On 04/09/2019 12.44, Marc Kleine-Budde wrote:
From: Kurt Van Dijck <kurt.van.dijck@xxxxxx>
The size of this structure will be increased with J1939 support. To stay
binary compatible, the CAN_REQUIRED_SIZE macro is introduced for
existing CAN protocols.
Signed-off-by: Kurt Van Dijck <dev.kurt@xxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Acked-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
Thanks,
Oliver
---
include/linux/can/core.h | 8 ++++++++
net/can/bcm.c | 4 ++--
net/can/raw.c | 4 ++--
3 files changed, 12 insertions(+), 4 deletions(-)
diff --git a/include/linux/can/core.h b/include/linux/can/core.h
index 708c10d3417a..8339071ab08b 100644
--- a/include/linux/can/core.h
+++ b/include/linux/can/core.h
@@ -41,6 +41,14 @@ struct can_proto {
struct proto *prot;
};
+/* required_size
+ * macro to find the minimum size of a struct
+ * that includes a requested member
+ */
+#define CAN_REQUIRED_SIZE(struct_type, member) \
+ (offsetof(typeof(struct_type), member) + \
+ sizeof(((typeof(struct_type) *)(NULL))->member))
+
/* function prototypes for the CAN networklayer core (af_can.c) */
extern int can_proto_register(const struct can_proto *cp);
diff --git a/net/can/bcm.c b/net/can/bcm.c
index 28fd1a1c8487..c96fa0f33db3 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -1294,7 +1294,7 @@ static int bcm_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
/* no bound device as default => check msg_name */
DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
- if (msg->msg_namelen < sizeof(*addr))
+ if (msg->msg_namelen < CAN_REQUIRED_SIZE(*addr, can_ifindex))
return -EINVAL;
if (addr->can_family != AF_CAN)
@@ -1536,7 +1536,7 @@ static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len,
struct net *net = sock_net(sk);
int ret = 0;
- if (len < sizeof(*addr))
+ if (len < CAN_REQUIRED_SIZE(*addr, can_ifindex))
return -EINVAL;
lock_sock(sk);
diff --git a/net/can/raw.c b/net/can/raw.c
index fdbc36140e9b..59c039d73c6d 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -396,7 +396,7 @@ static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
int err = 0;
int notify_enetdown = 0;
- if (len < sizeof(*addr))
+ if (len < CAN_REQUIRED_SIZE(*addr, can_ifindex))
return -EINVAL;
if (addr->can_family != AF_CAN)
return -EINVAL;
@@ -733,7 +733,7 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
if (msg->msg_name) {
DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
- if (msg->msg_namelen < sizeof(*addr))
+ if (msg->msg_namelen < CAN_REQUIRED_SIZE(*addr, can_ifindex))
return -EINVAL;
if (addr->can_family != AF_CAN)
