vsock: convert to getsockopt_iter

Convert AF_VSOCK's getsockopt implementation to use the new
getsockopt_iter callback with sockopt_t. The single
vsock_connectible_getsockopt() callback is shared by both
vsock_stream_ops and vsock_seqpacket_ops, so both proto_ops are
updated to use .getsockopt_iter.

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

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Bobby Eshleman <bobbyeshleman@meta.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20260501-getsock_one-v1-2-810ce23ea70e@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 44037b066a5fff0f1de78aa252044b35d32de0fb..d4a97eeb596e63a89bffcc480bcd3f4ec6a4d802 100644 (file)
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -155,6 +155,7 @@
 #include <linux/random.h>
 #include <linux/skbuff.h>
 #include <linux/smp.h>
+#include <linux/uio.h>
 #include <linux/socket.h>
 #include <linux/stddef.h>
 #include <linux/sysctl.h>
@@ -2091,8 +2092,7 @@ exit:
 
 static int vsock_connectible_getsockopt(struct socket *sock,
                                        int level, int optname,
-                                       char __user *optval,
-                                       int __user *optlen)
+                                       sockopt_t *opt)
 {
        struct sock *sk = sock->sk;
        struct vsock_sock *vsk = vsock_sk(sk);
@@ -2110,8 +2110,7 @@ static int vsock_connectible_getsockopt(struct socket *sock,
        if (level != AF_VSOCK)
                return -ENOPROTOOPT;
 
-       if (get_user(len, optlen))
-               return -EFAULT;
+       len = opt->optlen;
 
        memset(&v, 0, sizeof(v));
 
@@ -2142,11 +2141,10 @@ static int vsock_connectible_getsockopt(struct socket *sock,
                return -EINVAL;
        if (len > lv)
                len = lv;
-       if (copy_to_user(optval, &v, len))
+       if (copy_to_iter(&v, len, &opt->iter_out) != len)
                return -EFAULT;
 
-       if (put_user(len, optlen))
-               return -EFAULT;
+       opt->optlen = len;
 
        return 0;
 }
@@ -2631,7 +2629,7 @@ static const struct proto_ops vsock_stream_ops = {
        .listen = vsock_listen,
        .shutdown = vsock_shutdown,
        .setsockopt = vsock_connectible_setsockopt,
-       .getsockopt = vsock_connectible_getsockopt,
+       .getsockopt_iter = vsock_connectible_getsockopt,
        .sendmsg = vsock_connectible_sendmsg,
        .recvmsg = vsock_connectible_recvmsg,
        .mmap = sock_no_mmap,
@@ -2653,7 +2651,7 @@ static const struct proto_ops vsock_seqpacket_ops = {
        .listen = vsock_listen,
        .shutdown = vsock_shutdown,
        .setsockopt = vsock_connectible_setsockopt,
-       .getsockopt = vsock_connectible_getsockopt,
+       .getsockopt_iter = vsock_connectible_getsockopt,
        .sendmsg = vsock_connectible_sendmsg,
        .recvmsg = vsock_connectible_recvmsg,
        .mmap = sock_no_mmap,