tcp: Fix a data-race around sysctl_tcp_nometrics_save.

commit 8499a2454d9e8a55ce616ede9f9580f36fd5b0f3 upstream.

While reading sysctl_tcp_nometrics_save, it can be changed concurrently.
Thus, we need to add READ_ONCE() to its reader.

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Kuniyuki Iwashima 2022-07-20 09:50:16 -07:00 committed by Greg Kroah-Hartman
parent 79ea5b5190
commit 5e08afbdfb

View File

@ -329,7 +329,7 @@ void tcp_update_metrics(struct sock *sk)
int m;
sk_dst_confirm(sk);
if (net->ipv4.sysctl_tcp_nometrics_save || !dst)
if (READ_ONCE(net->ipv4.sysctl_tcp_nometrics_save) || !dst)
return;
rcu_read_lock();