5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp
[ Upstream commit 06e02da29f6f1a45fc07bd60c7eaf172dc21e334 ]
Since j1939_sk_bind() and j1939_sk_release() call j1939_local_ecu_put() when J1939_SOCK_BOUND was already set, but the error handling path for j1939_sk_bind() will not set J1939_SOCK_BOUND when j1939_local_ecu_get() fails, j1939_local_ecu_get() needs to undo priv->ents[sa].nusers++ when j1939_local_ecu_get() returns an error.
Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") 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/e7f80046-4ff7-4ce2-8ad8-7c3c678a42c9@I-love.SAKURA.... Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org --- net/can/j1939/bus.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/net/can/j1939/bus.c b/net/can/j1939/bus.c index 4866879016021..e0b966c2517cf 100644 --- a/net/can/j1939/bus.c +++ b/net/can/j1939/bus.c @@ -290,8 +290,11 @@ int j1939_local_ecu_get(struct j1939_priv *priv, name_t name, u8 sa) if (!ecu) ecu = j1939_ecu_create_locked(priv, name); err = PTR_ERR_OR_ZERO(ecu); - if (err) + if (err) { + if (j1939_address_is_unicast(sa)) + priv->ents[sa].nusers--; goto done; + }
ecu->nusers++; /* TODO: do we care if ecu->addr != sa? */