| From | Greg Kroah-Hartman <> | Subject | [PATCH 5.15 124/201] tcp: Fix a data-race around sysctl_tcp_thin_linear_timeouts. | Date | Wed, 27 Jul 2022 18:10:28 +0200 |
| |
From: Kuniyuki Iwashima <kuniyu@amazon.com>
[ Upstream commit 7c6f2a86ca590d5187a073d987e9599985fb1c7c ]
While reading sysctl_tcp_thin_linear_timeouts, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader.
Fixes: 36e31b0af587 ("net: TCP thin linear timeouts") 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> --- net/ipv4/tcp_timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c index ec5277becc6a..50bba370486e 100644 --- a/net/ipv4/tcp_timer.c +++ b/net/ipv4/tcp_timer.c @@ -578,7 +578,7 @@ void tcp_retransmit_timer(struct sock *sk) * linear-timeout retransmissions into a black hole */ if (sk->sk_state == TCP_ESTABLISHED && - (tp->thin_lto || net->ipv4.sysctl_tcp_thin_linear_timeouts) && + (tp->thin_lto || READ_ONCE(net->ipv4.sysctl_tcp_thin_linear_timeouts)) && tcp_stream_is_thin(tp) && icsk->icsk_retransmits <= TCP_THIN_LINEAR_RETRIES) { icsk->icsk_backoff = 0; -- 2.35.1
|