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>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
index 15d23b8c2129..cd71f3a540be 100644
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -103,7 +103,7 @@ int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
                 return err;
 
         if (msg->msg_name) {
-                struct sockaddr_in6 *u = (struct sockaddr_in6 *) msg->msg_name;
+                DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
                 if (msg->msg_namelen < sizeof(struct sockaddr_in6) ||
                     u->sin6_family != AF_INET6) {
                         return -EINVAL;