
{
struct net *net = sock_net((struct sock *)tp);
return tp->keepalive_probes ? : net->ipv4.sysctl_tcp_keepalive_probes;
return tp->keepalive_probes ? :
READ_ONCE(net->ipv4.sysctl_tcp_keepalive_probes);
}
static inline u32 keepalive_time_elapsed(const struct tcp_sock *tp)

View File

@ -1787,7 +1787,7 @@ void smc_llc_lgr_init(struct smc_link_group *lgr, struct smc_sock *smc)
init_waitqueue_head(&lgr->llc_flow_waiter);
init_waitqueue_head(&lgr->llc_msg_waiter);
mutex_init(&lgr->llc_conf_mutex);
lgr->llc_testlink_time = net->ipv4.sysctl_tcp_keepalive_time;
lgr->llc_testlink_time = READ_ONCE(net->ipv4.sysctl_tcp_keepalive_time);
}
/* called after lgr was removed from lgr_list */