net: get rid of some pointless casts to sockaddr

The following 4 functions:
  move_addr_to_kernel
  move_addr_to_user
  verify_iovec
  verify_compat_iovec
are always effectively called with a sockaddr_storage.

Make this explicit by changing their signature.

This removes a large number of casts from sockaddr_storage to sockaddr.

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/socket.c b/net/socket.c
index 28a96af..12a48d8 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -181,7 +181,7 @@
  *	invalid addresses -EFAULT is returned. On a success 0 is returned.
  */
 
-int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr *kaddr)
+int move_addr_to_kernel(void __user *uaddr, int ulen, struct sockaddr_storage *kaddr)
 {
 	if (ulen < 0 || ulen > sizeof(struct sockaddr_storage))
 		return -EINVAL;
@@ -209,7 +209,7 @@
  *	specified. Zero is returned for a success.
  */
 
-static int move_addr_to_user(struct sockaddr *kaddr, int klen,
+static int move_addr_to_user(struct sockaddr_storage *kaddr, int klen,
 			     void __user *uaddr, int __user *ulen)
 {
 	int err;
@@ -1449,7 +1449,7 @@
 
 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
 	if (sock) {
-		err = move_addr_to_kernel(umyaddr, addrlen, (struct sockaddr *)&address);
+		err = move_addr_to_kernel(umyaddr, addrlen, &address);
 		if (err >= 0) {
 			err = security_socket_bind(sock,
 						   (struct sockaddr *)&address,
@@ -1556,7 +1556,7 @@
 			err = -ECONNABORTED;
 			goto out_fd;
 		}
-		err = move_addr_to_user((struct sockaddr *)&address,
+		err = move_addr_to_user(&address,
 					len, upeer_sockaddr, upeer_addrlen);
 		if (err < 0)
 			goto out_fd;
@@ -1605,7 +1605,7 @@
 	sock = sockfd_lookup_light(fd, &err, &fput_needed);
 	if (!sock)
 		goto out;
-	err = move_addr_to_kernel(uservaddr, addrlen, (struct sockaddr *)&address);
+	err = move_addr_to_kernel(uservaddr, addrlen, &address);
 	if (err < 0)
 		goto out_put;
 
@@ -1645,7 +1645,7 @@
 	err = sock->ops->getname(sock, (struct sockaddr *)&address, &len, 0);
 	if (err)
 		goto out_put;
-	err = move_addr_to_user((struct sockaddr *)&address, len, usockaddr, usockaddr_len);
+	err = move_addr_to_user(&address, len, usockaddr, usockaddr_len);
 
 out_put:
 	fput_light(sock->file, fput_needed);
@@ -1677,7 +1677,7 @@
 		    sock->ops->getname(sock, (struct sockaddr *)&address, &len,
 				       1);
 		if (!err)
-			err = move_addr_to_user((struct sockaddr *)&address, len, usockaddr,
+			err = move_addr_to_user(&address, len, usockaddr,
 						usockaddr_len);
 		fput_light(sock->file, fput_needed);
 	}
@@ -1716,7 +1716,7 @@
 	msg.msg_controllen = 0;
 	msg.msg_namelen = 0;
 	if (addr) {
-		err = move_addr_to_kernel(addr, addr_len, (struct sockaddr *)&address);
+		err = move_addr_to_kernel(addr, addr_len, &address);
 		if (err < 0)
 			goto out_put;
 		msg.msg_name = (struct sockaddr *)&address;
@@ -1779,7 +1779,7 @@
 	err = sock_recvmsg(sock, &msg, size, flags);
 
 	if (err >= 0 && addr != NULL) {
-		err2 = move_addr_to_user((struct sockaddr *)&address,
+		err2 = move_addr_to_user(&address,
 					 msg.msg_namelen, addr, addr_len);
 		if (err2 < 0)
 			err = err2;
@@ -1933,13 +1933,9 @@
 
 	/* This will also move the address data into kernel space */
 	if (MSG_CMSG_COMPAT & flags) {
-		err = verify_compat_iovec(msg_sys, iov,
-					  (struct sockaddr *)&address,
-					  VERIFY_READ);
+		err = verify_compat_iovec(msg_sys, iov, &address, VERIFY_READ);
 	} else
-		err = verify_iovec(msg_sys, iov,
-				   (struct sockaddr *)&address,
-				   VERIFY_READ);
+		err = verify_iovec(msg_sys, iov, &address, VERIFY_READ);
 	if (err < 0)
 		goto out_freeiov;
 	total_len = err;
@@ -2143,13 +2139,9 @@
 	uaddr = (__force void __user *)msg_sys->msg_name;
 	uaddr_len = COMPAT_NAMELEN(msg);
 	if (MSG_CMSG_COMPAT & flags) {
-		err = verify_compat_iovec(msg_sys, iov,
-					  (struct sockaddr *)&addr,
-					  VERIFY_WRITE);
+		err = verify_compat_iovec(msg_sys, iov, &addr, VERIFY_WRITE);
 	} else
-		err = verify_iovec(msg_sys, iov,
-				   (struct sockaddr *)&addr,
-				   VERIFY_WRITE);
+		err = verify_iovec(msg_sys, iov, &addr, VERIFY_WRITE);
 	if (err < 0)
 		goto out_freeiov;
 	total_len = err;
@@ -2166,7 +2158,7 @@
 	len = err;
 
 	if (uaddr != NULL) {
-		err = move_addr_to_user((struct sockaddr *)&addr,
+		err = move_addr_to_user(&addr,
 					msg_sys->msg_namelen, uaddr,
 					uaddr_len);
 		if (err < 0)