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 <steffen@hurrle.net>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
index dd4d506..2954dcb 100644
--- a/net/decnet/af_decnet.c
+++ b/net/decnet/af_decnet.c
@@ -1808,6 +1808,7 @@
rv = (flags & MSG_PEEK) ? -sk->sk_err : sock_error(sk);
if ((rv >= 0) && msg->msg_name) {
+ __sockaddr_check_size(sizeof(struct sockaddr_dn));
memcpy(msg->msg_name, &scp->peer, sizeof(struct sockaddr_dn));
msg->msg_namelen = sizeof(struct sockaddr_dn);
}
@@ -1914,7 +1915,7 @@
int err = 0;
size_t sent = 0;
int addr_len = msg->msg_namelen;
- struct sockaddr_dn *addr = (struct sockaddr_dn *)msg->msg_name;
+ DECLARE_SOCKADDR(struct sockaddr_dn *, addr, msg->msg_name);
struct sk_buff *skb = NULL;
struct dn_skb_cb *cb;
size_t len;