[PATCH net 3/8] can: j1939: j1939_tp_cmd_recv(): check the dst address of TP.CM_BAM
From: Marc Kleine-Budde <mkl@pengutronix.de>
Date: 2021-11-06 21:55:03
Also in:
linux-can, stable
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: Zhang Changzhong <redacted>
The TP.CM_BAM message must be sent to the global address [1], so add a
check to drop TP.CM_BAM sent to a non-global address.
Without this patch, the receiver will treat the following packets as
normal RTS/CTS transport:
18EC0102#20090002FF002301
18EB0102#0100000000000000
18EB0102#020000FFFFFFFFFF
[1] SAE-J1939-82 2015 A.3.3 Row 1.
Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Link: https://lore.kernel.org/all/1635431907-15617-4-git-send-email-zhangchangzhong@huawei.com (local)
Cc: stable@vger.kernel.org
Signed-off-by: Zhang Changzhong <redacted>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
net/can/j1939/transport.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index 05eb3d059e17..a271688780a2 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c@@ -2023,6 +2023,11 @@ static void j1939_tp_cmd_recv(struct j1939_priv *priv, struct sk_buff *skb) extd = J1939_ETP; fallthrough; case J1939_TP_CMD_BAM: + if (cmd == J1939_TP_CMD_BAM && !j1939_cb_is_broadcast(skcb)) { + netdev_err_once(priv->ndev, "%s: BAM to unicast (%02x), ignoring!\n", + __func__, skcb->addr.sa); + return; + } fallthrough; case J1939_TP_CMD_RTS: if (skcb->addr.type != extd)
--
2.33.0