From 342dfc306fb32155314dad277f3c3686b83fb9f1 Mon Sep 17 00:00:00 2001 From: Steffen Hurrle Date: Fri, 17 Jan 2014 22:53:15 +0100 Subject: net: add build-time checks for msg->msg_name size This is a follow-up patch to f3d3342602f8bc ("net: rework recvmsg handler msg_name and msg_namelen logic"). DECLARE_SOCKADDR validates that the structure we use for writing the name information to is not larger than the buffer which is reserved for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR consistently in sendmsg code paths. Signed-off-by: Steffen Hurrle Suggested-by: Hannes Frederic Sowa Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller --- net/packet/af_packet.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'net/packet') diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 12f2f725a945..d711ecbbb9d3 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1584,7 +1584,7 @@ static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t len) { struct sock *sk = sock->sk; - struct sockaddr_pkt *saddr = (struct sockaddr_pkt *)msg->msg_name; + DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name); struct sk_buff *skb = NULL; struct net_device *dev; __be16 proto = 0; @@ -2196,7 +2196,7 @@ static int tpacket_snd(struct packet_sock *po, struct msghdr *msg) __be16 proto; int err, reserve = 0; void *ph; - struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name; + DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name); bool need_wait = !(msg->msg_flags & MSG_DONTWAIT); int tp_len, size_max; unsigned char *addr; @@ -2346,7 +2346,7 @@ static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad, static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) { struct sock *sk = sock->sk; - struct sockaddr_ll *saddr = (struct sockaddr_ll *)msg->msg_name; + DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name); struct sk_buff *skb; struct net_device *dev; __be16 proto; @@ -2922,6 +2922,7 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock, * in, we fill it in now. */ if (sock->type == SOCK_PACKET) { + __sockaddr_check_size(sizeof(struct sockaddr_pkt)); msg->msg_namelen = sizeof(struct sockaddr_pkt); } else { struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll; -- cgit v1.2.3