commit 2aa39889c463195a0dfe2aff9fad413139c32a4f upstream
Commit 3ea566422cbd ("can: isotp: sanitize CAN ID checks in isotp_bind()") checks the given CAN ID address information by sanitizing the input values.
This check (silently) removes obsolete bits by masking the given CAN IDs.
Derek Will suggested to give a feedback to the application programmer when the 'sanitizing' was actually needed which means the programmer provided CAN ID content in a wrong format (e.g. SFF CAN IDs with a CAN ID > 0x7FF).
Link: https://lore.kernel.org/all/20220515181633.76671-1-socketcan@hartkopp.net Suggested-by: Derek Will derekrobertwill@gmail.com Signed-off-by: Oliver Hartkopp socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de --- net/can/isotp.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/net/can/isotp.c b/net/can/isotp.c index fb179a333784..902cb61b6495 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -1140,10 +1140,15 @@ static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len) if (rx_id & CAN_EFF_FLAG) rx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK); else rx_id &= CAN_SFF_MASK;
+ /* give feedback on wrong CAN-ID values */ + if (tx_id != addr->can_addr.tp.tx_id || + rx_id != addr->can_addr.tp.rx_id) + return -EINVAL; + if (!addr->can_ifindex) return -ENODEV;
lock_sock(sk);