[PATCH 5.14 160/849] can: j1939: j1939_can_recv(): ignore messages with invalid source address

From: Greg Kroah-Hartman
Date: Mon Nov 15 2021 - 17:00:11 EST


From: Zhang Changzhong <zhangchangzhong@xxxxxxxxxx>

commit a79305e156db3d24fcd8eb649cdb3c3b2350e5c2 upstream.

According to SAE-J1939-82 2015 (A.3.6 Row 2), a receiver should never
send TP.CM_CTS to the global address, so we can add a check in
j1939_can_recv() to drop messages with invalid source address.

Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Link: https://lore.kernel.org/all/1635431907-15617-3-git-send-email-zhangchangzhong@xxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Zhang Changzhong <zhangchangzhong@xxxxxxxxxx>
Acked-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/can/j1939/main.c | 7 +++++++
1 file changed, 7 insertions(+)

--- a/net/can/j1939/main.c
+++ b/net/can/j1939/main.c
@@ -75,6 +75,13 @@ static void j1939_can_recv(struct sk_buf
skcb->addr.pgn = (cf->can_id >> 8) & J1939_PGN_MAX;
/* set default message type */
skcb->addr.type = J1939_TP;
+
+ if (!j1939_address_is_valid(skcb->addr.sa)) {
+ netdev_err_once(priv->ndev, "%s: sa is broadcast address, ignoring!\n",
+ __func__);
+ goto done;
+ }
+
if (j1939_pgn_is_pdu1(skcb->addr.pgn)) {
/* Type 1: with destination address */
skcb->addr.da = skcb->addr.pgn;