Subject: Re: [PATCH net-next 2/3] vsock: convert to getsockopt_iter

From: David Laight <[email-masked]>
Date: Fri, 1 May 2026 22:21:05 +0100

On Fri, 1 May 2026 10:32:44 -0700
Bobby Eshleman <[email-masked]> wrote:

> On Fri, May 01, 2026 at 08:52:52AM -0700, Breno Leitao wrote:
> > 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 <[email-masked]>
> > ---
> >  net/vmw_vsock/af_vsock.c | 16 +++++++---------
> >  1 file changed, 7 insertions(+), 9 deletions(-)
> > 
> > diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
> > index 44037b066a5ff..d4a97eeb596e6 100644
> > --- 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 @@ static int vsock_connectible_setsockopt(struct socket *sock,
> >  
> >  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)

I'd wrap that as copy_to_sockopt(&v, len, opt).
or to make the edits easier: copy_to_sockopt(opt, &v, len).
Then if someone decides to change the implementation none of the call
sites need changing.

-- David

> >  		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,
> > 
> > -- 
> > 2.52.0
> >   
> 
> Reviewed-by: Bobby Eshleman <[email-masked]>
>