diff options
| author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2025-11-25 22:43:12 +0900 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2025-12-17 10:47:33 +0100 |
| commit | 46cea215dc9444ec32a76b1b6a9cb809e17b64d5 (patch) | |
| tree | 0f0debe77ebc850d4136b9c76693f34ccb608fbb /net | |
| parent | 5d5602236f5db19e8b337a2cd87a90ace5ea776d (diff) | |
can: j1939: make j1939_sk_bind() fail if device is no longer registered
There is a theoretical race window in j1939_sk_netdev_event_unregister()
where two j1939_sk_bind() calls jump in between read_unlock_bh() and
lock_sock().
The assumption jsk->priv == priv can fail if the first j1939_sk_bind()
call once made jsk->priv == NULL due to failed j1939_local_ecu_get() call
and the second j1939_sk_bind() call again made jsk->priv != NULL due to
successful j1939_local_ecu_get() call.
Since the socket lock is held by both j1939_sk_netdev_event_unregister()
and j1939_sk_bind(), checking ndev->reg_state with the socket lock held can
reliably make the second j1939_sk_bind() call fail (and close this race
window).
Fixes: 7fcbe5b2c6a4 ("can: j1939: implement NETDEV_UNREGISTER notification handler")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://patch.msgid.link/5732921e-247e-4957-a364-da74bd7031d7@I-love.SAKURA.ne.jp
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'net')
| -rw-r--r-- | net/can/j1939/socket.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/net/can/j1939/socket.c b/net/can/j1939/socket.c index 6272326dd614..ff9c4fd7b433 100644 --- a/net/can/j1939/socket.c +++ b/net/can/j1939/socket.c @@ -482,6 +482,12 @@ static int j1939_sk_bind(struct socket *sock, struct sockaddr_unsized *uaddr, in goto out_release_sock; } + if (ndev->reg_state != NETREG_REGISTERED) { + dev_put(ndev); + ret = -ENODEV; + goto out_release_sock; + } + can_ml = can_get_ml_priv(ndev); if (!can_ml) { dev_put(ndev); |