Merge tag 'linux-can-fixes-for-5.12-20210329' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can

Marc Kleine-Budde says:

====================
pull-request: can 2021-03-29

this is a pull request of 3 patches for net/master.

The two patch are by Oliver Hartkopp. He fixes length check in the
proto_ops::getname callback for the CAN RAW, BCM and ISOTP protocols,
which were broken by the introduction of the J1939 protocol.

The last patch is by me and fixes the a BUILD_BUG_ON() check which
triggers on ARCH=arm with CONFIG_AEABI unset.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 22 insertions, 15 deletions

diff --git a/include/uapi/linux/can.h b/include/uapi/linux/can.h
index f75238ac6dce..c7535352fef6 100644
--- a/include/uapi/linux/can.h
+++ b/include/uapi/linux/can.h
@@ -113,7 +113,7 @@ struct can_frame {
 		 */
 		__u8 len;
 		__u8 can_dlc; /* deprecated */
-	};
+	} __attribute__((packed)); /* disable padding added in some ABIs */
 	__u8 __pad; /* padding */
 	__u8 __res0; /* reserved / padding */
 	__u8 len8_dlc; /* optional DLC for 8 byte payload length (9 .. 15) */
diff --git a/net/can/bcm.c b/net/can/bcm.c
index 0e5c37be4a2b..909b9e684e04 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -86,6 +86,8 @@ MODULE_LICENSE("Dual BSD/GPL");
 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
 MODULE_ALIAS("can-proto-2");
 
+#define BCM_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_ifindex)
+
 /*
  * easy access to the first 64 bit of can(fd)_frame payload. cp->data is
  * 64 bit aligned so the offset has to be multiples of 8 which is ensured
@@ -1292,7 +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 < CAN_REQUIRED_SIZE(*addr, can_ifindex))
+		if (msg->msg_namelen < BCM_MIN_NAMELEN)
 			return -EINVAL;
 
 		if (addr->can_family != AF_CAN)
@@ -1534,7 +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 < CAN_REQUIRED_SIZE(*addr, can_ifindex))
+	if (len < BCM_MIN_NAMELEN)
 		return -EINVAL;
 
 	lock_sock(sk);
@@ -1616,8 +1618,8 @@ static int bcm_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	sock_recv_ts_and_drops(msg, sk, skb);
 
 	if (msg->msg_name) {
-		__sockaddr_check_size(sizeof(struct sockaddr_can));
-		msg->msg_namelen = sizeof(struct sockaddr_can);
+		__sockaddr_check_size(BCM_MIN_NAMELEN);
+		msg->msg_namelen = BCM_MIN_NAMELEN;
 		memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
 	}
 
diff --git a/net/can/isotp.c b/net/can/isotp.c
index 15ea1234d457..9f94ad3caee9 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))
@@ -986,7 +988,8 @@ 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);
 	}
 
@@ -1056,7 +1059,7 @@ static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len)
 	int notify_enetdown = 0;
 	int do_rx_reg = 1;
 
-	if (len < CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.tp))
+	if (len < ISOTP_MIN_NAMELEN)
 		return -EINVAL;
 
 	/* do not register frame reception for functional addressing */
@@ -1152,13 +1155,13 @@ 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,
diff --git a/net/can/raw.c b/net/can/raw.c
index 37b47a39a3ed..139d9471ddcf 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -60,6 +60,8 @@ MODULE_LICENSE("Dual BSD/GPL");
 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
 MODULE_ALIAS("can-proto-1");
 
+#define RAW_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_ifindex)
+
 #define MASK_ALL 0
 
 /* A raw socket has a list of can_filters attached to it, each receiving
@@ -394,7 +396,7 @@ static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
 	int err = 0;
 	int notify_enetdown = 0;
 
-	if (len < CAN_REQUIRED_SIZE(*addr, can_ifindex))
+	if (len < RAW_MIN_NAMELEN)
 		return -EINVAL;
 	if (addr->can_family != AF_CAN)
 		return -EINVAL;
@@ -475,11 +477,11 @@ static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
 	if (peer)
 		return -EOPNOTSUPP;
 
-	memset(addr, 0, sizeof(*addr));
+	memset(addr, 0, RAW_MIN_NAMELEN);
 	addr->can_family  = AF_CAN;
 	addr->can_ifindex = ro->ifindex;
 
-	return sizeof(*addr);
+	return RAW_MIN_NAMELEN;
 }
 
 static int raw_setsockopt(struct socket *sock, int level, int optname,
@@ -739,7 +741,7 @@ 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 < CAN_REQUIRED_SIZE(*addr, can_ifindex))
+		if (msg->msg_namelen < RAW_MIN_NAMELEN)
 			return -EINVAL;
 
 		if (addr->can_family != AF_CAN)
@@ -832,8 +834,8 @@ static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	sock_recv_ts_and_drops(msg, sk, skb);
 
 	if (msg->msg_name) {
-		__sockaddr_check_size(sizeof(struct sockaddr_can));
-		msg->msg_namelen = sizeof(struct sockaddr_can);
+		__sockaddr_check_size(RAW_MIN_NAMELEN);
+		msg->msg_namelen = RAW_MIN_NAMELEN;
 		memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
 	}