can: j1939: j1939_tp_cmd_recv(): check the dst address of TP.CM_BAM

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: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Link: https://lore.kernel.org/all/1635431907-15617-4-git-send-email-zhangchangzhong@huawei.com
Cc: stable@vger.kernel.org
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Zhang Changzhong 2021-10-28 22:38:27 +08:00 committed by Marc Kleine-Budde
parent a79305e156
commit 164051a6ab
1 changed files with 5 additions and 0 deletions

View File

@ -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)