From: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
[ 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@xxxxxx>
Acked-by: Kurt Van Dijck <dev.kurt@xxxxxxxxxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/linux-can/1135648123.112255.1616613706554.JavaMail.zimbra@xxxxxx/T/#t
Link: https://lore.kernel.org/r/20210325125850.1620-2-socketcan@xxxxxxxxxxxx
Signed-off-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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@xxxxxxxxxxxx>");
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,
--
2.30.2
