tcp: Fix a data-race around sysctl_tcp_app_win.

commit 02ca527ac5581cf56749db9fd03d854e842253dd upstream.

While reading sysctl_tcp_app_win, 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 09:50:13 -07:00 committed by Greg Kroah-Hartman
parent f10a5f905a
commit 3cddb7a7a5

View File

@ -503,7 +503,7 @@ static void tcp_grow_window(struct sock *sk, const struct sk_buff *skb)
*/
static void tcp_init_buffer_space(struct sock *sk)
{
int tcp_app_win = sock_net(sk)->ipv4.sysctl_tcp_app_win;
int tcp_app_win = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_app_win);
struct tcp_sock *tp = tcp_sk(sk);
int maxwin;