Convert TIPC sockets (msg, packet, stream proto_ops) to use the new
getsockopt_iter callback with sockopt_t.

Key changes:
- Replace (char __user *optval, int __user *optlen) with sockopt_t *sopt
- Use sopt->optlen for buffer length (input) and returned size (output)
- Use copy_to_iter() instead of put_user()/copy_to_user()

The sockopt_t parameter is named sopt to avoid collision with the
existing optname parameter named opt.

Note: Dropped the unnecessary parentheses to make checkpatch happier.
Also dropped two now-stale comments that referred to the old "res"
variable handling.

Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Signed-off-by: Breno Leitao <leitao@debian.org>
---
 net/tipc/socket.c | 33 +++++++++++++++++----------------
 1 file changed, 17 insertions(+), 16 deletions(-)

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 9329919fb07f0..3a94278a44ac4 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -37,6 +37,7 @@
 
 #include <linux/rhashtable.h>
 #include <linux/sched/signal.h>
+#include <linux/uio.h>
 #include <trace/events/sock.h>
 
 #include "core.h"
@@ -3220,8 +3221,7 @@ static int tipc_setsockopt(struct socket *sock, int lvl, int opt,
  * @sock: socket structure
  * @lvl: option level
  * @opt: option identifier
- * @ov: receptacle for option value
- * @ol: receptacle for length of option value
+ * @sopt: socket option container (input buffer length, output value/length)
  *
  * For stream sockets only, returns 0 length result for all IPPROTO_TCP options
  * (to ease compatibility).
@@ -3229,22 +3229,22 @@ static int tipc_setsockopt(struct socket *sock, int lvl, int opt,
  * Return: 0 on success, errno otherwise
  */
 static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
-			   char __user *ov, int __user *ol)
+			   sockopt_t *sopt)
 {
 	struct sock *sk = sock->sk;
 	struct tipc_sock *tsk = tipc_sk(sk);
 	struct tipc_service_range seq;
 	int len, scope;
+	int res = 0;
 	u32 value;
-	int res;
 
-	if ((lvl == IPPROTO_TCP) && (sock->type == SOCK_STREAM))
-		return put_user(0, ol);
+	if (lvl == IPPROTO_TCP && sock->type == SOCK_STREAM) {
+		sopt->optlen = 0;
+		return 0;
+	}
 	if (lvl != SOL_TIPC)
 		return -ENOPROTOOPT;
-	res = get_user(len, ol);
-	if (res)
-		return res;
+	len = sopt->optlen;
 
 	lock_sock(sk);
 
@@ -3260,7 +3260,6 @@ static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
 		break;
 	case TIPC_CONN_TIMEOUT:
 		value = tsk->conn_timeout;
-		/* no need to set "res", since already 0 at this point */
 		break;
 	case TIPC_NODE_RECVQ_DEPTH:
 		value = 0; /* was tipc_queue_size, now obsolete */
@@ -3284,15 +3283,17 @@ static int tipc_getsockopt(struct socket *sock, int lvl, int opt,
 	release_sock(sk);
 
 	if (res)
-		return res;	/* "get" failed */
+		return res;
 
 	if (len < sizeof(value))
 		return -EINVAL;
 
-	if (copy_to_user(ov, &value, sizeof(value)))
+	if (copy_to_iter(&value, sizeof(value), &sopt->iter_out) !=
+	    sizeof(value))
 		return -EFAULT;
+	sopt->optlen = sizeof(value);
 
-	return put_user(sizeof(value), ol);
+	return 0;
 }
 
 static int tipc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
@@ -3365,7 +3366,7 @@ static const struct proto_ops msg_ops = {
 	.listen		= sock_no_listen,
 	.shutdown	= tipc_shutdown,
 	.setsockopt	= tipc_setsockopt,
-	.getsockopt	= tipc_getsockopt,
+	.getsockopt_iter = tipc_getsockopt,
 	.sendmsg	= tipc_sendmsg,
 	.recvmsg	= tipc_recvmsg,
 	.mmap		= sock_no_mmap,
@@ -3385,7 +3386,7 @@ static const struct proto_ops packet_ops = {
 	.listen		= tipc_listen,
 	.shutdown	= tipc_shutdown,
 	.setsockopt	= tipc_setsockopt,
-	.getsockopt	= tipc_getsockopt,
+	.getsockopt_iter = tipc_getsockopt,
 	.sendmsg	= tipc_send_packet,
 	.recvmsg	= tipc_recvmsg,
 	.mmap		= sock_no_mmap,
@@ -3405,7 +3406,7 @@ static const struct proto_ops stream_ops = {
 	.listen		= tipc_listen,
 	.shutdown	= tipc_shutdown,
 	.setsockopt	= tipc_setsockopt,
-	.getsockopt	= tipc_getsockopt,
+	.getsockopt_iter = tipc_getsockopt,
 	.sendmsg	= tipc_sendstream,
 	.recvmsg	= tipc_recvstream,
 	.mmap		= sock_no_mmap,

-- 
2.53.0-Meta