From: Oliver Hartkopp socketcan@hartkopp.net
[ Upstream commit f522d9559b07854c231cf8f0b8cb5a3578f8b44e ]
Since commit f5223e9eee65 ("can: extend sockaddr_can to include j1939 members") the sockaddr_can has been extended in size and a new CAN_REQUIRED_SIZE macro has been introduced to calculate the protocol specific needed size.
The ABI for the msg_name and msg_namelen has not been adapted to the new CAN_REQUIRED_SIZE macro for the other CAN protocols which leads to a problem when an existing binary reads the (increased) struct sockaddr_can in msg_name.
Fixes: e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol") Reported-by: Richard Weinberger richard@nod.at Acked-by: Kurt Van Dijck dev.kurt@vandijck-laurijssen.be Link: https://lore.kernel.org/linux-can/1135648123.112255.1616613706554.JavaMail.z... Link: https://lore.kernel.org/r/20210325125850.1620-2-socketcan@hartkopp.net Signed-off-by: Oliver Hartkopp socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org --- net/can/isotp.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/net/can/isotp.c b/net/can/isotp.c index ea1e227b8e54..d5780ab29e09 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -77,6 +77,8 @@ MODULE_LICENSE("Dual BSD/GPL"); MODULE_AUTHOR("Oliver Hartkopp socketcan@hartkopp.net"); MODULE_ALIAS("can-proto-6");
+#define ISOTP_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.tp) + #define SINGLE_MASK(id) (((id) & CAN_EFF_FLAG) ? \ (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \ (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG)) @@ -981,7 +983,8 @@ static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, sock_recv_timestamp(msg, sk, skb);
if (msg->msg_name) { - msg->msg_namelen = sizeof(struct sockaddr_can); + __sockaddr_check_size(ISOTP_MIN_NAMELEN); + msg->msg_namelen = ISOTP_MIN_NAMELEN; memcpy(msg->msg_name, skb->cb, msg->msg_namelen); }
@@ -1050,7 +1053,7 @@ static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len) int err = 0; int notify_enetdown = 0;
- if (len < CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.tp)) + if (len < ISOTP_MIN_NAMELEN) return -EINVAL;
if (addr->can_addr.tp.rx_id == addr->can_addr.tp.tx_id) @@ -1136,13 +1139,13 @@ static int isotp_getname(struct socket *sock, struct sockaddr *uaddr, int peer) if (peer) return -EOPNOTSUPP;
- memset(addr, 0, sizeof(*addr)); + memset(addr, 0, ISOTP_MIN_NAMELEN); addr->can_family = AF_CAN; addr->can_ifindex = so->ifindex; addr->can_addr.tp.rx_id = so->rxid; addr->can_addr.tp.tx_id = so->txid;
- return sizeof(*addr); + return ISOTP_MIN_NAMELEN; }
static int isotp_setsockopt(struct socket *sock, int level, int optname,