tcp: only release congestion control if it has been initialized

Currently, when cleaning up congestion control, we always call the
release regardless of whether it has been initialized. There is no
need to release when closing TCP_LISTEN and TCP_CLOSE (close
immediately after socket()).

In this case, tcp_cdg calls kfree(NULL) in release without causing
an exception, but for some customized ca, this could lead to
unexpected exceptions. We need to ensure that init and release are
called in pairs.

Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Link: https://patch.msgid.link/1729845944-6003-1-git-send-email-yangpc@wangsu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Pengcheng Yang 2024-10-25 16:45:44 +08:00 committed by Jakub Kicinski
parent 5b1c965956
commit cf44bd08cd
2 changed files with 3 additions and 2 deletions

View File

@ -3336,7 +3336,7 @@ int tcp_disconnect(struct sock *sk, int flags)
tp->window_clamp = 0;
tp->delivered = 0;
tp->delivered_ce = 0;
if (icsk->icsk_ca_ops->release)
if (icsk->icsk_ca_initialized && icsk->icsk_ca_ops->release)
icsk->icsk_ca_ops->release(sk);
memset(icsk->icsk_ca_priv, 0, sizeof(icsk->icsk_ca_priv));
icsk->icsk_ca_initialized = 0;

View File

@ -270,8 +270,9 @@ void tcp_cleanup_congestion_control(struct sock *sk)
{
struct inet_connection_sock *icsk = inet_csk(sk);
if (icsk->icsk_ca_ops->release)
if (icsk->icsk_ca_initialized && icsk->icsk_ca_ops->release)
icsk->icsk_ca_ops->release(sk);
icsk->icsk_ca_initialized = 0;
bpf_module_put(icsk->icsk_ca_ops, icsk->icsk_ca_ops->owner);
}