[PATCH net 4/7] can: j1939: j1939_sk_bind(): call j1939_priv_put() immediately when j1939_local_ecu_get() failed
From: Marc Kleine-Budde <mkl@pengutronix.de>
Date: 2025-09-10 16:29:15
Also in:
linux-can
Subsystem:
can network layer, can-j1939 network layer, the rest · Maintainers:
Oliver Hartkopp, Marc Kleine-Budde, Robin van der Gracht, Oleksij Rempel, Linus Torvalds
From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Commit 25fe97cb7620 ("can: j1939: move j1939_priv_put() into sk_destruct
callback") expects that a call to j1939_priv_put() can be unconditionally
delayed until j1939_sk_sock_destruct() is called. But a refcount leak will
happen when j1939_sk_bind() is called again after j1939_local_ecu_get()
from previous j1939_sk_bind() call returned an error. We need to call
j1939_priv_put() before j1939_sk_bind() returns an error.
Fixes: 25fe97cb7620 ("can: j1939: move j1939_priv_put() into sk_destruct callback")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://patch.msgid.link/4f49a1bc-a528-42ad-86c0-187268ab6535@I-love.SAKURA.ne.jp
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
net/can/j1939/socket.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/net/can/j1939/socket.c b/net/can/j1939/socket.c
index 70ebc861ea2a..88e7160d4248 100644
--- a/net/can/j1939/socket.c
+++ b/net/can/j1939/socket.c@@ -521,6 +521,9 @@ static int j1939_sk_bind(struct socket *sock, struct sockaddr *uaddr, int len) ret = j1939_local_ecu_get(priv, jsk->addr.src_name, jsk->addr.sa); if (ret) { j1939_netdev_stop(priv); + jsk->priv = NULL; + synchronize_rcu(); + j1939_priv_put(priv); goto out_release_sock; }
--
2.51.0