diff options
| author | Oleksij Rempel <o.rempel@pengutronix.de> | 2021-06-17 15:06:23 +0200 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2021-06-19 23:54:00 +0200 |
| commit | 22c696fed25c63c7f67508309820358b94a96b6d (patch) | |
| tree | 73f5fa7199d0721932570c9700ab952166869763 /net/can/j1939 | |
| parent | 14a4696bc3118ba49da28f79280e1d55603aa737 (diff) | |
can: j1939: j1939_sk_init(): set SOCK_RCU_FREE to call sk_destruct() after RCU is done
Set SOCK_RCU_FREE to let RCU to call sk_destruct() on completion.
Without this patch, we will run in to j1939_can_recv() after priv was
freed by j1939_sk_release()->j1939_sk_sock_destruct()
Fixes: 25fe97cb7620 ("can: j1939: move j1939_priv_put() into sk_destruct callback")
Link: https://lore.kernel.org/r/20210617130623.12705-1-o.rempel@pengutronix.de
Cc: linux-stable <stable@vger.kernel.org>
Reported-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Reported-by: syzbot+bdf710cfc41c186fdff3@syzkaller.appspotmail.com
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'net/can/j1939')
| -rw-r--r-- | net/can/j1939/main.c | 4 | ||||
| -rw-r--r-- | net/can/j1939/socket.c | 3 |
2 files changed, 7 insertions, 0 deletions
diff --git a/net/can/j1939/main.c b/net/can/j1939/main.c index da3a7a7bcff2..08c8606cfd9c 100644 --- a/net/can/j1939/main.c +++ b/net/can/j1939/main.c @@ -193,6 +193,10 @@ static void j1939_can_rx_unregister(struct j1939_priv *priv) can_rx_unregister(dev_net(ndev), ndev, J1939_CAN_ID, J1939_CAN_MASK, j1939_can_recv, priv); + /* The last reference of priv is dropped by the RCU deferred + * j1939_sk_sock_destruct() of the last socket, so we can + * safely drop this reference here. + */ j1939_priv_put(priv); } diff --git a/net/can/j1939/socket.c b/net/can/j1939/socket.c index 56aa66147d5a..fce8bc8afeb7 100644 --- a/net/can/j1939/socket.c +++ b/net/can/j1939/socket.c @@ -398,6 +398,9 @@ static int j1939_sk_init(struct sock *sk) atomic_set(&jsk->skb_pending, 0); spin_lock_init(&jsk->sk_session_queue_lock); INIT_LIST_HEAD(&jsk->sk_session_queue); + + /* j1939_sk_sock_destruct() depends on SOCK_RCU_FREE flag */ + sock_set_flag(sk, SOCK_RCU_FREE); sk->sk_destruct = j1939_sk_sock_destruct; sk->sk_protocol = CAN_J1939; |