From 9e9714742fb70467464359693a73b911a630226f Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Thu, 25 Mar 2021 13:58:48 +0100 Subject: can: bcm/raw: fix msg_namelen values depending on CAN_REQUIRED_SIZE 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: f5223e9eee65 ("can: extend sockaddr_can to include j1939 members") Reported-by: Richard Weinberger Tested-by: Richard Weinberger Acked-by: Kurt Van Dijck Link: https://lore.kernel.org/linux-can/1135648123.112255.1616613706554.JavaMail.zimbra@nod.at/T/#t Link: https://lore.kernel.org/r/20210325125850.1620-1-socketcan@hartkopp.net Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- net/can/bcm.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'net/can/bcm.c') 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 "); 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); } -- cgit v1.2.3